1
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Shen Y, Li T, Sun C, Cheng X, Chen Z, Wang G, Yang X. Atg7 autophagy-independent role on governing neural stem cell fate could be potentially applied for regenerative medicine. Cell Death Differ 2024; 31:1375-1388. [PMID: 38898232 PMCID: PMC11445561 DOI: 10.1038/s41418-024-01330-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 06/11/2024] [Accepted: 06/12/2024] [Indexed: 06/21/2024] Open
Abstract
A literature review showed that Atg7 biological role was associated with the development and pathogenesis of nervous system, but very few reports focused on Atg7 role on neurogenesis at the region of spinal cord, so that we are committed to explore the subject. Atg7 expression in neural tube is incrementally increased during neurogenesis. Atg7 neural-specific knockout mice demonstrated the impaired motor function and imbalance of neuronal and glial cell differentiation during neurogenesis, which was similarly confirmed in primary neurosphere culture and reversely verified by Atg7 overexpression in unilateral neural tubes of gastrula chicken embryos. Furthermore, activating autophagy in neural stem cells (NSCs) of neurospheres did not rescue Atg7 deficiency-suppressed neuronal differentiation, but Atg7 overexpression on the basis of autophagy inhibition could reverse Atg7 deficiency-suppressed neuronal differentiation, which provides evidence for the existence of Atg7 role of autophagy-independent function. The underlying mechanism is that Atg7 deficiency directly caused the alteration of cell cycle length of NSCs, which is controlled by Atg7 through specifically binding Mdm2, thereby affecting neuronal differentiation during neurogenesis. Eventually, the effect of overexpressing Atg7-promoting neuronal differentiation was proved in spinal cord injury model as well. Taken together, this study revealed that Atg7 was involved in regulating neurogenesis by a non-autophagic signaling process, and this finding also shed light on the potential application in regenerative medicine.
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Affiliation(s)
- Yao Shen
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China
| | - Tingting Li
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China
| | - Chengyang Sun
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China
| | - Xin Cheng
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China
| | - Zhi Chen
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China
| | - Guang Wang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China.
- Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou, 510632, China.
- Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Guangdong Second Provincial General Hospital, School of Medicine, Jinan University, Guangzhou, 510220, China.
| | - Xuesong Yang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, School of Medicine, Jinan University, Guangzhou, 510632, China.
- Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou, 510632, China.
- Clinical Research Center, Clifford Hospital, Guangzhou, 511496, China.
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2
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Tabata K, Imai K, Fukuda K, Yamamoto K, Kunugi H, Fujita T, Kaminishi T, Tischer C, Neumann B, Reither S, Verissimo F, Pepperkok R, Yoshimori T, Hamasaki M. Palmitoylation of ULK1 by ZDHHC13 plays a crucial role in autophagy. Nat Commun 2024; 15:7194. [PMID: 39169022 PMCID: PMC11339336 DOI: 10.1038/s41467-024-51402-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 08/05/2024] [Indexed: 08/23/2024] Open
Abstract
Autophagy is a highly conserved process from yeast to mammals in which intracellular materials are engulfed by a double-membrane organelle called autophagosome and degrading materials by fusing with the lysosome. The process of autophagy is regulated by sequential recruitment and function of autophagy-related (Atg) proteins. Genetic hierarchical analyses show that the ULK1 complex comprised of ULK1-FIP200-ATG13-ATG101 translocating from the cytosol to autophagosome formation sites as a most upstream ATG factor; this translocation is critical in autophagy initiation. However, how this translocation occurs remains unclear. Here, we show that ULK1 is palmitoylated by palmitoyltransferase ZDHHC13 and translocated to the autophagosome formation site upon autophagy induction. We find that the ULK1 palmitoylation is required for autophagy initiation. Moreover, the ULK1 palmitoylated enhances the phosphorylation of ATG14L, which is required for activating PI3-Kinase and producing phosphatidylinositol 3-phosphate, one of the autophagosome membrane's lipids. Our results reveal how the most upstream ULK1 complex translocates to the autophagosome formation sites during autophagy.
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Affiliation(s)
- Keisuke Tabata
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Kenta Imai
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Koki Fukuda
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Kentaro Yamamoto
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hayato Kunugi
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Toshiharu Fujita
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Tatsuya Kaminishi
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
- Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, Osaka, Japan
| | | | - Beate Neumann
- Advanced Light Microscopy Facility, EMBL, Heidelberg, Germany
| | - Sabine Reither
- Advanced Light Microscopy Facility, EMBL, Heidelberg, Germany
| | | | - Rainer Pepperkok
- Advanced Light Microscopy Facility, EMBL, Heidelberg, Germany
- Cell Biology and Biophysics Unit, EMBL, Heidelberg, Germany
| | - Tamotsu Yoshimori
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan.
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.
- Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, Osaka, Japan.
| | - Maho Hamasaki
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan.
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.
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3
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Pareek G, Kundu M. Physiological functions of ULK1/2. J Mol Biol 2024; 436:168472. [PMID: 38311233 PMCID: PMC11382334 DOI: 10.1016/j.jmb.2024.168472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/10/2024]
Abstract
UNC-51-like kinases 1 and 2 (ULK1/2) are serine/threonine kinases that are best known for their evolutionarily conserved role in the autophagy pathway. Upon sensing the nutrient status of a cell, ULK1/2 integrate signals from upstream cellular energy sensors such as mTOR and AMPK and relay them to the downstream components of the autophagy machinery. ULK1/2 also play indispensable roles in the selective autophagy pathway, removing damaged mitochondria, invading pathogens, and toxic protein aggregates. Additional functions of ULK1/2 have emerged beyond autophagy, including roles in protein trafficking, RNP granule dynamics, and signaling events impacting innate immunity, axon guidance, cellular homeostasis, and cell fate. Therefore, it is no surprise that alterations in ULK1/2 expression and activity have been linked with pathophysiological processes, including cancer, neurological disorders, and cardiovascular diseases. Growing evidence suggests that ULK1/2 function as biological rheostats, tuning cellular functions to intra and extra-cellular cues. Given their broad physiological relevance, ULK1/2 are candidate targets for small molecule activators or inhibitors that may pave the way for the development of therapeutics for the treatment of diseases in humans.
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Affiliation(s)
- Gautam Pareek
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Mondira Kundu
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, TN, USA.
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4
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Wang Y, Xu T, Wang H, Xia G, Huang X. Inhibition of autophagy induced by tetrandrine promotes the accumulation of reactive oxygen species and sensitizes efficacy of tetrandrine in pancreatic cancer. Cancer Cell Int 2024; 24:241. [PMID: 38987818 PMCID: PMC11238362 DOI: 10.1186/s12935-024-03410-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 06/19/2024] [Indexed: 07/12/2024] Open
Abstract
Pancreatic cancer, characterized by its poor prognosis, exhibits a marked resistance to conventional chemotherapy and immunotherapy, underscoring the urgent need for more effective treatment modalities. In light of this, the present study is designed to assess the potential antineoplastic efficacy of a combined regimen involving tetrandrine, a plant-derived alkaloid, and autophagy inhibitors in the context of pancreatic cancer. Electron microscopy and immunoblots showed that tetrandrine promoted the formation of autophagosomes and the upregulation of LC3II and the downregulation of p62 expression, indicating that tetrandrine induced autophagy in pancreatic cancer cells. Western blot revealed that tetrandrine inhibited the phosphorylation of AKT and mTOR, as well as the expression of Bcl-2, while upregulating Beclin-1 expression. Moreover, tetrandrine promoted the transcription and protein expression of ATG7. Following the combination of autophagy inhibitors and tetrandrine, the apoptotic rate and cell death significantly increased in pancreatic cancer cells. Consistent results were obtained when ATG7 was silenced. Additionally, tetrandrine induced the generation of ROS, which was involved in the activation of autophagy and apoptosis. Further investigation revealed that upon autophagy inhibition, ROS accumulated in pancreatic cancer cells, resulting in decreased mitochondrial membrane potential and further induction of apoptosis. The results of treating subcutaneous xenograft tumors with a combination of tetrandrine and chloroquine validated that autophagy inhibition enhances the toxicity of tetrandrine against pancreatic cancer in vivo. Altogether, our study demonstrates that tetrandrine induces cytoprotective autophagy in pancreatic cancer cells. Inhibiting tetrandrine-induced autophagy promotes the accumulation of ROS and enhances its toxicity against pancreatic cancer.
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Affiliation(s)
- Yiwei Wang
- Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Rd, Shanghai, 200233, China
| | - Ting Xu
- Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Rd, Shanghai, 200233, China
| | - Hongcheng Wang
- Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Rd, Shanghai, 200233, China
| | - Guanggai Xia
- Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Rd, Shanghai, 200233, China.
| | - Xinyu Huang
- Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Rd, Shanghai, 200233, China.
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5
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Wang B, Pareek G, Kundu M. ULK/Atg1: phasing in and out of autophagy. Trends Biochem Sci 2024; 49:494-505. [PMID: 38565496 PMCID: PMC11162330 DOI: 10.1016/j.tibs.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/28/2024] [Accepted: 03/08/2024] [Indexed: 04/04/2024]
Abstract
Autophagy - a highly regulated intracellular degradation process - is pivotal in maintaining cellular homeostasis. Liquid-liquid phase separation (LLPS) is a fundamental mechanism regulating the formation and function of membrane-less compartments. Recent research has unveiled connections between LLPS and autophagy, suggesting that phase separation events may orchestrate the spatiotemporal organization of autophagic machinery and cargo sequestration. The Unc-51-like kinase (ULK)/autophagy-related 1 (Atg1) family of proteins is best known for its regulatory role in initiating autophagy, but there is growing evidence that the functional spectrum of ULK/Atg1 extends beyond autophagy regulation. In this review, we explore the spatial and temporal regulation of the ULK/Atg1 family of kinases, focusing on their recruitment to LLPS-driven compartments, and highlighting their multifaceted functions beyond their traditional role.
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Affiliation(s)
- Bo Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China; Shenzhen Research Institute of Xiamen University, Shenzhen, 518057, China
| | - Gautam Pareek
- Department of Cell and Molecular Biology, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Mondira Kundu
- Department of Cell and Molecular Biology, St Jude Children's Research Hospital, Memphis, TN 38105, USA.
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6
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Shang JN, Yu CG, Li R, Xi Y, Jian YJ, Xu N, Chen S. The nonautophagic functions of autophagy-related proteins. Autophagy 2024; 20:720-734. [PMID: 37682088 PMCID: PMC11062363 DOI: 10.1080/15548627.2023.2254664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 08/30/2023] [Indexed: 09/09/2023] Open
Abstract
ABBREVIATIONS ATG: autophagy related; BECN1: beclin 1; cAMP: cyclic adenosine monophosphate; dsDNA: double-stranded DNA; EMT: epithelial-mesenchymal transition; IFN: interferon; ISCs: intestinal stem cells; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAPK/JNK: mitogen-activated protein kinase/c-Jun N-terminal kinases; MTOR: mechanistic target of rapamycin kinase; STING1: stimulator of interferon response cGAMP interactor 1; UVRAG: UV radiation resistance associated; VPS: vacuolar protein sorting.
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Affiliation(s)
- Jia-Ni Shang
- Laboratory of Molecular and Cellular Biology, Institute of Metabolism and Health, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan, PR China
| | - Chen-Ge Yu
- Laboratory of Molecular and Cellular Biology, Institute of Metabolism and Health, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan, PR China
| | - Rui Li
- Laboratory of Molecular and Cellular Biology, Institute of Metabolism and Health, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan, PR China
| | - Yan Xi
- Laboratory of Molecular and Cellular Biology, Institute of Metabolism and Health, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan, PR China
| | - Yue Jenny Jian
- Nanjing Foreign Language School, Nanjing, Jiangsu, PR China
| | - Nan Xu
- Laboratory of Molecular and Cellular Biology, Institute of Metabolism and Health, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan, PR China
| | - Su Chen
- Laboratory of Molecular and Cellular Biology, Institute of Metabolism and Health, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan, PR China
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7
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Vaughan RM, Dickson BM, Martin KR, MacKeigan JP. Molecular dynamics simulations provide insights into ULK-101 potency and selectivity toward autophagic kinases ULK1/2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.01.569261. [PMID: 38077086 PMCID: PMC10705459 DOI: 10.1101/2023.12.01.569261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Kinase domains are highly conserved within protein kinases in both sequence and structure. Many factors, including phosphorylation, amino acid substitutions or mutations, and small molecule inhibitor binding, influence conformations of the kinase domain and enzymatic activity. The serine/threonine kinases ULK1 and ULK2 are highly conserved with N- and C-terminal domains, phosphate-binding P-loops, αC-helix, regulatory and catalytic spines, and activation loop DFG and APE motifs. Here, we performed molecular dynamics (MD) simulations to understand better the potency and selectivity of the ULK1/2 small molecule inhibitor, ULK-101. We observed stable bound states for ULK-101 to the adenosine triphosphate (ATP)-binding site of ULK2, coordinated by hydrogen bonding with the hinge backbone and the catalytic lysine sidechain. Notably, ULK-101 occupies a hydrophobic pocket associated with the N-terminus of the αC-helix. Large movements in the P-loop are also associated with ULK-101 inhibitor binding and exit from ULK2. Our data further suggests that ULK-101 could induce a folded P-loop conformation and hydrophobic pocket reflected in its nanomolar potency and kinome selectivity.
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Affiliation(s)
- Robert M. Vaughan
- Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Bradley M. Dickson
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Katie R. Martin
- Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Jeffrey P. MacKeigan
- Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
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8
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Liang P, Zhang J, Wu Y, Zheng S, Xu Z, Yang S, Wang J, Ma S, Xiao L, Hu T, Jiang W, Huang C, Xing Q, Kundu M, Wang B. An ULK1/2-PXN mechanotransduction pathway suppresses breast cancer cell migration. EMBO Rep 2023; 24:e56850. [PMID: 37846507 PMCID: PMC10626438 DOI: 10.15252/embr.202356850] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 09/09/2023] [Accepted: 09/27/2023] [Indexed: 10/18/2023] Open
Abstract
The remodeling and stiffening of the extracellular matrix (ECM) is a well-recognized modulator of breast cancer progression. How changes in the mechanical properties of the ECM are converted into biochemical signals that direct tumor cell migration and metastasis remain poorly characterized. Here, we describe a new role for the autophagy-inducing serine/threonine kinases ULK1 and ULK2 in mechanotransduction. We show that ULK1/2 activity inhibits the assembly of actin stress fibers and focal adhesions (FAs) and as a consequence impedes cell contraction and migration, independent of its role in autophagy. Mechanistically, we identify PXN/paxillin, a key component of the mechanotransducing machinery, as a direct binding partner and substrate of ULK1/2. ULK-mediated phosphorylation of PXN at S32 and S119 weakens homotypic interactions and liquid-liquid phase separation of PXN, impairing FA assembly, which in turn alters the mechanical properties of breast cancer cells and their response to mechanical stimuli. ULK1/2 and the well-characterized PXN regulator, FAK/Src, have opposing functions on mechanotransduction and compete for phosphorylation of adjacent serine and tyrosine residues. Taken together, our study reveals ULK1/2 as important regulator of PXN-dependent mechanotransduction.
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Affiliation(s)
- Peigang Liang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Jiaqi Zhang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Yuchen Wu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Shanyuan Zheng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Zhaopeng Xu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Shuo Yang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Jinfang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Suibin Ma
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
| | - Li Xiao
- Department of OncologyZhongshan Hospital of Xiamen UniversityXiamenChina
| | - Tianhui Hu
- Cancer Research Center, School of MedicineXiamen UniversityXiamenChina
| | - Wenxue Jiang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life SciencesHubei UniversityWuhanChina
| | - Chaoqun Huang
- Central LaboratoryThe Fifth Hospital of XiamenXiamenChina
| | - Qiong Xing
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life SciencesHubei UniversityWuhanChina
| | - Mondira Kundu
- Department of Cell and Molecular BiologySt. Jude Children's Research HospitalMemphisTNUSA
| | - Bo Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life SciencesXiamen UniversityXiamenChina
- Shenzhen Research Institute of Xiamen UniversityShenzhenChina
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9
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Taraborrelli L, Şenbabaoğlu Y, Wang L, Lim J, Blake K, Kljavin N, Gierke S, Scherl A, Ziai J, McNamara E, Owyong M, Rao S, Calviello AK, Oreper D, Jhunjhunwala S, Argiles G, Bendell J, Kim TW, Ciardiello F, Wongchenko MJ, de Sauvage FJ, de Sousa E Melo F, Yan Y, West NR, Murthy A. Tumor-intrinsic expression of the autophagy gene Atg16l1 suppresses anti-tumor immunity in colorectal cancer. Nat Commun 2023; 14:5945. [PMID: 37741832 PMCID: PMC10517947 DOI: 10.1038/s41467-023-41618-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 09/12/2023] [Indexed: 09/25/2023] Open
Abstract
Microsatellite-stable colorectal cancer (MSS-CRC) is highly refractory to immunotherapy. Understanding tumor-intrinsic determinants of immunotherapy resistance is critical to improve MSS-CRC patient outcomes. Here, we demonstrate that high tumor expression of the core autophagy gene ATG16L1 is associated with poor clinical response to anti-PD-L1 therapy in KRAS-mutant tumors from IMblaze370 (NCT02788279), a large phase III clinical trial of atezolizumab (anti-PD-L1) in advanced metastatic MSS-CRC. Deletion of Atg16l1 in engineered murine colon cancer organoids inhibits tumor growth in primary (colon) and metastatic (liver and lung) niches in syngeneic female hosts, primarily due to increased sensitivity to IFN-γ-mediated immune pressure. ATG16L1 deficiency enhances programmed cell death of colon cancer organoids induced by IFN-γ and TNF, thus increasing their sensitivity to host immunity. In parallel, ATG16L1 deficiency reduces tumor stem-like populations in vivo independently of adaptive immune pressure. This work reveals autophagy as a clinically relevant mechanism of immune evasion and tumor fitness in MSS-CRC and provides a rationale for autophagy inhibition to boost immunotherapy responses in the clinic.
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Affiliation(s)
- Lucia Taraborrelli
- Department of Cancer Immunology, Genentech Inc., South San Francisco, USA
| | - Yasin Şenbabaoğlu
- Department of Oncology Bioinformatics, Genentech Inc., South San Francisco, USA
| | - Lifen Wang
- Department of Cancer Immunology, Genentech Inc., South San Francisco, USA
| | - Junghyun Lim
- Department of Cancer Immunology, Genentech Inc., South San Francisco, USA
| | - Kerrigan Blake
- Department of Cancer Immunology, Genentech Inc., South San Francisco, USA
| | - Noelyn Kljavin
- Department of Molecular Oncology, Genentech Inc., South San Francisco, USA
| | - Sarah Gierke
- Center for Advanced Light Microscopy, Genentech Inc., South San Francisco, USA
- Department of Pathology, Genentech Inc., South San Francisco, USA
| | - Alexis Scherl
- Department of Pathology, Genentech Inc., South San Francisco, USA
| | - James Ziai
- Department of Pathology, Genentech Inc., South San Francisco, USA
| | - Erin McNamara
- Department of In Vivo Pharmacology, Genentech Inc., South San Francisco, USA
| | - Mark Owyong
- Department of In Vivo Pharmacology, Genentech Inc., South San Francisco, USA
| | - Shilpa Rao
- Department of Oncology Bioinformatics, Genentech Inc., South San Francisco, USA
| | | | - Daniel Oreper
- Department of Oncology Bioinformatics, Genentech Inc., South San Francisco, USA
| | - Suchit Jhunjhunwala
- Department of Oncology Bioinformatics, Genentech Inc., South San Francisco, USA
| | - Guillem Argiles
- Vall d'Hebrón Institute of Oncology, Vall d'Hebrón University Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Johanna Bendell
- Sarah Cannon Research Institute/Tennessee Oncology, Nashville, TN, USA
| | - Tae Won Kim
- Department of Oncology, Medical Center, University of Ulsan, Seoul, Korea
| | - Fortunato Ciardiello
- Department of Precision Medicine, Università degli Studi della Campania Luigi Vanvitelli, Naples, Italy
| | | | | | | | - Yibing Yan
- Oncology Biomarker Development, Genentech, Inc., South San Francisco, CA, USA
| | - Nathaniel R West
- Department of Cancer Immunology, Genentech Inc., South San Francisco, USA.
| | - Aditya Murthy
- Department of Cancer Immunology, Genentech Inc., South San Francisco, USA.
- Gilead Sciences, Foster City, USA.
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10
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Ma C, Xu Q, Huang S, Song J, Sun M, Zhang J, Chu G, Zhang B, Bai Y, Zhao X, Wang Z, Li P. The HIF-1α/miR-26a-5p/PFKFB3/ULK1/2 axis regulates vascular remodeling in hypoxia-induced pulmonary hypertension by modulation of autophagy. FASEB J 2023; 37:e22906. [PMID: 37052859 DOI: 10.1096/fj.202200699rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 01/29/2023] [Accepted: 03/23/2023] [Indexed: 04/14/2023]
Abstract
Pulmonary arterial hypertension (PAH) is a progressive and life-threatening disease characterized by pulmonary vascular remodeling, which may cause right heart failure and even death. Accumulated evidence confirmed that microRNA-26 family play critical roles in cardiovascular disease; however, their function in PAH remains largely unknown. Here, we investigated the expression of miR-26 family in plasma from PAH patients using quantitative RT-PCR, and identified miR-26a-5p as the most downregulated member, which was also decreased in hypoxia-induced pulmonary arterial smooth muscle cell (PASMC) autophagy models and lung tissues of PAH patients. Furthermore, chromatin immunoprecipitation (ChIP) analysis and luciferase reporter assays revealed that hypoxia-inducible factor 1α (HIF-1α) specifically interacted with the promoter of miR-26a-5p and inhibited its expression in PASMCs. Tandem mRFP-GFP-LC3B fluorescence microscopy demonstrated that miR-26a-5p inhibited hypoxia-induced PAMSC autophagy, characterized by reduced formation of autophagosomes and autolysosomes. In addition, results showed that miR-26a-5p overexpression potently inhibited PASMC proliferation and migration, as determined by cell counting kit-8, EdU staining, wound-healing, and transwell assays. Mechanistically, PFKFB3, ULK1, and ULK2 were direct targets of miR-26a-5p, as determined by dual-luciferase reporter gene assays and western blots. Meanwhile, PFKFB3 could further enhance the phosphorylation level of ULK1 and promote autophagy in PASMCs. Moreover, intratracheal administration of adeno-miR-26a-5p markedly alleviated right ventricular hypertrophy and pulmonary vascular remodeling in hypoxia-induced PAH rat models in vivo. Taken together, the HIF-1α/miR-26a-5p/PFKFB3/ULK1/2 axis plays critical roles in the regulation of hypoxia-induced PASMC autophagy and proliferation. MiR-26a-5p may represent as an attractive biomarker for the diagnosis and treatment of PAH.
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Affiliation(s)
- Chaoqun Ma
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
- Cardiovascular Research Institute and Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, Liaoning, China
| | - Qiang Xu
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
- Department of Cardiology, Navy 905 Hospital, Naval Medical University, Shanghai, China
| | - Songqun Huang
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Jingwen Song
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Minglei Sun
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Jingyu Zhang
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Guojun Chu
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Bili Zhang
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Yuan Bai
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Xianxian Zhao
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Zhongkai Wang
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Pan Li
- Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, China
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11
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Wang J, Meng X, Chen K, Feng J. An autophagy-related four-lncRNA signature helps to predict progression-free survival of neuroblastoma patients. Front Oncol 2022; 12:1014845. [PMID: 36530992 PMCID: PMC9753905 DOI: 10.3389/fonc.2022.1014845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 11/14/2022] [Indexed: 09/14/2023] Open
Abstract
BACKGROUND This study aimed to identify autophagy-related long non-coding RNAs (lncRNAs) associated with progression of neuroblastoma (NB), and to build an autophagy-related lncRNA signature that helps to predict progression-free survival (PFS) of NB. METHODS Three independent gene expression datasets were utilized in this study. Autophagy-related genes (ARG) associated with PFS of NB patients were firstly identified by univariate Cox survival analysis. lncRNAs correlated with those PFS-related ARGs were then identified. The least absolute shrinkage and selection operator (LASSO) regression and multivariate Cox regression analyses were performed to select out those lncRNAs with the best prognostic value for PFS. The Receiver Operating Characteristic (ROC) and Area Under Curve (AUC) analyses were performed to assess the prediction accuracy. RESULTS Four autophagy-related lncRNAs (AL356599.1, AC022075.1, AC020928.1 and LINC02076) were found to be with the best prognostic value and integrated into a four-lncRNA risk signature for predicting PFS of NB patients. The four-lncRNA signature significantly stratify NB patients into two risk groups, with high-risk group has significantly poorer PFS than the low-risk group. The prognostic role of the lncRNA signature was independent with other clinical risk factors. The ROC curves revealed that the lncRNA signature has a good performance in predicting PFS (AUC > 0.70). A nomogram based on COG (Children's Oncology Group) risk and the lncRNA risk score was constructed, showing good prediction accuracy (C-index = 0.700). The prognostic ability of the nomogram was better than that of COG risk alone (AUC = 0.790 versus AUC = 0.748). GSEA analyses revealed that multiple autophagy-related gene sets are significantly enriched in the low-risk group. CONCLUSIONS We identified an autophagy-related four-lncRNA signature that could help to predict the PFS of NB patients. Autophagy-related gene sets are significantly enriched in low-risk group, suggesting tumor suppressive roles of autophagy in NB.
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Affiliation(s)
| | | | | | - Jiexiong Feng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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12
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Autophagy protein ULK1 interacts with and regulates SARM1 during axonal injury. Proc Natl Acad Sci U S A 2022; 119:e2203824119. [PMID: 36375051 PMCID: PMC9704737 DOI: 10.1073/pnas.2203824119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Autophagy is a cellular catabolic pathway generally thought to be neuroprotective. However, autophagy and in particular its upstream regulator, the ULK1 kinase, can also promote axonal degeneration. We examined the role and the mechanisms of autophagy in axonal degeneration using a mouse model of contusive spinal cord injury (SCI). Consistent with activation of autophagy during axonal degeneration following SCI, autophagosome marker LC3, ULK1 kinase, and ULK1 target, phospho-ATG13, accumulated in the axonal bulbs and injured axons. SARM1, a TIR NADase with a pivotal role in axonal degeneration, colocalized with ULK1 within 1 h after SCI, suggesting possible interaction between autophagy and SARM1-mediated axonal degeneration. In our in vitro experiments, inhibition of autophagy, including Ulk1 knockdown and ULK1 inhibitor, attenuated neurite fragmentation and reduced accumulation of SARM1 puncta in neurites of primary cortical neurons subjected to glutamate excitotoxicity. Immunoprecipitation data demonstrated that ULK1 physically interacted with SARM1 in vitro and in vivo and that SAM domains of SARM1 were necessary for ULK1-SARM1 complex formation. Consistent with a role in regulation of axonal degeneration, in primary cortical neurons ULK1-SARM1 interaction increased upon neurite damage. Supporting a role for autophagy and ULK1 in regulation of SARM1 in axonal degeneration in vivo, axonal ULK1 activation and accumulation of SARM1 were both decreased after SCI in Becn1+/- autophagy hypomorph mice compared to wild-type (WT) controls. These findings suggest a regulatory crosstalk between autophagy and axonal degeneration pathways, which is mediated through ULK1-SARM1 interaction and contributes to the ability of SARM1 to accumulate in injured axons.
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13
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Nrf2 Pathway and Autophagy Crosstalk: New Insights into Therapeutic Strategies for Ischemic Cerebral Vascular Diseases. Antioxidants (Basel) 2022; 11:antiox11091747. [PMID: 36139821 PMCID: PMC9495910 DOI: 10.3390/antiox11091747] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/27/2022] [Accepted: 08/30/2022] [Indexed: 11/17/2022] Open
Abstract
Cerebrovascular disease is highly prevalent and has a complex etiology and variable pathophysiological activities. It thus poses a serious threat to human life and health. Currently, pathophysiological research on cerebrovascular diseases is gradually improving, and oxidative stress and autophagy have been identified as important pathophysiological activities that are gradually attracting increasing attention. Many studies have found some effects of oxidative stress and autophagy on cerebrovascular diseases, and studies on the crosstalk between the two in cerebrovascular diseases have made modest progress. However, further, more detailed studies are needed to determine the specific mechanisms. This review discusses nuclear factor erythroid 2-related factor 2 (Nrf2) molecules, which are closely associated with oxidative stress and autophagy, and the crosstalk between them, with the aim of providing clues for studying the two important pathophysiological changes and their crosstalk in cerebrovascular diseases as well as exploring new target treatments.
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14
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Function and regulation of ULK1: From physiology to pathology. Gene 2022; 840:146772. [PMID: 35905845 DOI: 10.1016/j.gene.2022.146772] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/03/2022] [Accepted: 07/24/2022] [Indexed: 11/21/2022]
Abstract
The expression of ULK1, a core protein of autophagy, is closely related to autophagic activity. Numerous studies have shown that pathological abnormal expression of ULK1 is associated with various human diseases such as neurological disorders, infections, cardiovascular diseases, liver diseases and cancers. In addition, new advances in the regulation of ULK1 have been identified. Furthermore, targeting ULK1 as a therapeutic strategy for diseases is gaining attention as new corresponding activators or inhibitors are being developed. In this review, we describe the structure and regulation of ULK1 as well as the current targeted activators and inhibitors. Moreover, we highlight the pathological disorders of ULK1 expression and its critical role in human diseases.
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15
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Abstract
Macroautophagy is an evolutionarily conserved process that delivers diverse cellular contents to lysosomes for degradation. As our understanding of this pathway grows, so does our appreciation for its importance in disorders of the CNS. Once implicated primarily in neurodegenerative events owing to acute injury and ageing, macroautophagy is now also linked to disorders of neurodevelopment, indicating that it is essential for both the formation and maintenance of a healthy CNS. In parallel to understanding the significance of macroautophagy across contexts, we have gained a greater mechanistic insight into its physiological regulation and the breadth of cargoes it can degrade. Macroautophagy is a broadly used homeostatic process, giving rise to questions surrounding how defects in this single pathway could cause diseases with distinct clinical and pathological signatures. To address this complexity, we herein review macroautophagy in the mammalian CNS by examining three key features of the process and its relationship to disease: how it functions at a basal level in the discrete cell types of the brain and spinal cord; which cargoes are being degraded in physiological and pathological settings; and how the different stages of the macroautophagy pathway intersect with diseases of neurodevelopment and adult-onset neurodegeneration.
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Affiliation(s)
- Christopher J Griffey
- Doctoral Program in Neurobiology and Behaviour, Medical Scientist Training Program, Columbia University, New York, NY, USA
| | - Ai Yamamoto
- Departments of Neurology, and Pathology and Cell Biology, Columbia University, New York, NY, USA.
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16
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Meng F, Shen F, Ling H, Jin P, Zhou D, Li Q. CircARHGAP12 Triggers Mesenchymal Stromal Cell Autophagy to Facilitate its Effect on Repairing Diabetic Wounds by Sponging miR-301b-3p/ATG16L1 and miR-301b-3p/ULK2. J Invest Dermatol 2022; 142:1976-1989.e4. [PMID: 34933019 DOI: 10.1016/j.jid.2021.11.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 11/07/2021] [Accepted: 11/23/2021] [Indexed: 10/19/2022]
Abstract
Circular RNAs have been confirmed to play vital roles in the development of human diseases. Nevertheless, their effects on modulating mesenchymal stromal cells (MSCs) to heal diabetic wounds are still elusive. In this study, our data revealed that MSCs treated with high glucose displayed an evident reduction in circARHGAP12 expression, whereas autophagy mediated by circARHGAP12 suppressed high glucose-triggered apoptosis of MSCs. Mechanistically, circARHGAP12 was capable of directly interacting with miR-301b-3p and subsequently sponged microRNA to modulate the expression of the miR-301b-3p target genes ATG16L1 and ULK2 and the downstream signaling pathway. Moreover, circARHGAP12 promoted the survival of MSCs in diabetic wounds in vivo and accelerated wound healing. Collectively, these results suggest that circARHGAP12/miR-301b-3p/ATG16L1 and circARHGAP12/miR-301b-3p/ULK2 regulatory networks might be an underlying therapeutic target for MSCs in diabetic wound healing.
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Affiliation(s)
- Fandong Meng
- Department of Endocrinology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China; Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Fengjie Shen
- Department of Endocrinology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China; Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Hongwei Ling
- Department of Endocrinology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Peisheng Jin
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Dongmei Zhou
- Department of Endocrinology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Qiang Li
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.
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17
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Luo S, Zheng N, Lang B. ULK4 in Neurodevelopmental and Neuropsychiatric Disorders. Front Cell Dev Biol 2022; 10:873706. [PMID: 35493088 PMCID: PMC9039724 DOI: 10.3389/fcell.2022.873706] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/29/2022] [Indexed: 11/21/2022] Open
Abstract
The gene Unc51-like kinase 4 (ULK4) belongs to the Unc-51-like serine/threonine kinase family and is assumed to encode a pseudokinase with unclear function. Recently, emerging evidence has suggested that ULK4 may be etiologically involved in a spectrum of neuropsychiatric disorders including schizophrenia, but the underlying mechanism remains unaddressed. Here, we summarize the key findings of the structure and function of the ULK4 protein to provide comprehensive insights to better understand ULK4-related neurodevelopmental and neuropsychiatric disorders and to aid in the development of a ULK4-based therapeutic strategy.
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Affiliation(s)
- Shilin Luo
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China
- Hunan Provincial Engineering Research Center of Translational Medicine and Innovative Drug, Changsha, China
| | - Nanxi Zheng
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
- *Correspondence: Nanxi Zheng, ; Bing Lang,
| | - Bing Lang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
- *Correspondence: Nanxi Zheng, ; Bing Lang,
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18
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Gundelfinger ED, Karpova A, Pielot R, Garner CC, Kreutz MR. Organization of Presynaptic Autophagy-Related Processes. Front Synaptic Neurosci 2022; 14:829354. [PMID: 35368245 PMCID: PMC8968026 DOI: 10.3389/fnsyn.2022.829354] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 01/04/2022] [Indexed: 11/13/2022] Open
Abstract
Brain synapses pose special challenges on the quality control of their protein machineries as they are far away from the neuronal soma, display a high potential for plastic adaptation and have a high energy demand to fulfill their physiological tasks. This applies in particular to the presynaptic part where neurotransmitter is released from synaptic vesicles, which in turn have to be recycled and refilled in a complex membrane trafficking cycle. Pathways to remove outdated and damaged proteins include the ubiquitin-proteasome system acting in the cytoplasm as well as membrane-associated endolysosomal and the autophagy systems. Here we focus on the latter systems and review what is known about the spatial organization of autophagy and endolysomal processes within the presynapse. We provide an inventory of which components of these degradative systems were found to be present in presynaptic boutons and where they might be anchored to the presynaptic apparatus. We identify three presynaptic structures reported to interact with known constituents of membrane-based protein-degradation pathways and therefore may serve as docking stations. These are (i) scaffolding proteins of the cytomatrix at the active zone, such as Bassoon or Clarinet, (ii) the endocytic machinery localized mainly at the peri-active zone, and (iii) synaptic vesicles. Finally, we sketch scenarios, how presynaptic autophagic cargos are tagged and recruited and which cellular mechanisms may govern membrane-associated protein turnover in the presynapse.
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Affiliation(s)
- Eckart D. Gundelfinger
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Institute of Pharmacology and Toxicology, Medical Faculty, Otto von Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Anna Karpova
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Rainer Pielot
- Institute of Pharmacology and Toxicology, Medical Faculty, Otto von Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Craig C. Garner
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
- Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Michael R. Kreutz
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
- Center for Molecular Neurobiology (ZMNH), University Hospital Hamburg-Eppendorf, Hamburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
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19
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Deneubourg C, Ramm M, Smith LJ, Baron O, Singh K, Byrne SC, Duchen MR, Gautel M, Eskelinen EL, Fanto M, Jungbluth H. The spectrum of neurodevelopmental, neuromuscular and neurodegenerative disorders due to defective autophagy. Autophagy 2022; 18:496-517. [PMID: 34130600 PMCID: PMC9037555 DOI: 10.1080/15548627.2021.1943177] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 06/10/2021] [Indexed: 12/15/2022] Open
Abstract
Primary dysfunction of autophagy due to Mendelian defects affecting core components of the autophagy machinery or closely related proteins have recently emerged as an important cause of genetic disease. This novel group of human disorders may present throughout life and comprises severe early-onset neurodevelopmental and more common adult-onset neurodegenerative disorders. Early-onset (or congenital) disorders of autophagy often share a recognizable "clinical signature," including variable combinations of neurological, neuromuscular and multisystem manifestations. Structural CNS abnormalities, cerebellar involvement, spasticity and peripheral nerve pathology are prominent neurological features, indicating a specific vulnerability of certain neuronal populations to autophagic disturbance. A typically biphasic disease course of late-onset neurodegeneration occurring on the background of a neurodevelopmental disorder further supports a role of autophagy in both neuronal development and maintenance. Additionally, an associated myopathy has been characterized in several conditions. The differential diagnosis comprises a wide range of other multisystem disorders, including mitochondrial, glycogen and lysosomal storage disorders, as well as ciliopathies, glycosylation and vesicular trafficking defects. The clinical overlap between the congenital disorders of autophagy and these conditions reflects the multiple roles of the proteins and/or emerging molecular connections between the pathways implicated and suggests an exciting area for future research. Therapy development for congenital disorders of autophagy is still in its infancy but may result in the identification of molecules that target autophagy more specifically than currently available compounds. The close connection with adult-onset neurodegenerative disorders highlights the relevance of research into rare early-onset neurodevelopmental conditions for much more common, age-related human diseases.Abbreviations: AC: anterior commissure; AD: Alzheimer disease; ALR: autophagic lysosomal reformation; ALS: amyotrophic lateral sclerosis; AMBRA1: autophagy and beclin 1 regulator 1; AMPK: AMP-activated protein kinase; ASD: autism spectrum disorder; ATG: autophagy related; BIN1: bridging integrator 1; BPAN: beta-propeller protein associated neurodegeneration; CC: corpus callosum; CHMP2B: charged multivesicular body protein 2B; CHS: Chediak-Higashi syndrome; CMA: chaperone-mediated autophagy; CMT: Charcot-Marie-Tooth disease; CNM: centronuclear myopathy; CNS: central nervous system; DNM2: dynamin 2; DPR: dipeptide repeat protein; DVL3: disheveled segment polarity protein 3; EPG5: ectopic P-granules autophagy protein 5 homolog; ER: endoplasmic reticulum; ESCRT: homotypic fusion and protein sorting complex; FIG4: FIG4 phosphoinositide 5-phosphatase; FTD: frontotemporal dementia; GBA: glucocerebrosidase; GD: Gaucher disease; GRN: progranulin; GSD: glycogen storage disorder; HC: hippocampal commissure; HD: Huntington disease; HOPS: homotypic fusion and protein sorting complex; HSPP: hereditary spastic paraparesis; LAMP2A: lysosomal associated membrane protein 2A; MEAX: X-linked myopathy with excessive autophagy; mHTT: mutant huntingtin; MSS: Marinesco-Sjoegren syndrome; MTM1: myotubularin 1; MTOR: mechanistic target of rapamycin kinase; NBIA: neurodegeneration with brain iron accumulation; NCL: neuronal ceroid lipofuscinosis; NPC1: Niemann-Pick disease type 1; PD: Parkinson disease; PtdIns3P: phosphatidylinositol-3-phosphate; RAB3GAP1: RAB3 GTPase activating protein catalytic subunit 1; RAB3GAP2: RAB3 GTPase activating non-catalytic protein subunit 2; RB1: RB1-inducible coiled-coil protein 1; RHEB: ras homolog, mTORC1 binding; SCAR20: SNX14-related ataxia; SENDA: static encephalopathy of childhood with neurodegeneration in adulthood; SNX14: sorting nexin 14; SPG11: SPG11 vesicle trafficking associated, spatacsin; SQSTM1: sequestosome 1; TBC1D20: TBC1 domain family member 20; TECPR2: tectonin beta-propeller repeat containing 2; TSC1: TSC complex subunit 1; TSC2: TSC complex subunit 2; UBQLN2: ubiquilin 2; VCP: valosin-containing protein; VMA21: vacuolar ATPase assembly factor VMA21; WDFY3/ALFY: WD repeat and FYVE domain containing protein 3; WDR45: WD repeat domain 45; WDR47: WD repeat domain 47; WMS: Warburg Micro syndrome; XLMTM: X-linked myotubular myopathy; ZFYVE26: zinc finger FYVE-type containing 26.
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Affiliation(s)
- Celine Deneubourg
- Department of Basic and Clinical Neuroscience, IoPPN, King’s College London, London, UK
| | - Mauricio Ramm
- Institute of Biomedicine, University of Turku, Turku, Finland
| | - Luke J. Smith
- Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section, King’s College London, London, UK
| | - Olga Baron
- Wolfson Centre for Age-Related Diseases, King’s College London, London, UK
| | - Kritarth Singh
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Susan C. Byrne
- Department of Paediatric Neurology, Neuromuscular Service, Evelina’s Children Hospital, Guy’s & St. Thomas’ Hospital NHS Foundation Trust, London, UK
| | - Michael R. Duchen
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Mathias Gautel
- Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section, King’s College London, London, UK
| | - Eeva-Liisa Eskelinen
- Institute of Biomedicine, University of Turku, Turku, Finland
- Molecular and Integrative Biosciences Research Programme, University of Helsinki, Helsinki, Finland
| | - Manolis Fanto
- Department of Basic and Clinical Neuroscience, IoPPN, King’s College London, London, UK
| | - Heinz Jungbluth
- Department of Basic and Clinical Neuroscience, IoPPN, King’s College London, London, UK
- Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section, King’s College London, London, UK
- Department of Paediatric Neurology, Neuromuscular Service, Evelina’s Children Hospital, Guy’s & St. Thomas’ Hospital NHS Foundation Trust, London, UK
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20
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Kang WS, Lee SM, Hwang D, Park HJ, Kim JW. Association between Unc-51-like autophagy activating kinase 2 gene polymorphisms and schizophrenia in the Korean population. Medicine (Baltimore) 2022; 101:e28745. [PMID: 35119028 PMCID: PMC8812592 DOI: 10.1097/md.0000000000028745] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 01/08/2022] [Indexed: 01/04/2023] Open
Abstract
Accumulating evidence indicates that the autophagy process is involved in the pathogenesis of schizophrenia. Autophagy plays a fundamental role in neuronal survival and function, and autophagy-related genes have been suggested to be associated with the pathogenesis of schizophrenia. The Unc-51-like autophagy activating kinase 2 (ULK2) gene has been implicated in autophagy regulation; therefore, we hypothesized that ULK2 polymorphisms may be associated with schizophrenia susceptibility.This study explored the association between polymorphisms of ULK2 and schizophrenia.Two single nucleotide polymorphisms (SNPs) (rs55730189 and rs150122) of ULK2 were genotyped in 279 patients with schizophrenia and 403 healthy individuals using Fluidigm SNPtype assays. We analyzed the genotype distribution of 2 SNPs and haplotypes between patients with schizophrenia and control subjects.The T allele frequency of rs55730189 showed a significant association between patients with schizophrenia and control subjects (P = .003). Genotype frequencies of rs55710189 were found to be significantly different between patients with schizophrenia and control subjects (odds ratio = 6.89, 95% confidence interval = 1.91-24.90, P < .001 in the dominant model [C/T + T/T vs C/C], OR = 6.50, 95% confidence interval = 1.83-23.01, P < .001 in the log-additive model (C/T vs T/T vs C/C)]. In haplotype analysis, the TT haplotype for these 2 SNPs was significantly associated with schizophrenia (P < .001, χ2 = 12.231).Our findings suggest that specific ULK2 polymorphisms may be associated with susceptibility to schizophrenia in the Korean population.
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Affiliation(s)
- Won Sub Kang
- Department of Neuropsychiatry, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Sang Min Lee
- Department of Neuropsychiatry, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Dongkee Hwang
- Department of Medicine, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Hae Jeong Park
- Department of Pharmacology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Jong Woo Kim
- Department of Neuropsychiatry, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
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21
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Autophagy-related DjAtg1-1 plays critical role in planarian regeneration by regulating proliferation and cell death. Cell Tissue Res 2022; 388:273-286. [PMID: 35107621 DOI: 10.1007/s00441-022-03591-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 01/19/2022] [Indexed: 11/02/2022]
Abstract
Autophagy is an intracellular degradation process and plays key roles in energy recycle and homeostasis maintenance during planarian regeneration. Although planarians provide an ideal model organism for studying autophagy in vivo, the molecular mechanism of planarian autophagy is still unknown. Here, we identify three autophagy-related (Atg) gene 1 homologs from Dugesia japonica and study their roles in planarian regeneration. Both DjATG1-1 and DjATG1-2 proteins show homology to vertebrate unc-51 like autophagy activating kinase 1 (ULK1) and ULK2, DjATG1-3 shows homology to vertebrate ULK3. In contrast to the ubiquitously expressed DjAtg1-1 and DjAtg1-3, DjAtg1-2 is mainly expressed in the intestine branches and epidermis. All the three DjAtg1s can respond to planarian regeneration and starvation. Both DjAtg1-1 and DjAtg1-2 are expressed in the reproductive organs of the starved sexual worms. DjAtg1-1 or DjAtg1-3 RNAi leads to head lysis and death of starved planarians, accompanied by exhaustion of neoblasts. DjAtg1-1 RNAi causes autophagy and regeneration defects and decreases proliferation and cell death; both DjAtg1-2 and DjAtg1-3 RNAi cause no autophagy or regeneration defect but increase cell death during regeneration. Our findings uncover the roles of DjAtg1s in autophagy and regeneration of planarian and highlight the links between proliferation, cell death, and autophagy during regeneration.
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22
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Yang D, Wu X, Wang W, Zhou Y, Wang Z. Ciliary Type III Adenylyl Cyclase in the VMH Is Crucial for High-Fat Diet-Induced Obesity Mediated by Autophagy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2102568. [PMID: 34783461 PMCID: PMC8787410 DOI: 10.1002/advs.202102568] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Neuronal primary cilia are crucial for body weight maintenance. Type III adenylyl cyclase (AC3) is abundantly enriched in neuronal cilia, and mice with global AC3 ablation are obese. However, whether AC3 regulates body weight through its ciliary expression and the mechanism underlying this potential regulation are not clear. In this study, humanized AC3 knock-in mice that are resistant to high-fat diet (HFD)-induced obesity are generated, and increases in the number and length of cilia in the ventromedial hypothalamus (VMH) are shown. It is demonstrated that mice with specifically knocked down ciliary AC3 expression in the VMH show pronounced HFD-induced obesity. In addition, in vitro and in vivo analyses of the VMH show that ciliary AC3 regulates autophagy by binding an autophagy-related gene, gamma-aminobutyric acid A receptor-associated protein (GABARAP). Mice with GABARAP knockdown in the VMH exhibit exacerbated HFD-induced obesity. Overall, the findings may reveal a potential mechanism by which ciliary AC3 expression regulates body weight in the mouse VMH.
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Affiliation(s)
- Dong Yang
- College of Life ScienceInstitute of Life Science and Green DevelopmentHebei UniversityBaodingHebei071002China
| | - Xiangbo Wu
- College of Life ScienceInstitute of Life Science and Green DevelopmentHebei UniversityBaodingHebei071002China
| | - Weina Wang
- College of Life ScienceInstitute of Life Science and Green DevelopmentHebei UniversityBaodingHebei071002China
| | - Yanfen Zhou
- College of Life ScienceInstitute of Life Science and Green DevelopmentHebei UniversityBaodingHebei071002China
| | - Zhenshan Wang
- College of Life ScienceInstitute of Life Science and Green DevelopmentHebei UniversityBaodingHebei071002China
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23
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Drake JC, Wilson RJ, Cui D, Guan Y, Kundu M, Zhang M, Yan Z. Ulk1, Not Ulk2, Is Required for Exercise Training-Induced Improvement of Insulin Response in Skeletal Muscle. Front Physiol 2021; 12:732308. [PMID: 34658916 PMCID: PMC8514673 DOI: 10.3389/fphys.2021.732308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/26/2021] [Indexed: 11/13/2022] Open
Abstract
Unc51 like autophagy activating kinase 1 (Ulk1), the primary autophagy regulator, has been linked to metabolic adaptation in skeletal muscle to exercise training. Here we compared the roles of Ulk1 and homologous Ulk2 in skeletal muscle insulin action following exercise training to gain more mechanistic insights. Inducible, skeletal muscle-specific Ulk1 knock-out (Ulk1-iMKO) mice and global Ulk2 knock-out (Ulk2–/–) mice were subjected to voluntary wheel running for 6 weeks followed by assessment of exercise capacity, glucose tolerance, and insulin signaling in skeletal muscle after a bolus injection of insulin. Both Ulk1-iMKO and Ulk2–/– mice had improved endurance exercise capacity post-exercise. Ulk1-iMKO did not improve glucose clearance during glucose tolerance test, while Ulk2–/– had only marginal improvement. However, exercise training-induced improvement of insulin action in skeletal muscle, indicated by Akt-S473 phosphorylation, was only impaired in Ulk1-iMKO. These data suggest that Ulk1, but not Ulk2, is required for exercise training-induced improvement of insulin action in skeletal muscle, implicating crosstalk between catabolic and anabolic signaling as integral to metabolic adaptation to energetic stress.
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Affiliation(s)
- Joshua C Drake
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States.,Center for Skeletal Muscle Research, The Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Rebecca J Wilson
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, United States.,Department of Biochemistry, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Di Cui
- Center for Skeletal Muscle Research, The Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Yuntian Guan
- Center for Skeletal Muscle Research, The Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States.,Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Mondira Kundu
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Mei Zhang
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States.,Center for Skeletal Muscle Research, The Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Zhen Yan
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States.,Center for Skeletal Muscle Research, The Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States.,Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, United States.,Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, United States
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Plasmalogens regulate the AKT-ULK1 signaling pathway to control the position of the axon initial segment. Prog Neurobiol 2021; 205:102123. [PMID: 34302896 DOI: 10.1016/j.pneurobio.2021.102123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 06/11/2021] [Accepted: 07/14/2021] [Indexed: 01/04/2023]
Abstract
The axon initial segment (AIS) is a specialized region in neurons that encompasses two essential functions, the generation of action potentials and the regulation of the axodendritic polarity. The mechanism controlling the position of the axon initial segment to allow plasticity and regulation of neuron excitability is unclear. Here we demonstrate that plasmalogens, the most abundant ether-phospholipid, are essential for the homeostatic positioning of the AIS. Plasmalogen deficiency is a hallmark of Rhizomelic Chondrodysplasia Punctata (RCDP) and Zellweger spectrum disorders, but Alzheimer's and Parkinson's disease, are also characterized by plasmalogen defects. Neurons lacking plasmalogens displaced the AIS to more distal positions and were characterized by reduced excitability. Treatment with a short-chain alkyl glycerol was able to rescue AIS positioning. Plasmalogen deficiency impaired AKT activation, and we show that inhibition of AKT phosphorylation at Ser473 and Thr308 is sufficient to induce a distal relocation of the AIS. Pathway analysis revealed that downstream of AKT, overtly active ULK1 mediates AIS repositioning. Rescuing the impaired AKT signaling pathway was able to normalize AIS position independently of the biochemical defect. These results unveil a previously unknown mechanism that couples the phospholipid composition of the neuronal membrane to the positional assembly of the AIS.
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25
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Mercer TJ, Ohashi Y, Boeing S, Jefferies HBJ, De Tito S, Flynn H, Tremel S, Zhang W, Wirth M, Frith D, Snijders AP, Williams RL, Tooze SA. Phosphoproteomic identification of ULK substrates reveals VPS15-dependent ULK/VPS34 interplay in the regulation of autophagy. EMBO J 2021; 40:e105985. [PMID: 34121209 PMCID: PMC8280838 DOI: 10.15252/embj.2020105985] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 03/29/2021] [Accepted: 04/21/2021] [Indexed: 02/06/2023] Open
Abstract
Autophagy is a process through which intracellular cargoes are catabolised inside lysosomes. It involves the formation of autophagosomes initiated by the serine/threonine kinase ULK and class III PI3 kinase VPS34 complexes. Here, unbiased phosphoproteomics screens in mouse embryonic fibroblasts deleted for Ulk1/2 reveal that ULK loss significantly alters the phosphoproteome, with novel high confidence substrates identified including VPS34 complex member VPS15 and AMPK complex subunit PRKAG2. We identify six ULK-dependent phosphorylation sites on VPS15, mutation of which reduces autophagosome formation in cells and VPS34 activity in vitro. Mutation of serine 861, the major VPS15 phosphosite, decreases both autophagy initiation and autophagic flux. Analysis of VPS15 knockout cells reveals two novel ULK-dependent phenotypes downstream of VPS15 removal that can be partially recapitulated by chronic VPS34 inhibition, starvation-independent accumulation of ULK substrates and kinase activity-regulated recruitment of autophagy proteins to ubiquitin-positive structures.
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Affiliation(s)
| | | | - Stefan Boeing
- Bioinformatics and BiostatisticsThe Francis Crick InstituteLondonUK
| | | | - Stefano De Tito
- Molecular Cell Biology of AutophagyThe Francis Crick InstituteLondonUK
- Institute of Experimental Endocrinology and Oncology (IEOS)National Research CouncilNaplesItaly
| | - Helen Flynn
- Institute of Experimental Endocrinology and Oncology (IEOS)National Research CouncilNaplesItaly
| | | | - Wenxin Zhang
- Molecular Cell Biology of AutophagyThe Francis Crick InstituteLondonUK
| | - Martina Wirth
- Molecular Cell Biology of AutophagyThe Francis Crick InstituteLondonUK
| | - David Frith
- ProteomicsThe Francis Crick InstituteLondonUK
| | | | | | - Sharon A Tooze
- Molecular Cell Biology of AutophagyThe Francis Crick InstituteLondonUK
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26
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Wirth M, Mouilleron S, Zhang W, Sjøttem E, Princely Abudu Y, Jain A, Lauritz Olsvik H, Bruun JA, Razi M, Jefferies HB, Lee R, Joshi D, O'Reilly N, Johansen T, Tooze SA. Phosphorylation of the LIR Domain of SCOC Modulates ATG8 Binding Affinity and Specificity. J Mol Biol 2021; 433:166987. [DOI: https:/doi.org/10.1016/j.jmb.2021.166987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
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27
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Crawley O, Grill B. Autophagy in axonal and presynaptic development. Curr Opin Neurobiol 2021; 69:139-148. [PMID: 33940492 DOI: 10.1016/j.conb.2021.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/17/2021] [Accepted: 03/21/2021] [Indexed: 10/21/2022]
Abstract
The study of autophagy in the nervous system has predominantly centered on degeneration. Evidence is now cementing crucial roles for autophagy in neuronal development and growth, especially in axonal and presynaptic compartments. A picture is emerging that autophagy typically promotes the growth of axons and reduces presynaptic stability. Nonetheless, these are not rigid principles, and it remains unclear why autophagy does not always display these relationships during axonal and presynaptic development. Recent progress has identified mechanisms underlying spatiotemporal control of autophagy in neurons and begun to unravel how autophagy is integrated with other cellular processes, such as proteasomal degradation and axon guidance. Ultimately, understanding how autophagy is regulated and its role in the developing nervous system is key to comprehending how the nervous system assembles its stereotyped yet plastic configuration. It is also likely to inform how we think about neurodevelopmental disorders and neurodegenerative diseases.
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Affiliation(s)
- Oliver Crawley
- Unidad de Neurobiología Celular y de Sistemas, Instituto de Neurociencias (CSIC-UMH), San Juan de Alicante, 03550, Spain.
| | - Brock Grill
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, 98199, USA; Department of Pediatrics, University of Washington School of Medicine, Seattle, WA, USA; Department of Pharmacology, University of Washington School of Medicine, Seattle, WA, USA.
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28
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Phosphorylation of the LIR Domain of SCOC Modulates ATG8 Binding Affinity and Specificity. J Mol Biol 2021; 433:166987. [PMID: 33845085 PMCID: PMC8202330 DOI: 10.1016/j.jmb.2021.166987] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 03/27/2021] [Accepted: 04/04/2021] [Indexed: 12/15/2022]
Abstract
Autophagy is a highly conserved degradative pathway, essential for cellular homeostasis and implicated in diseases including cancer and neurodegeneration. Autophagy-related 8 (ATG8) proteins play a central role in autophagosome formation and selective delivery of cytoplasmic cargo to lysosomes by recruiting autophagy adaptors and receptors. The LC3-interacting region (LIR) docking site (LDS) of ATG8 proteins binds to LIR motifs present in autophagy adaptors and receptors. LIR-ATG8 interactions can be highly selective for specific mammalian ATG8 family members (LC3A-C, GABARAP, and GABARAPL1-2) and how this specificity is generated and regulated is incompletely understood. We have identified a LIR motif in the Golgi protein SCOC (short coiled-coil protein) exhibiting strong binding to GABARAP, GABARAPL1, LC3A and LC3C. The residues within and surrounding the core LIR motif of the SCOC LIR domain were phosphorylated by autophagy-related kinases (ULK1-3, TBK1) increasing specifically LC3 family binding. More distant flanking residues also contributed to ATG8 binding. Loss of these residues was compensated by phosphorylation of serine residues immediately adjacent to the core LIR motif, indicating that the interactions of the flanking LIR regions with the LDS are important and highly dynamic. Our comprehensive structural, biophysical and biochemical analyses support and provide novel mechanistic insights into how phosphorylation of LIR domain residues regulates the affinity and binding specificity of ATG8 proteins towards autophagy adaptors and receptors.
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29
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The Autophagy-Initiating Protein Kinase ULK1 Phosphorylates Human Cytomegalovirus Tegument Protein pp28 and Regulates Efficient Virus Release. J Virol 2021; 95:JVI.02346-20. [PMID: 33328309 DOI: 10.1128/jvi.02346-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
Autophagy is a catabolic process contributing to intrinsic cellular defense by degrading viral particles or proteins; however, several viruses hijack this pathway for their own benefit. The role of autophagy during human cytomegalovirus (HCMV) replication has not been definitely clarified yet. Utilizing small interfering RNA (siRNA)-based screening, we observed that depletion of many autophagy-related proteins resulted in reduced virus release, suggesting a requirement of autophagy-related factors for efficient HCMV replication. Additionally, we could show that the autophagy-initiating serine/threonine protein kinase ULK1 as well as other constituents of the ULK1 complex were upregulated at early times of infection and stayed upregulated throughout the replication cycle. We demonstrate that indirect interference with ULK1 through inhibition of the upstream regulator AMP-activated protein kinase (AMPK) impaired virus release. Furthermore, this result was verified by direct abrogation of ULK1 kinase activity utilizing the ULK1-specific kinase inhibitors SBI-0206965 and ULK-101. Analysis of viral protein expression in the presence of ULK-101 revealed a connection between the cellular kinase ULK1 and the viral tegument protein pp28 (pUL99), and we identified pp28 as a novel viral substrate of ULK1 by in vitro kinase assays. In the absence of ULK1 kinase activity, large pp28- and pp65-positive structures could be detected in the cytoplasm at late time points of infection. Transmission electron microscopy demonstrated that these structures represent large perinuclear protein accumulations presumably representing aggresomes. Our results indicate that HCMV manipulates ULK1 and further components of the autophagic machinery to ensure the efficient release of viral particles.IMPORTANCE The catabolic program of autophagy represents a powerful immune defense against viruses that is, however, counteracted by antagonizing viral factors. Understanding the exact interplay between autophagy and HCMV infection is of major importance since autophagy-related proteins emerged as promising targets for pharmacologic intervention. Our study provides evidence for a proviral role of several autophagy-related proteins suggesting that HCMV has developed strategies to usurp components of the autophagic machinery for its own benefit. In particular, we observed strong upregulation of the autophagy-initiating protein kinase ULK1 and further components of the ULK1 complex during HCMV replication. In addition, both siRNA-mediated depletion of ULK1 and interference with ULK1 protein kinase activity by two chemically different inhibitors resulted in impaired viral particle release. Thus, we propose that ULK1 kinase activity is required for efficient HCMV replication and thus represents a promising novel target for future antiviral drug development.
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30
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Axonal Organelles as Molecular Platforms for Axon Growth and Regeneration after Injury. Int J Mol Sci 2021; 22:ijms22041798. [PMID: 33670312 PMCID: PMC7918155 DOI: 10.3390/ijms22041798] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/06/2021] [Accepted: 02/08/2021] [Indexed: 02/06/2023] Open
Abstract
Investigating the molecular mechanisms governing developmental axon growth has been a useful approach for identifying new strategies for boosting axon regeneration after injury, with the goal of treating debilitating conditions such as spinal cord injury and vision loss. The picture emerging is that various axonal organelles are important centers for organizing the molecular mechanisms and machinery required for growth cone development and axon extension, and these have recently been targeted to stimulate robust regeneration in the injured adult central nervous system (CNS). This review summarizes recent literature highlighting a central role for organelles such as recycling endosomes, the endoplasmic reticulum, mitochondria, lysosomes, autophagosomes and the proteasome in developmental axon growth, and describes how these organelles can be targeted to promote axon regeneration after injury to the adult CNS. This review also examines the connections between these organelles in developing and regenerating axons, and finally discusses the molecular mechanisms within the axon that are required for successful axon growth.
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31
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Wang H, Sun G, Xu P, Lv J, Zhang X, Zhang L, Wang S, Cao J, Xia Y, Xuan Z, Li B, Huang X, Jiang T, Fang L, Xu Z. Circular RNA TMEM87A promotes cell proliferation and metastasis of gastric cancer by elevating ULK1 via sponging miR-142-5p. J Gastroenterol 2021; 56:125-138. [PMID: 33155080 DOI: 10.1007/s00535-020-01744-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/20/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Circular RNAs (circRNAs) act as vital regulators of gene expression in a variety of cancers. However, the role of circRNAs in gastric cancer (GC) remains largely unexplored. Herein, we identified that circTMEM87A sponges miR-142-5p to promote GC progression through up-regulating ULK1 expression. METHODS The expression of circTMEM87A in GC was determined by RNA sequencing and quantitative real-time PCR (qRT-PCR). The effects of knockdown or exogenous expression of circTMEM87A on GC cell phenotypes were evaluated both in vitro and in vivo. The interacting miRNA of circTMEM87A was predicted by bioinformatics and confirmed by RNA pull-down, dual-luciferase reporter assay and fluorescence in situ hybridization (FISH). The mechanism by which circTMEM87A/miR-142-5p/ULK1 axis promotes GC was determined by western blot, GFP/mRFP-LC3 puncta analysis, transmission electron microscope (TEM). RESULTS CircTMEM87A was dramatically elevated in GC tissues and cell lines, and high circTMEM87A expression was closely correlated with poor prognosis of GC patients. Knockdown of circTMEM87A suppressed cell growth, migration, invasion and induced apoptosis in vitro, as well as inhibited GC tumorigenicity and lung metastasis potential in vivo. Meanwhile, circTMEM87A overexpression had the opposite effects. Furthermore, we demonstrated that circTMEM87A could act as a sponge of miR-142-5p to regulate ULK1 expression and GC progression. CONCLUSIONS Our findings suggest that circTMEM87A functions as an oncogene through the miR-142-5p/ULK1 axis in GC. CircTMEM87A might be a prognostic biomarker as well as a promising therapeutic target for GC.
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Affiliation(s)
- Haixiao Wang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
- Department of General Surgery, The Affiliated Huaian No.1 People's Hospital of Nanjing Medical University, Huaian, 223300, Jiangsu, China
| | - Guangli Sun
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Penghui Xu
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Jialun Lv
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Xing Zhang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Lu Zhang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Sen Wang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Jiacheng Cao
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Yiwen Xia
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Zhe Xuan
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Bowen Li
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Xiaoxu Huang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Tianlu Jiang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Lang Fang
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Zekuan Xu
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
- Collaborative Innovation Center For Cancer Personalized Medicine, Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
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Vahsen BF, Lingor P. ULK1 as a novel therapeutic target in neurodegeneration. Neural Regen Res 2021; 16:1212-1213. [PMID: 33269781 PMCID: PMC8224110 DOI: 10.4103/1673-5374.300442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Björn Friedhelm Vahsen
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK; Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Paul Lingor
- Department of Neurology, University Medical Center Göttingen, Göttingen; Center for Biostructural Imaging of Neurodegeneration (BIN), DFG Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University Medical Center Göttingen, Göttingen; Department of Neurology, Rechts der Isar Hospital of the Technical University Munich, Munich, Germany
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33
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Koomar T, Thomas TR, Pottschmidt NR, Lutter M, Michaelson JJ. Estimating the Prevalence and Genetic Risk Mechanisms of ARFID in a Large Autism Cohort. Front Psychiatry 2021; 12:668297. [PMID: 34177659 PMCID: PMC8221394 DOI: 10.3389/fpsyt.2021.668297] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/07/2021] [Indexed: 12/27/2022] Open
Abstract
This study is the first genetically-informed investigation of avoidant/restrictive food intake disorder (ARFID), an eating disorder that profoundly impacts quality of life for those affected. ARFID is highly comorbid with autism, and we provide the first estimate of its prevalence in a large and phenotypically diverse autism cohort (a subsample of the SPARK study, N = 5,157 probands). This estimate, 21% (at a balanced accuracy 80%), is at the upper end of previous estimates from studies based on clinical samples, suggesting under-diagnosis and potentially lack of awareness among caretakers and clinicians. Although some studies suggest a decrease of disordered eating symptoms by age 6, our estimates indicate that up to 17% (at a balanced accuracy 87%) of parents of autistic children are also at heightened risk for ARFID, suggesting a lifelong risk for disordered eating. We were also able to provide the first estimates of narrow-sense heritability (h2) for ARFID risk, at 0.45. Genome-wide association revealed a single hit near ZSWIM6, a gene previously implicated in neurodevelopmental conditions. While, the current sample was not well-powered for GWAS, effect size and heritability estimates allowed us to project the sample sizes necessary to more robustly discover ARFID-linked loci via common variants. Further genetic analysis using polygenic risk scores (PRS) affirmed genetic links to autism as well as neuroticism and metabolic syndrome.
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Affiliation(s)
- Tanner Koomar
- Department of Psychiatry, The University of Iowa, Iowa City, IA, United States
| | - Taylor R Thomas
- Department of Psychiatry, The University of Iowa, Iowa City, IA, United States
| | - Natalie R Pottschmidt
- Department of Psychology, Pennsylvania State University, State College, PA, United States
| | - Michael Lutter
- Eating Recovery Center of San Antonio, San Antonio, TX, United States
| | - Jacob J Michaelson
- Department of Psychiatry, The University of Iowa, Iowa City, IA, United States
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34
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Remodeling without destruction: non-proteolytic ubiquitin chains in neural function and brain disorders. Mol Psychiatry 2021; 26:247-264. [PMID: 32709994 PMCID: PMC9229342 DOI: 10.1038/s41380-020-0849-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 07/08/2020] [Accepted: 07/14/2020] [Indexed: 12/31/2022]
Abstract
Ubiquitination is a fundamental posttranslational protein modification that regulates diverse biological processes, including those in the CNS. Several topologically and functionally distinct polyubiquitin chains can be assembled on protein substrates, modifying their fates. The classical and most prevalent polyubiquitin chains are those that tag a substrate to the proteasome for degradation, which has been established as a major mechanism driving neural circuit deconstruction and remodeling. In contrast, proteasome-independent non-proteolytic polyubiquitin chains regulate protein scaffolding, signaling complex formation, and kinase activation, and play essential roles in an array of signal transduction processes. Despite being a cornerstone in immune signaling and abundant in the mammalian brain, these non-proteolytic chains are underappreciated in neurons and synapses in the brain. Emerging studies have begun to generate exciting insights about some fundamental roles played by these non-degradative chains in neuronal function and plasticity. In addition, their roles in a number of brain diseases are being recognized. In this article, we discuss recent advances on these nonconventional ubiquitin chains in neural development, function, plasticity, and related pathologies.
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35
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Errichiello E, Giorda R, Gambale A, Iolascon A, Zuffardi O, Giglio S. RB1CC1 duplication and aberrant overexpression in a patient with schizophrenia: further phenotype delineation and proposal of a pathogenetic mechanism. Mol Genet Genomic Med 2020; 9:e1561. [PMID: 33340270 PMCID: PMC7963413 DOI: 10.1002/mgg3.1561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 11/20/2020] [Accepted: 11/05/2020] [Indexed: 12/26/2022] Open
Abstract
Background Copy number variants in coding and noncoding genomic regions have been implicated as risk factor for schizophrenia (SCZ). Rare duplications of the RB1CC1 gene were found enriched in SCZ patients. Considering that the effect of such duplications on RB1CC1 expression has never been evaluated and partial gene duplications of RB1CC1 have also been reported in SCZ patients, it is unclear whether the pathogenesis is mediated by haploinsufficiency rather than genuine overexpression of the gene. Methods and Results We studied a patient with schizophrenia, suicidality, and obesity, who carried a de novo RB1CC1 complete duplication, as assessed by high‐resolution array‐CGH. Molecular breakpoint cloning allowed to identify nonhomologous end joining (NHEJ) as driving mechanism in this rearrangement. On the contrary, trio‐based whole‐exome sequencing excluded other potential causative variants related to the phenotype. Functional assays showed significant overexpression of RB1CC1 in the peripheral blood lymphocytes of the proband compared to control subjects, suggesting overdosage as leading mechanism in SCZ pathophysiology. Conclusion We hypothesized a pathogenetic model that might explain the correlation between RB1CC1 overexpression and schizophrenia by altering different cell signaling pathways, including autophagy, a promising therapeutic target for schizophrenic patients.
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Affiliation(s)
- Edoardo Errichiello
- Unit of Medical Genetics, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Roberto Giorda
- Laboratory of Molecular Biology, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Antonella Gambale
- Department of Molecular Medicine and Medical Biotechnologies, University "Federico II" of Naples, Naples, Italy.,CEINGE, Advanced Biotechnologies, Naples, Italy
| | - Achille Iolascon
- Department of Molecular Medicine and Medical Biotechnologies, University "Federico II" of Naples, Naples, Italy.,CEINGE, Advanced Biotechnologies, Naples, Italy
| | - Orsetta Zuffardi
- Unit of Medical Genetics, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Sabrina Giglio
- Unit of Medical Genetics, Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
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36
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Liu W, Li K, Wang G, Yang L, Qu Q, Fan Z, Sun Y, Huang J, Miao Y, Hu Z. Impairment of autophagy may be associated with follicular miniaturization in androgenetic alopecia by inducing premature catagen. J Dermatol 2020; 48:289-300. [PMID: 33258150 DOI: 10.1111/1346-8138.15672] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 10/04/2020] [Indexed: 12/16/2022]
Abstract
Androgenetic alopecia is the most common form of hair loss disorder. The features of this process are shortening of the anagen phase in hair cycling and progressive miniaturization of the hair follicle. However, the mechanisms in androgenetic alopecia are still unclear, and the treatment methods are also limited. Therefore, further study on the pathogenesis and new therapies for androgenetic alopecia are urgently needed. In this study, we found that endogenous autophagy was severely impaired, accompanied by increased apoptosis in early catagen-like miniaturized hair follicles from the balding scalps of androgenetic alopecia patients. Moreover, inhibition of autophagy using 3-methyladenine could induce apoptosis, premature hair follicle regression and slow down the hair growth in organ-cultured hair follicles. Taken together, these results suggest that impairment of autophagy could be a potential mechanism in androgenetic alopecia.
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Affiliation(s)
- Weiwen Liu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China.,Laboratory for Tissue Microenvironment, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan
| | - Kaitao Li
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Gaofeng Wang
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China.,Department of Dermatology, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Lunan Yang
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Qian Qu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Zhexiang Fan
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Yang Sun
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Junfei Huang
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Yong Miao
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Zhiqi Hu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, China
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37
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Lim J, Murthy A. Targeting Autophagy to Treat Cancer: Challenges and Opportunities. Front Pharmacol 2020; 11:590344. [PMID: 33381037 PMCID: PMC7768823 DOI: 10.3389/fphar.2020.590344] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 10/09/2020] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a catabolic process that targets its cargo for lysosomal degradation. In addition to its function in maintaining tissue homeostasis, autophagy is recognized to play a context-dependent role in cancer. Autophagy may inhibit tumor initiation under specific contexts; however, a growing body of evidence supports a pro-tumorigenic role of this pathway in established disease. In this setting, autophagy drives treatment resistance, metabolic changes, and immunosuppression both in a tumor-intrinsic and extrinsic manner. This observation has prompted renewed interest in targeting autophagy for cancer therapy. Novel genetic models have proven especially insightful, revealing unique and overlapping roles of individual autophagy-related genes in tumor progression. Despite identification of pharmacologically actionable nodes in the pathway, fundamental challenges still exist for successful therapeutic inhibition of autophagy. Here we summarize the current understanding of autophagy as a driver of resistance against targeted and immuno-therapies and highlight knowledge gaps that, if addressed, may provide meaningful advances in the treatment of cancer.
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Affiliation(s)
| | - Aditya Murthy
- Department of Cancer Immunology, Genentech, Inc., South San Francisco, CA, United States
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38
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Yuan XL, Li XQ, Xu K, Hou XD, Zhang ZF, Xue L, Liu XM, Zhang P. Transcriptome Profiling and Cytological Assessments for Identifying Regulatory Pathways Associated With Diorcinol N-Induced Autophagy in A3 Cells. Front Pharmacol 2020; 11:570450. [PMID: 33178020 PMCID: PMC7593552 DOI: 10.3389/fphar.2020.570450] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/09/2020] [Indexed: 12/11/2022] Open
Abstract
Fungal secondary metabolites serve as a rich resource for exploring lead compounds with medicinal importance. Diorcinol N (DN), a fungal secondary metabolite isolated from an endophytic fungus, Arthrinium arundinis, exhibits robust anticancer activity. However, the anticancer mechanism of DN remains unclear. In this study, we examined the growth-inhibitory effect of DN on different human cancer cell lines. We found that DN decreased the viability of A3 T-cell leukemia cells in a time- and concentration-dependent manner. Transcriptome analysis indicated that DN modulated the transcriptome of A3 cells. In total, 9,340 differentially expressed genes were found, among which 4,378 downregulated genes and 4,962 upregulated genes were mainly involved in autophagy, cell cycle, and DNA replication. Furthermore, we demonstrated that DN induced autophagy, cell cycle arrest in the G1/S phase, and downregulated the expression of autophagy- and cell cycle-related genes in A3 cells. By labeling A3 cells with acridine orange/ethidium bromide, Hoechst 33,258, and monodansylcadaverine and via transmission electron microscopy, we found that DN increased plasma membrane permeability, structural disorganization, vacuolation, and autophagosome formation. Our study provides evidence for the mechanism of anticancer activity of DN in T-cell leukemia (A3) cells and demonstrates the promise of DN as a lead or even candidate molecule for the treatment of acute lymphoblastic leukemia.
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Affiliation(s)
- Xiao-Long Yuan
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Xiu-Qi Li
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China.,Graduate School of Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kuo Xu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Xiao-Dong Hou
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Zhong-Feng Zhang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Lin Xue
- Wannan Tobacco Group Company Limited, Xuancheng, China
| | - Xin-Min Liu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Peng Zhang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
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39
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Adnan G, Rubikaite A, Khan M, Reber M, Suetterlin P, Hindges R, Drescher U. The GTPase Arl8B Plays a Principle Role in the Positioning of Interstitial Axon Branches by Spatially Controlling Autophagosome and Lysosome Location. J Neurosci 2020; 40:8103-8118. [PMID: 32917789 PMCID: PMC7574663 DOI: 10.1523/jneurosci.1759-19.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 07/13/2020] [Accepted: 07/20/2020] [Indexed: 12/12/2022] Open
Abstract
Interstitial axon branching is an essential step during the establishment of neuronal connectivity. However, the exact mechanisms on how the number and position of branches are determined are still not fully understood. Here, we investigated the role of Arl8B, an adaptor molecule between lysosomes and kinesins. In chick retinal ganglion cells (RGCs), downregulation of Arl8B reduces axon branch density and shifts their location more proximally, while Arl8B overexpression leads to increased density and more distal positions of branches. These alterations correlate with changes in the location and density of lysosomes and autophagosomes along the axon shaft. Diminishing autophagy directly by knock-down of atg7, a key autophagy gene, reduces branch density, while induction of autophagy by rapamycin increases axon branching, indicating that autophagy plays a prominent role in axon branch formation. In vivo, local inactivation of autophagy in the retina using a mouse conditional knock-out approach disturbs retino-collicular map formation which is dependent on the formation of interstitial axon branches. These data suggest that Arl8B plays a principal role in the positioning of axon branches by spatially controlling autophagy, thus directly controlling formation of neural connectivity in the brain.SIGNIFICANCE STATEMENT The formation of interstitial axonal branches plays a prominent role in numerous places of the developing brain during neural circuit establishment. We show here that the GTPase Arl8B controls density and location of interstitial axon branches, and at the same time controls also density and location of the autophagy machinery. Upregulation or downregulation of autophagy in vitro promotes or inhibits axon branching. Local disruption of autophagy in vivo disturbs retino-collicular mapping. Our data suggest that Arl8B controls axon branching by controlling locally autophagy. This work is one of the first reports showing a role of autophagy during early neural circuit development and suggests that autophagy in general plays a much more prominent role during brain development than previously anticipated.
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Affiliation(s)
- Gee Adnan
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, United Kingdom
| | - Aine Rubikaite
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, United Kingdom
| | - Moqadisa Khan
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, United Kingdom
| | - Michael Reber
- Krembil Research Institute, Toronto, Ontario M5T 0S8, Canada
| | - Philip Suetterlin
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, United Kingdom
- Craniofacial Development and Stem Cell Biology, King's College London, Guy's Hospital, London SE1 9RT, United Kingdom
| | - Robert Hindges
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London SE1 1UL, United Kingdom
| | - Uwe Drescher
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London SE1 1UL, United Kingdom
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40
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Meng X, Li H, Fang E, Feng J, Zhao X. Comparison of Stage 4 and Stage 4s Neuroblastoma Identifies Autophagy-Related Gene and LncRNA Signatures Associated With Prognosis. Front Oncol 2020; 10:1411. [PMID: 32974147 PMCID: PMC7466450 DOI: 10.3389/fonc.2020.01411] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/03/2020] [Indexed: 01/01/2023] Open
Abstract
Background: The spontaneous regression of neuroblastoma (NB) is most prevalent and well-documented in stage 4s NB patients. However, whether autophagy plays roles in the spontaneous regression of NB is unknown. Objective: This study aimed to identify autophagy-related genes (ARGs) and autophagy-related long non-coding RNAs (lncRNAs) differentially expressed in stage 4 and stage 4s NB and to build prognostic risk signatures on the basis of the ARGs and autophagy-related lncRNAs. Methods: One RNA-sequence (RNA-Seq) dataset (TARGET NBL, n = 153) was utilized as discovery cohort, and two microarray datasets (n = 498 and n = 223) were used as validation cohorts. Differentially expressed ARGs were identified by comparing stage 4s and stage 4 NB samples. An ARG signature risk score and an autophagy-related lncRNA signature risk score were constructed. The receiver operating characteristic (ROC) curve analyses were used to evaluate the survival prediction ability of the two signatures. Gene function annotation and Gene Set Enrichment Analysis (GSEA) were performed to clarify the autophagic biological processes enriched in different risk groups. Results: Nine ARGs were integrated into the ARG signature. Patients in the high-risk group of the ARG signature had significantly poorer overall survival (OS) than patients in the low-risk group. The ROC curves analyses revealed that the ARG signature performed very well in predicting OS [5-year area under the curve (AUC) = 0.81]. Seven autophagy-related lncRNAs were integrated into the autophagy-related lncRNA signature. Patients in the high-risk group of the lncRNA signature had significantly poorer OS than patients in the low-risk group. The ROC curve analyses also revealed that the lncRNA signature performed well in predicting OS (5-year AUC = 0.77). Both the ARG signature and lncRNA signature are independent with other clinical risk factors in the multivariate Cox regression survival analyses. GSEAs revealed that autophagy-related biological processes are enriched in low-risk groups. Conclusions: Autophagy-related genes and lncRNAs are differentially expressed between stage 4 and stage 4s NB. The ARG signature and autophagy-related lncRNA signature successfully stratified NB patients into two risk groups. Autophagy-related biological processes are highly enriched in low-risk NB groups.
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Affiliation(s)
- Xinyao Meng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Honglin Li
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Erhu Fang
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiexiong Feng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiang Zhao
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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41
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Singha B, Laski J, Ramos Valdés Y, Liu E, DiMattia GE, Shepherd TG. Inhibiting ULK1 kinase decreases autophagy and cell viability in high-grade serous ovarian cancer spheroids. Am J Cancer Res 2020; 10:1384-1399. [PMID: 32509386 PMCID: PMC7269771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 02/27/2020] [Indexed: 06/11/2023] Open
Abstract
Metastasis in high-grade serous ovarian cancer (HGSOC) occurs through an unconventional route that involves exfoliation of cancer cells from primary tumors and peritoneal dissemination via multicellular clusters or spheroids. Previously, we demonstrated autophagy induction in HGSOC spheroids grown in vitro and in spheroids collected from ovarian cancer patient ascites; thus, we speculate that autophagy may contribute to spheroid cell survival and overall disease progression. Hence, in this study we sought to evaluate whether ULK1 (unc-51-like kinase-1), a serine-threonine kinase critical for stress-induced autophagy, is important for autophagy regulation in HGSOC spheroids. We demonstrate that HGSOC spheroids have increased ULK1 protein expression that parallels autophagy activation. ULK1 knockdown increased p62 accumulation and decreased LC3-II/I ratio in HGSOC spheroids. In addition, knocking down ATG13, a protein that regulates ULK1 activity via complex formation, phenocopied our ULK1 knockdown results. HGSOC spheroids were blocked in autophagic flux due to ULK1 and ATG13 knockdown as determined by an mCherry-eGFP-LC3B fluorescence reporter. These observations were recapitulated when HGSOC spheroids were treated with an ULK1 kinase inhibitor, MRT68921. Autophagy regulation in normal human fallopian tube epithelial FT190 cells, however, may bypass ULK1, since MRT68921 reduced viability in HGSOC spheroids but not in FT190 cells. Interestingly, ULK1 mRNA expression is negatively correlated with patient survival among stage III and stage IV serous ovarian cancer patients. As we observed using established HGSOC cell lines, cultured spheroids using our new, patient-derived HGSOC cells were also sensitive to ULK1 inhibition and demonstrated reduced cell viability to MRT68921 treatment. These results demonstrate the importance of ULK1 for autophagy induction in HGSOC spheroids and therefore justifies further evaluation of MRT68921, and other novel ULK1 inhibitors, as potential therapeutics against metastatic HGSOC.
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Affiliation(s)
- Bipradeb Singha
- The Mary & John Knight Translational Ovarian Cancer Research Unit, London Regional Cancer ProgramLondon, Ontario, Canada
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, Western UniversityLondon, Ontario, Canada
| | - Jeremi Laski
- The Mary & John Knight Translational Ovarian Cancer Research Unit, London Regional Cancer ProgramLondon, Ontario, Canada
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, Western UniversityLondon, Ontario, Canada
| | - Yudith Ramos Valdés
- The Mary & John Knight Translational Ovarian Cancer Research Unit, London Regional Cancer ProgramLondon, Ontario, Canada
| | - Elaine Liu
- The Mary & John Knight Translational Ovarian Cancer Research Unit, London Regional Cancer ProgramLondon, Ontario, Canada
| | - Gabriel E DiMattia
- The Mary & John Knight Translational Ovarian Cancer Research Unit, London Regional Cancer ProgramLondon, Ontario, Canada
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western UniversityLondon, Ontario, Canada
- Department of Oncology, Schulich School of Medicine and Dentistry, The University of Western OntarioLondon, Ontario, Canada
| | - Trevor G Shepherd
- The Mary & John Knight Translational Ovarian Cancer Research Unit, London Regional Cancer ProgramLondon, Ontario, Canada
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, Western UniversityLondon, Ontario, Canada
- Department of Obstetrics & Gynaecology, Schulich School of Medicine and Dentistry, Western UniversityLondon, Ontario, Canada
- Department of Oncology, Schulich School of Medicine and Dentistry, The University of Western OntarioLondon, Ontario, Canada
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42
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Autophagy-Independent Functions of the Autophagy Machinery. Cell 2020; 177:1682-1699. [PMID: 31199916 PMCID: PMC7173070 DOI: 10.1016/j.cell.2019.05.026] [Citation(s) in RCA: 583] [Impact Index Per Article: 145.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/11/2019] [Accepted: 05/13/2019] [Indexed: 02/07/2023]
Abstract
Macroautophagy (herein referred to as autophagy) is an evolutionary ancient mechanism that culminates with the lysosomal degradation of superfluous or potentially dangerous cytosolic entities. Over the past 2 decades, the molecular mechanisms underlying several variants of autophagy have been characterized in detail. Accumulating evidence suggests that most, if not all, components of the molecular machinery for autophagy also mediate autophagy-independent functions. Here, we discuss emerging data on the non-autophagic functions of autophagy-relevant proteins.
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43
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Ivankovic D, Drew J, Lesept F, White IJ, López Doménech G, Tooze SA, Kittler JT. Axonal autophagosome maturation defect through failure of ATG9A sorting underpins pathology in AP-4 deficiency syndrome. Autophagy 2020; 16:391-407. [PMID: 31142229 PMCID: PMC6999640 DOI: 10.1080/15548627.2019.1615302] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 04/02/2019] [Accepted: 04/29/2019] [Indexed: 12/26/2022] Open
Abstract
Adaptor protein (AP) complexes mediate key sorting decisions in the cell through selective incorporation of transmembrane proteins into vesicles. Little is known of the roles of AP-4, despite its loss of function leading to a severe early onset neurological disorder, AP-4 deficiency syndrome. Here we demonstrate an AP-4 epsilon subunit knockout mouse model that recapitulates characteristic neuroanatomical phenotypes of AP-4 deficiency patients. We show that ATG9A, critical for autophagosome biogenesis, is an AP-4 cargo, which is retained within the trans-Golgi network (TGN) in vivo and in culture when AP-4 function is lost. TGN retention results in depletion of axonal ATG9A, leading to defective autophagosome generation and aberrant expansions of the distal axon. The reduction in the capacity to generate axonal autophagosomes leads to defective axonal extension and de novo generation of distal axonal swellings containing accumulated ER, underlying the impaired axonal integrity in AP-4 deficiency syndrome.Abbreviations: AP: adaptor protein; AP4B1: adaptor-related protein complex AP-4, beta 1; AP4E1: adaptor-related protein complex AP-4, epsilon 1; ATG: autophagy-related; EBSS: Earle's balanced salt solution; ER: endoplasmic reticulum; GFAP: glial fibrillary acidic protein; GOLGA1/Golgin-97/GOLG97: golgi autoantigen, golgin subfamily a, 1; GOLGA2/GM130: golgi autoantigen, golgin subfamily a, 2; HSP: hereditary spastic paraplegia; LC3/MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; MAP2: microtubule-associated protein 2; MAPK8IP1/JIP1: mitogen-acitvated protein kinase 8 interacting protein 1; NEFH/NF200: neurofilament, heavy polypeptide; RBFOX3/NeuN (RNA binding protein, fox-1 homolog [C. elegans] 3); SQSTM1/p62: sequestosome 1; TGN: trans-Golgi network; WIPI2: WD repeat domain, phosphoinositide interacting protein 2.
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Affiliation(s)
| | - James Drew
- Neuroscience, Physiology and Pharmacology, UCL, London, UK
| | - Flavie Lesept
- Neuroscience, Physiology and Pharmacology, UCL, London, UK
| | - Ian J. White
- MRC Laboratory for Molecular Cell Biology, UCL, London, UK
| | | | - Sharon A. Tooze
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, London, UK
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Tyra LK, Nandi N, Tracy C, Krämer H. Yorkie Growth-Promoting Activity Is Limited by Atg1-Mediated Phosphorylation. Dev Cell 2020; 52:605-616.e7. [PMID: 32032548 DOI: 10.1016/j.devcel.2020.01.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/26/2019] [Accepted: 01/09/2020] [Indexed: 01/31/2023]
Abstract
The expression of multiple growth-promoting genes is coordinated by the transcriptional co-activator Yorkie with its major regulatory input provided by the Hippo-Warts kinase cascade. Here, we identify Atg1/ULK1-mediated phosphorylation of Yorkie as an additional inhibitory input independent of the Hippo-Warts pathway. Two serine residues in Yorkie, S74 and S97, are Atg1/ULK1 consensus target sites and are phosphorylated by ULK1 in vitro, thereby preventing its binding to Scalloped. In vivo, gain of function of Atg1, or its activator Acinus, caused elevated Yorkie phosphorylation and inhibited Yorkie's growth-promoting activity. Loss of function of Atg1 or Acinus raised expression of Yorkie target genes and increased tissue size. Unlike Atg1's role in autophagy, Atg1-mediated phosphorylation of Yorkie does not require Atg13. Atg1 is activated by starvation and other cellular stressors and therefore can impose temporary stress-induced constraints on the growth-promoting gene networks under the control of Hippo-Yorkie signaling.
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Affiliation(s)
- Lauren K Tyra
- Peter O'Donnell Jr. Brain Institute, Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390-9111, USA
| | - Nilay Nandi
- Peter O'Donnell Jr. Brain Institute, Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390-9111, USA
| | - Charles Tracy
- Peter O'Donnell Jr. Brain Institute, Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390-9111, USA
| | - Helmut Krämer
- Peter O'Donnell Jr. Brain Institute, Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390-9111, USA; Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390-9111, USA.
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45
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A Review of ULK1-Mediated Autophagy in Drug Resistance of Cancer. Cancers (Basel) 2020; 12:cancers12020352. [PMID: 32033142 PMCID: PMC7073181 DOI: 10.3390/cancers12020352] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 12/19/2022] Open
Abstract
The difficulty of early diagnosis and the development of drug resistance are two major barriers to the successful treatment of cancer. Autophagy plays a crucial role in several cellular functions, and its dysregulation is associated with both tumorigenesis and drug resistance. Unc-51-like kinase 1 (ULK1) is a serine/threonine kinase that participates in the initiation of autophagy. Many studies have indicated that compounds that directly or indirectly target ULK1 could be used for tumor therapy. However, reports of the therapeutic effects of these compounds have come to conflicting conclusions. In this work, we reviewed recent studies related to the effects of ULK1 on the regulation of autophagy and the development of drug resistance in cancers, with the aim of clarifying the mechanistic underpinnings of this therapeutic target.
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46
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Honda S, Arakawa S, Yamaguchi H, Torii S, Tajima Sakurai H, Tsujioka M, Murohashi M, Shimizu S. Association Between Atg5-independent Alternative Autophagy and Neurodegenerative Diseases. J Mol Biol 2020; 432:2622-2632. [PMID: 31978398 DOI: 10.1016/j.jmb.2020.01.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/08/2020] [Accepted: 01/11/2020] [Indexed: 12/19/2022]
Abstract
Autophagy is a cellular process that degrades intracellular components, including misfolded proteins and damaged organelles. Many neurodegenerative diseases are considered to progress via the accumulation of misfolded proteins and damaged organelles; therefore, autophagy functions in regulating disease severity. There are at least two types of autophagy (canonical autophagy and alternative autophagy), and canonical autophagy has been applied to therapeutic strategies against various types of neurodegenerative diseases. In contrast, the role of alternative autophagy has not yet been clarified, but it is speculated to be involved in the pathogenesis of various neurodegenerative diseases, including Alzheimer's disease.
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Affiliation(s)
- Shinya Honda
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Satoko Arakawa
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Hirofumi Yamaguchi
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Satoru Torii
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Hajime Tajima Sakurai
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Masatsune Tsujioka
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Michiko Murohashi
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shigeomi Shimizu
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
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47
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Khamrui S, Ung PMU, Secor C, Schlessinger A, Lazarus MB. High-Resolution Structure and Inhibition of the Schizophrenia-Linked Pseudokinase ULK4. J Am Chem Soc 2019; 142:33-37. [PMID: 31841327 DOI: 10.1021/jacs.9b10458] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The ULK (UNC51-like) enzymes are a family of mammalian kinases that have critical roles in autophagy and development. While ULK1, ULK2, and ULK3 have been characterized, very little is known about ULK4. However, recently, deletions in ULK4 have been genetically linked to increased susceptibility to developing schizophrenia, a devastating neuropsychiatric disease with high heritability but few genes identified. Interestingly, ULK4 is a pseudokinase with some unusual mutations in the kinase catalytic motifs. Here, we report the first structure of the human ULK4 kinase at high resolution and show that although ULK4 has no apparent phosphotransfer activity, it can strongly bind ATP. We find an unusual mechanism for binding ATP in a Mg2+-independent manner, including a rare hydrophobic bridge in the active site. In addition, we develop two assays for ATP binding to ULK4, perform a virtual and experimental screen to identify small-molecule binders of ULK4, and identify several novel scaffolds that bind ULK4 and can lead the way to more selective small molecules that may help shed light on the function of this enigmatic protein.
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Affiliation(s)
- Susmita Khamrui
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States
| | - Peter M U Ung
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States.,Department of Pharmacology , Yale University , New Haven , Connecticut 06510 , United States
| | - Cody Secor
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States
| | - Avner Schlessinger
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States
| | - Michael B Lazarus
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States
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48
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Improved Motor Nerve Regeneration by SIRT1/Hif1a-Mediated Autophagy. Cells 2019; 8:cells8111354. [PMID: 31671642 PMCID: PMC6912449 DOI: 10.3390/cells8111354] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 10/12/2019] [Accepted: 10/29/2019] [Indexed: 02/06/2023] Open
Abstract
Complete restoring of functional connectivity between neurons or target tissue after traumatic lesions is still an unmet medical need. Using models of nerve axotomy and compression, we investigated the effect of autophagy induction by genetic and pharmacological manipulation on motor nerve regeneration. ATG5 or NAD+-dependent deacetylase sirtuin-1 (SIRT1) overexpression on spinal motoneurons stimulates mTOR-independent autophagy and facilitates a growth-competent state improving motor axonal regeneration with better electromyographic records after nerve transection and suture. In agreement with this, using organotypic spinal cord cultures and the human cell line SH-SY5Y, we observed that the activation of SIRT1 and autophagy by NeuroHeal increased neurite outgrowth and length extension and that this was mediated by downstream HIF1a. To conclude, SIRT1/Hifα-dependent autophagy confers a more pro-regenerative phenotype to motoneurons after peripheral nerve injury. Altogether, we provide evidence showing that autophagy induction by SIRT1/Hifα activation or NeuroHeal treatment is a novel therapeutic option for improving motor nerve regeneration and functional recovery after injury.
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49
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Suomi F, McWilliams T. Autophagy in the mammalian nervous system: a primer for neuroscientists. Neuronal Signal 2019; 3:NS20180134. [PMID: 32269837 PMCID: PMC7104325 DOI: 10.1042/ns20180134] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 07/06/2019] [Accepted: 08/05/2019] [Indexed: 12/12/2022] Open
Abstract
Autophagy refers to the lysosomal degradation of damaged or superfluous components and is essential for metabolic plasticity and tissue integrity. This evolutionarily conserved process is particularly vital to mammalian post-mitotic cells such as neurons, which face unique logistical challenges and must sustain homoeostasis over decades. Defective autophagy has pathophysiological importance, especially for human neurodegeneration. The present-day definition of autophagy broadly encompasses two distinct yet related phenomena: non-selective and selective autophagy. In this minireview, we focus on established and emerging concepts in the field, paying particular attention to the physiological significance of macroautophagy and the burgeoning world of selective autophagy pathways in the context of the vertebrate nervous system. By highlighting established basics and recent breakthroughs, we aim to provide a useful conceptual framework for neuroscientists interested in autophagy, in addition to autophagy enthusiasts with an eye on the nervous system.
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Affiliation(s)
- Fumi Suomi
- Translational Stem Cell Biology and Metabolism Program, Research Programs Unit, Faculty of Medicine, Biomedicum Helsinki, University of Helsinki, Haartmaninkatu 8, Helsinki 00290, Finland
| | - Thomas G. McWilliams
- Translational Stem Cell Biology and Metabolism Program, Research Programs Unit, Faculty of Medicine, Biomedicum Helsinki, University of Helsinki, Haartmaninkatu 8, Helsinki 00290, Finland
- Department of Anatomy, Faculty of Medicine, Biomedicum Helsinki, University of Helsinki, Haartmaninkatu 8, Helsinki 00290, Finland
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50
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Lou G, Palikaras K, Lautrup S, Scheibye-Knudsen M, Tavernarakis N, Fang EF. Mitophagy and Neuroprotection. Trends Mol Med 2019; 26:8-20. [PMID: 31375365 DOI: 10.1016/j.molmed.2019.07.002] [Citation(s) in RCA: 255] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 06/25/2019] [Accepted: 07/03/2019] [Indexed: 12/13/2022]
Abstract
Neurodegenerative diseases are strongly age-related and currently cannot be cured, with a surge of patient numbers in the coming decades in view of the emerging worldwide ageing population, bringing healthcare and socioeconomic challenges. Effective therapies are urgently needed, and are dependent on new aetiological mechanisms. In neurons, efficient clearance of damaged mitochondria, through the highly evolutionary conserved cellular process termed mitophagy, plays a fundamental role in mitochondrial and metabolic homeostasis, energy supply, neuronal survival, and health. Conversely, defective mitophagy leads to accumulation of damaged mitochondria and cellular dysfunction, contributing to ageing and age-predisposed neurodegeneration. Here, we discuss the contribution of defective mitophagy in these diseases, and underlying molecular mechanisms, and highlight novel therapeutics based on new discovered mitophagy-inducing strategies.
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Affiliation(s)
- Guofeng Lou
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Konstantinos Palikaras
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Crete, Greece; Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, 70013, Crete, Greece
| | - Sofie Lautrup
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Morten Scheibye-Knudsen
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Crete, Greece; Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, 70013, Crete, Greece
| | - Evandro F Fang
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway.
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