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Liu W, Wang K, Lin Y, Wang L, Jin X, Qiu Y, Sun W, Zhang L, Sun Y, Dou X, Luo S, Su Y, Sun Q, Xiang W, Diao F, Li J. VPS34 Governs Oocyte Developmental Competence by Regulating Mito/Autophagy: A Novel Insight into the Significance of RAB7 Activity and Its Subcellular Location. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2308823. [PMID: 39287146 PMCID: PMC11538714 DOI: 10.1002/advs.202308823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 08/06/2024] [Indexed: 09/19/2024]
Abstract
Asynchronous nuclear and cytoplasmic maturation in human oocytes is believed to cause morphological anomalies after controlled ovarian hyperstimulation. Vacuolar protein sorting 34 (VPS34) is renowned for its pivotal role in regulating autophagy and endocytic trafficking. To investigate its impact on oocyte development, oocyte-specific knockout mice (ZcKO) are generated, and these mice are completely found infertile, with embryonic development halted at 2- to 4-cell stage. This infertility is related with a disruption on autophagic/mitophagic flux in ZcKO oocytes, leading to subsequent failure of zygotic genome activation (ZGA) in derived 2-cell embryos. The findings further elucidated the regulation of VPS34 on the activity and subcellular translocation of RAS-related GTP-binding protein 7 (RAB7), which is critical not only for the maturation of late endosomes and lysosomes, but also for initiating mitophagy via retrograde trafficking. VPS34 binds directly with RAB7 and facilitates its activity conversion through TBC1 domain family member 5 (TBC1D5). Consistent with the cytoplasmic vacuolation observed in ZcKO oocytes, defects in multiple vesicle trafficking systems are also identified in vacuolated human oocytes. Furthermore, activating VPS34 with corynoxin B (CB) treatment improved oocyte quality in aged mice. Hence, VPS34 activation may represent a novel approach to enhance oocyte quality in human artificial reproduction.
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Affiliation(s)
- Wenwen Liu
- State Key Laboratory of Reproductive Medicine and Offspring HealthWomen's Hospital of Nanjing Medical UniversityNanjing Maternity and Child Health Care HospitalNanjing Medical UniversityNanjingJiangsu211166China
| | - Kehan Wang
- State Key Laboratory of Reproductive Medicine and Offspring HealthCenter of Reproduction and GeneticsAffiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu SchoolNanjing Medical UniversitySuzhouJiangsu215002China
| | - Yuting Lin
- The Center for Clinical Reproductive MedicineState Key Laboratory of Reproductive Medicine and Offspring HealthThe First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu212028China
| | - Lu Wang
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
- Department of Reproductive MedicineCangzhou Central HospitalCangzhouHebei061012China
| | - Xin Jin
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
- Department of Center of Reproductive MedicineWuxi Maternity and Child Health Care HospitalNanjing Medical UniversityWuxiJiangsu214200China
| | - Yuexin Qiu
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
| | - Wenya Sun
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
| | - Ling Zhang
- Institute of Reproductive HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430074China
| | - Yan Sun
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
| | - Xiaowei Dou
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
- Department of Obstetrics and GynecologyThe Second Affiliated Hospital of Nanjing Medical UniversityNanjing Medical UniversityNanjingJiangsu210011China
| | - Shiming Luo
- Guangzhou Key Laboratory of Metabolic Diseases and Reproductive HealthGuangdong‐Hong Kong Metabolism & Reproduction Joint LaboratoryReproductive Medicine CenterGuangdong Second Provincial General HospitalGuangzhouGuangdong513023China
| | - Youqiang Su
- Shandong Provincial Key Laboratory of Animal Cells and Developmental BiologySchool of Life SciencesShandong UniversityQingdaoShandong266237China
| | - Qingyuan Sun
- Guangzhou Key Laboratory of Metabolic Diseases and Reproductive HealthGuangdong‐Hong Kong Metabolism & Reproduction Joint LaboratoryReproductive Medicine CenterGuangdong Second Provincial General HospitalGuangzhouGuangdong513023China
| | - Wenpei Xiang
- Institute of Reproductive HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430074China
| | - Feiyang Diao
- The Center for Clinical Reproductive MedicineState Key Laboratory of Reproductive Medicine and Offspring HealthThe First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu212028China
| | - Jing Li
- State Key Laboratory of Reproductive Medicine and Offspring HealthNanjing Medical UniversityNanjingJiangsu211166China
- Innovation Center of Suzhou Nanjing Medical UniversitySuzhou430074China
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Ren C, Carrillo ND, Cryns VL, Anderson RA, Chen M. Environmental pollutants and phosphoinositide signaling in autoimmunity. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133080. [PMID: 38091799 PMCID: PMC10923067 DOI: 10.1016/j.jhazmat.2023.133080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 02/08/2024]
Abstract
Environmental pollution stands as one of the most critical challenges affecting human health, with an estimated mortality rate linked to pollution-induced non-communicable diseases projected to range from 20% to 25%. These pollutants not only disrupt immune responses but can also trigger immunotoxicity. Phosphoinositide signaling, a pivotal regulator of immune responses, plays a central role in the development of autoimmune diseases and exhibits high sensitivity to environmental stressors. Among these stressors, environmental pollutants have become increasingly prevalent in our society, contributing to the initiation and exacerbation of autoimmune conditions. In this review, we summarize the intricate interplay between phosphoinositide signaling and autoimmune diseases within the context of environmental pollutants and contaminants. We provide an up-to-date overview of stress-induced phosphoinositide signaling, discuss 14 selected examples categorized into three groups of environmental pollutants and their connections to immune diseases, and shed light on the associated phosphoinositide signaling pathways. Through these discussions, this review advances our understanding of how phosphoinositide signaling influences the coordinated immune response to environmental stressors at a biological level. Furthermore, it offers valuable insights into potential research directions and therapeutic targets aimed at mitigating the impact of environmental pollutants on the pathogenesis of autoimmune diseases. SYNOPSIS: Phosphoinositide signaling at the intersection of environmental pollutants and autoimmunity provides novel insights for managing autoimmune diseases aggravated by pollutants.
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Affiliation(s)
- Chang Ren
- Department of Pharmacology, Joint Laboratory of Guangdong-Hong Kong Universities for Vascular Homeostasis and Diseases, School of Medicine, Southern University of Science and Technology, Shenzhen 518055, China
| | - Noah D Carrillo
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Vincent L Cryns
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA; University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Richard A Anderson
- University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Mo Chen
- Department of Pharmacology, Joint Laboratory of Guangdong-Hong Kong Universities for Vascular Homeostasis and Diseases, School of Medicine, Southern University of Science and Technology, Shenzhen 518055, China.
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Gui H, Tang WHW, Francke S, Li J, She R, Bazeley P, Pereira NL, Adams K, Luzum JA, Connolly TM, Hernandez AF, McNaughton CD, Williams LK, Lanfear DE. Common Variants on FGD5 Increase Hazard of Mortality or Rehospitalization in Patients With Heart Failure From the ASCEND-HF Trial. Circ Heart Fail 2023; 16:e010438. [PMID: 37725680 PMCID: PMC10597552 DOI: 10.1161/circheartfailure.122.010438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 06/13/2023] [Indexed: 09/21/2023]
Abstract
BACKGROUND Heart failure remains a global health burden, and patients hospitalized are particularly at risk, but genetic associates for subsequent death or rehospitalization are still lacking. METHODS The genetic substudy of the ASCEND-HF trial (Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure) was used to perform genome-wide association study and transethnic meta-analysis. The overall trial included the patients of self-reported European ancestry (n=2173) and African ancestry (n=507). The end point was death or heart failure rehospitalization within 180 days. Cox models adjusted for 11 a priori predictors of rehospitalization and 5 genetic principal components were used to test the association between single-nucleotide polymorphisms and outcome. Summary statistics from the 2 populations were combined via meta-analysis with the significance threshold considered P<5×10-8. RESULTS Common variants (rs2342882 and rs35850039 in complete linkage disequilibrium) located in FGD5 were significantly associated with the primary outcome in both ancestry groups (European Americans: hazard ratio [HR], 1.38; P=2.42×10-6; African ancestry: HR, 1.51; P=4.43×10-3; HR in meta-analysis, 1.41; P=4.25×10-8). FGD5 encodes a regulator of VEGF (vascular endothelial growth factor)-mediated angiogenesis, and in silico investigation revealed several previous genome-wide association study hits in this gene, among which rs748431 was associated with our outcome (HR, 1.20; meta P<0.01). Sensitivity analysis proved FGD5 common variants survival association did not appear to operate via coronary artery disease or nesiritide treatment (P>0.05); and the signal was still significant when changing the censoring time from 180 to 30 days (HR, 1.39; P=1.59×10-5). CONCLUSIONS In this multiethnic genome-wide association study of ASCEND-HF, single-nucleotide polymorphisms in FGD5 were associated with increased risk of death or rehospitalization. Additional investigation is required to examine biological mechanisms and whether FGD5 could be a therapeutic target. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier: NCT00475852.
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Affiliation(s)
- Hongsheng Gui
- Center for Individualized and Genomics Medicine Research (H.G., J.A.L., L.K.W., D.E.L.), Henry Ford Hospital, Detroit, MI
| | - W H Wilson Tang
- Department of Cardiovascular Medicine, Cleveland Clinic, OH (W.H.W.T., P.B.)
| | | | - Jia Li
- Department of Public Health Science (J.L., R.S.), Henry Ford Hospital, Detroit, MI
| | - Ruicong She
- Department of Public Health Science (J.L., R.S.), Henry Ford Hospital, Detroit, MI
| | - Peter Bazeley
- Department of Cardiovascular Medicine, Cleveland Clinic, OH (W.H.W.T., P.B.)
| | - Naveen L Pereira
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (N.L.P.)
| | - Kirkwood Adams
- Department of Medicine, University of North Carolina, Chapel Hill (K.A.)
| | - Jasmine A Luzum
- Center for Individualized and Genomics Medicine Research (H.G., J.A.L., L.K.W., D.E.L.), Henry Ford Hospital, Detroit, MI
- Department of Clinical Pharmacy, University of Michigan, Ann Arbor (J.A.L.)
| | - Thomas M Connolly
- Lansdale, PA, previously Janssen Research & Development LLC, Spring House, PA (T.M.C.)
| | | | - Candace D McNaughton
- Department of Emergency Medicine, Vanderbilt University Medical Center, Nashville, TN (C.D.M.)
| | - L Keoki Williams
- Center for Individualized and Genomics Medicine Research (H.G., J.A.L., L.K.W., D.E.L.), Henry Ford Hospital, Detroit, MI
| | - David E Lanfear
- Center for Individualized and Genomics Medicine Research (H.G., J.A.L., L.K.W., D.E.L.), Henry Ford Hospital, Detroit, MI
- Heart and Vascular Institute (D.E.L.), Henry Ford Hospital, Detroit, MI
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Powis G, Meuillet EJ, Indarte M, Booher G, Kirkpatrick L. Pleckstrin Homology [PH] domain, structure, mechanism, and contribution to human disease. Biomed Pharmacother 2023; 165:115024. [PMID: 37399719 DOI: 10.1016/j.biopha.2023.115024] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 06/14/2023] [Indexed: 07/05/2023] Open
Abstract
The pleckstrin homology [PH] domain is a structural fold found in more than 250 proteins making it the 11th most common domain in the human proteome. 25% of family members have more than one PH domain and some PH domains are split by one, or several other, protein domains although still folding to give functioning PH domains. We review mechanisms of PH domain activity, the role PH domain mutation plays in human disease including cancer, hyperproliferation, neurodegeneration, inflammation, and infection, and discuss pharmacotherapeutic approaches to regulate PH domain activity for the treatment of human disease. Almost half PH domain family members bind phosphatidylinositols [PIs] that attach the host protein to cell membranes where they interact with other membrane proteins to give signaling complexes or cytoskeleton scaffold platforms. A PH domain in its native state may fold over other protein domains thereby preventing substrate access to a catalytic site or binding with other proteins. The resulting autoinhibition can be released by PI binding to the PH domain, or by protein phosphorylation thus providing fine tuning of the cellular control of PH domain protein activity. For many years the PH domain was thought to be undruggable until high-resolution structures of human PH domains allowed structure-based design of novel inhibitors that selectively bind the PH domain. Allosteric inhibitors of the Akt1 PH domain have already been tested in cancer patients and for proteus syndrome, with several other PH domain inhibitors in preclinical development for treatment of other human diseases.
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Affiliation(s)
- Garth Powis
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA.
| | | | - Martin Indarte
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
| | - Garrett Booher
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
| | - Lynn Kirkpatrick
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
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Molitoris BA, Sandoval RM, Yadav SPS, Wagner MC. Albumin Uptake and Processing by the Proximal Tubule: Physiologic, Pathologic and Therapeutic Implications. Physiol Rev 2022; 102:1625-1667. [PMID: 35378997 PMCID: PMC9255719 DOI: 10.1152/physrev.00014.2021] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
For nearly 50 years the proximal tubule (PT) has been known to reabsorb, process, and either catabolize or transcytose albumin from the glomerular filtrate. Innovative techniques and approaches have provided insights into these processes. Several genetic diseases, nonselective PT cell defects, chronic kidney disease (CKD), and acute PT injury lead to significant albuminuria, reaching nephrotic range. Albumin is also known to stimulate PT injury cascades. Thus, the mechanisms of albumin reabsorption, catabolism, and transcytosis are being reexamined with the use of techniques that allow for novel molecular and cellular discoveries. Megalin, a scavenger receptor, cubilin, amnionless, and Dab2 form a nonselective multireceptor complex that mediates albumin binding and uptake and directs proteins for lysosomal degradation after endocytosis. Albumin transcytosis is mediated by a pH-dependent binding affinity to the neonatal Fc receptor (FcRn) in the endosomal compartments. This reclamation pathway rescues albumin from urinary losses and cellular catabolism, extending its serum half-life. Albumin that has been altered by oxidation, glycation, or carbamylation or because of other bound ligands that do not bind to FcRn traffics to the lysosome. This molecular sorting mechanism reclaims physiological albumin and eliminates potentially toxic albumin. The clinical importance of PT albumin metabolism has also increased as albumin is now being used to bind therapeutic agents to extend their half-life and minimize filtration and kidney injury. The purpose of this review is to update and integrate evolving information regarding the reabsorption and processing of albumin by proximal tubule cells including discussion of genetic disorders and therapeutic considerations.
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Affiliation(s)
- Bruce A. Molitoris
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Dept.of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Ruben M. Sandoval
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Shiv Pratap S. Yadav
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Mark C. Wagner
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States
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Zhang YF, Li Q, Huang PQ, Su T, Jiang SH, Hu LP, Zhang XL, Sun Y, Pan H, Yang XM, Li J, Gai YZ, Zhu L, Yao LL, Li DX, Sun YW, Zhang ZG, Liu DJ, Zhang YL, Nie HZ. A low amino acid environment promotes cell macropinocytosis through the YY1-FGD6 axis in Ras-mutant pancreatic ductal adenocarcinoma. Oncogene 2022; 41:1203-1215. [PMID: 35082383 DOI: 10.1038/s41388-021-02159-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 11/16/2021] [Accepted: 12/14/2021] [Indexed: 11/09/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC), cancer with a high mortality rate and the highest rate of KRAS mutation, reportedly internalizes proteins via macropinocytosis to adapt to low amino acid levels in the tumor microenvironment. Here, we aimed to identify a key regulator of macropinocytosis for the survival of tumor cells in a low amino acid environment in PDAC. FYVE, RhoGEF, and PH domain-containing protein 6 (FGD6) were identified as key regulators of macropinocytosis. FGD6 promoted PDAC cell proliferation, macropinocytosis, and tumor growth both in vitro and in vivo. The macropinocytosis level was decreased with FGD6 knockdown in PDAC cell lines. Moreover, FGD6 promoted macropinocytosis by participating in the trans-Golgi network and enhancing the membrane localization of growth factor receptors, especially the TGF-beta receptor. TGF-beta enhanced macropinocytosis in PDAC cells. Additionally, YAP nuclear translocation induced by a low amino acid tumor environment initiated FGD6 expression by coactivation with YY1. Clinical data analysis based on TCGA and GEO datasets showed that FGD6 expression was upregulated in PDAC tissue, and high FGD6 expression was correlated with poor prognosis in patients with PDAC. In tumor tissue from KrasG12D/+/Trp53R172H/-/Pdx1-Cre (KPC) mice, FGD6 expression escalated during PDAC development. Our results uncover a previously unappreciated mechanism of macropinocytosis in PDAC. Strategies to target FGD6 and growth factors membrane localization might be developed for the treatment of PDAC.
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Affiliation(s)
- Yi-Fan Zhang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Qing Li
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Pei-Qi Huang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Tong Su
- Department of Gynecology and Obstetrics, Shanghai Key Laboratory of Gynecology and Oncology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Shu-Heng Jiang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Li-Peng Hu
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xue-Li Zhang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yue Sun
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Hong Pan
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiao-Mei Yang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jun Li
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yan-Zhi Gai
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lei Zhu
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lin-Li Yao
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Dong-Xue Li
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yong-Wei Sun
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Zhi-Gang Zhang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - De-Jun Liu
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
| | - Yan-Li Zhang
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Hui-Zhen Nie
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Azad AK, Farhan MA, Murray CR, Suzuki K, Eitzen G, Touret N, Moore RB, Murray AG. FGD5 regulates endothelial cell PI3 kinase-β to promote neo-angiogenesis. FASEB J 2021; 36:e22080. [PMID: 34882832 DOI: 10.1096/fj.202100554r] [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: 03/31/2021] [Revised: 11/17/2021] [Accepted: 11/18/2021] [Indexed: 11/11/2022]
Abstract
Angiogenesis is required in embryonic development and tissue repair in the adult. Vascular endothelial growth factor (VEGF) initiates angiogenesis, and VEGF or its receptor is targeted therapeutically to block pathological angiogenesis. Additional pro-angiogenic cues, such as CXCL12 acting via the CXCR4 receptor, co-operate with VEGF/VEGFR2 to cue vascular patterning. We studied the role of FGD5, an endothelial Rho GTP/GDP exchange factor (RhoGEF), to regulate CXCR4-dependent signals in the endothelial cell (EC). Patient-derived renal cell carcinomas produce a complex milieu of growth factors that stimulated sprouting angiogenesis and endothelial tip cell differentiation ex vivo that was blocked by EC FGD5 loss. In a simplified model, CXCL12 augmented sprouting and tip gene expression under conditions where VEGF was limiting. CXCL12-stimulated tip cell differentiation was dependent on PI3 kinase (PI3K)-β activity. Knockdown of EC FGD5 abolished CXCR4 signaling to PI3K-β and Akt. Further, inhibition of Rac1, a Rho GTPase required for PI3K-β activity, recapitulated the signaling defects of FGD5 deficiency, suggesting that FGD5 may regulate PI3K-β activity through Rac1. Overexpression of a RhoGEF deficient, Dbl domain-deleted FGD5 mutant reduced CXCL12-stimulated Akt phosphorylation and failed to rescue PI3K signaling in native FGD5-deficient EC, indicating that FGD5 RhoGEF activity is required for FDG5 function. Endothelial expression of mutant PI3K-β with an inactivated Rho binding domain confirmed that CXCL12-stimulated PI3K activity in EC requires Rac1-GTP co-regulation. Together, this data identify the role of FGD5 to generate Rac1-GTP to regulate pro-angiogenic CXCR4-dependent PI3K-β signaling in EC. Inhibition of FGD5 activity may complement current angiogenesis inhibitor drugs.
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Affiliation(s)
- Abul K Azad
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Maikel A Farhan
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Cameron R Murray
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Kunimasa Suzuki
- Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Gary Eitzen
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Nicolas Touret
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Ronald B Moore
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada
| | - Allan G Murray
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
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Overduin M, Kervin TA. The phosphoinositide code is read by a plethora of protein domains. Expert Rev Proteomics 2021; 18:483-502. [PMID: 34351250 DOI: 10.1080/14789450.2021.1962302] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION The proteins that decipher nucleic acid- and protein-based information are well known, however, those that read membrane-encoded information remain understudied. Here we report 70 different human, microbial and viral protein folds that recognize phosphoinositides (PIs), comprising the readers of a vast membrane code. AREAS COVERED Membrane recognition is best understood for FYVE, PH and PX domains, which exemplify hundreds of PI code readers. Comparable lipid interaction mechanisms may be mediated by kinases, adjacent C1 and C2 domains, trafficking arrestin, GAT and VHS modules, membrane-perturbing annexin, BAR, CHMP, ENTH, HEAT, syntaxin and Tubby helical bundles, multipurpose FERM, EH, MATH, PHD, PDZ, PROPPIN, PTB and SH2 domains, as well as systems that regulate receptors, GTPases and actin filaments, transfer lipids and assembled bacterial and viral particles. EXPERT OPINION The elucidation of how membranes are recognized has extended the genetic code to the PI code. Novel discoveries include PIP-stop and MET-stop residues to which phosphates and metabolites are attached to block phosphatidylinositol phosphate (PIP) recognition, memteins as functional membrane protein apparatuses, and lipidons as lipid "codons" recognized by membrane readers. At least 5% of the human proteome senses such membrane signals and allows eukaryotic organelles and pathogens to operate and replicate.
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Affiliation(s)
- Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Troy A Kervin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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Kervin TA, Wiseman BC, Overduin M. Phosphoinositide Recognition Sites Are Blocked by Metabolite Attachment. Front Cell Dev Biol 2021; 9:690461. [PMID: 34368138 PMCID: PMC8340361 DOI: 10.3389/fcell.2021.690461] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/18/2021] [Indexed: 12/16/2022] Open
Abstract
Membrane readers take part in trafficking and signaling processes by localizing proteins to organelle surfaces and transducing molecular information. They accomplish this by engaging phosphoinositides (PIs), a class of lipid molecules which are found in different proportions in various cellular membranes. The prototypes are the PX domains, which exhibit a range of specificities for PIs. Our meta-analysis indicates that recognition of membranes by PX domains is specifically controlled by modification of lysine and arginine residues including acetylation, hydroxyisobutyrylation, glycation, malonylation, methylation and succinylation of sidechains that normally bind headgroups of phospholipids including organelle-specific PI signals. Such metabolite-modulated residues in lipid binding elements are named MET-stops here to highlight their roles as erasers of membrane reader functions. These modifications are concentrated in the membrane binding sites of half of all 49 PX domains in the human proteome and correlate with phosphoregulatory sites, as mapped using the Membrane Optimal Docking Area (MODA) algorithm. As these motifs are mutated and modified in various cancers and the responsible enzymes serve as potential drug targets, the discovery of MET-stops as a widespread inhibitory mechanism may aid in the development of diagnostics and therapeutics aimed at the readers, writers and erasers of the PI code.
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Affiliation(s)
- Troy A Kervin
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Brittany C Wiseman
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.,Molecular and Cellular Biology, MacEwan University, Edmonton, AB, Canada.,SMALP Network, Edmonton, AB, Canada
| | - Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.,SMALP Network, Edmonton, AB, Canada
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10
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Zeng J, Li M, Shi H, Guo J. Upregulation of FGD6 Predicts Poor Prognosis in Gastric Cancer. Front Med (Lausanne) 2021; 8:672595. [PMID: 34291059 PMCID: PMC8288026 DOI: 10.3389/fmed.2021.672595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 06/01/2021] [Indexed: 12/21/2022] Open
Abstract
Background: The aim of this study was to investigate the prognostic significance of faciogenital dysplasia 6 (FGD6) in gastric cancer (GC). Methods: The data of GC patients from The Cancer Genome Atlas (TCGA) database were used for the primary study. Then, our data were validated by the GEO database and RuiJin cohort. The relationship between the FGD6 level and various clinicopathological features was analyzed by logistic regression and univariate Cox regression. Multivariate Cox regression analysis was used to evaluate whether FGD6 was an independent prognostic factor for survival of patients with GC. The relationship between FGD6 and overall survival time was explored by the Kaplan–Meier method. In addition, gene set enrichment analysis (GSEA) was performed to investigate the possible biological processes of FGD6. Results: The FGD6 level was significantly overexpressed in GC tissues, compared with adjacent normal tissues. The high expression of FGD6 was related to a high histological grade, stage, and T classification and poor prognosis of GC. Multivariate Cox regression analysis showed that FGD6 was an independent prognostic factor for survival of patients with GC. GSEA identified that the high expression of FGD6 was mainly enriched in regulation of actin cytoskeleton. Conclusion: FGD6 may be a prognostic biomarker for predicting the outcome of patients with GC.
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Affiliation(s)
- Jianmin Zeng
- The Affiliated Hospital of Kunming University of Science and Technology, The First People's Hospital of Yunnan Province, Kunming, China
| | - Man Li
- The First Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Huasheng Shi
- Medical College, Qingdao University, Qingdao, China
| | - Jianhui Guo
- Second Department of General Surgery, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology, Kunming, China
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11
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Watanabe N, Nakada-Tsukui K, Nozaki T. Diversity of phosphoinositide binding proteins in Entamoeba histolytica. Parasitol Int 2021; 83:102367. [PMID: 33905816 DOI: 10.1016/j.parint.2021.102367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/26/2021] [Accepted: 04/05/2021] [Indexed: 12/26/2022]
Abstract
Phosphatidylinositol phosphates (PIPs, phosphoinositides) are localized to the membranes of all cellular compartments, and play pivotal roles in multiple cellular events. To fulfill their functions, PIPs that are located to specific organelles or membrane domains bind to and recruit various proteins in spatiotemporal specific manner via protein domains that selectively bind to either a single or an array of PIPs. In Entamoeba histolytica, the human intestinal protozoan parasite, PIPs and PIP-binding proteins have been shown to be involved in their virulence-associated mechanisms such as cell motility, vesicular traffic, trogo- and phagocytosis. In silico search of the domains and the signatures implicated in PIP binding in the E. histolytica proteome allows identification of dozens of potential PIP-binding proteins. However, such analysis is often misleading unless the protein domain used as query is cautiously selected and the binding specificity of the proteins are experimentally validated. This is because all the domains initially presumed to bind PIPs in other systems are not always capable of PIP binding, but rather involved in other biological roles. In this review, we carried out in silico survey of proteins which have PIP-binding domains in the E. histolytica genome by utilizing only validated PIP-binding domains that had been experimentally proven to be faithful PIP-binding bioprobes. Our survey has identified that FYVE (Fab1, YOTB1, Vac1, EEA1) and PH (pleckstrin homology) domain containing proteins are the most expanded families in E. histolytica. A few FYVE domain-containing proteins (EhFP4 and 10) and phox homology (PX) domain containing proteins (EhSNX1 and 2) were previously studied in depth in E. histolytica. Furthermore, most of the identified PH domain-containing proteins are annotated as protein kinases and possess protein kinase domains. Overall, PIP-binding domain-containing proteins that can be identified by in silico survey of the genome using the domains from well characterized bioprobes are limited in E. histolytica. However, their domain architectures are often unique, suggesting unique evolution of PIP-binding domain-containing proteins in this organism.
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Affiliation(s)
- Natsuki Watanabe
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
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12
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Park S, Guo Y, Negre J, Preto J, Smithers CC, Azad AK, Overduin M, Murray AG, Eitzen G. Fgd5 is a Rac1-specific Rho GEF that is selectively inhibited by aurintricarboxylic acid. Small GTPases 2021; 12:147-160. [PMID: 31601145 PMCID: PMC7849785 DOI: 10.1080/21541248.2019.1674765] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 09/14/2019] [Accepted: 09/25/2019] [Indexed: 02/07/2023] Open
Abstract
Rho proteins are signalling molecules that control cellular dynamics, movement and morphological changes. They are activated by Rho guanine-nucleotide exchange factors (Rho GEFs) that transduce upstream signals into Rho-mediated activation of downstream processes. Fgd5 is a Rho GEF involved in angiogenesis and its target Rho protein for this process has been linked to Cdc42 activation. Here, we examined the function of purified Fgd5, specifically, which Rho proteins it activates and pinpoint the structural domains required for enzymatic activity. Using a GEF enzyme assay, we found that purified Fgd5 showed preferential activation of Rac1 and direct binding of Rac1 in pull-down and co-immunoprecipitation assays. Structural comparisons showed that the Fgd5 DH domain is highly similar to the Rac1 GEF, TrioN, supporting a role for Fgd5 as a Rac1 GEF. Compounds that bind to purified Fgd5 DH-PH protein were identified by screening a small molecule library via surface plasmon resonance. The effects of eleven ligands were further examined for their ability to inhibit the Fgd5 GEF enzymatic activity and Rac1 interaction. From these studies, we found that the compound aurintricarboxylic acid, and to a lesser extent mitoxantrone dihydrochloride, inhibited both Fgd5 GEF activation of Rac1 and their interaction. Aurintricarboxylic acid had no effect on the activity or binding of the Rac1 GEF, TrioN, thus demonstrating the feasibility of selectively disrupting Rho GEF activators. Abbreviations: a.a.: amino acid; ATA: aurintricarboxylic acid; DH: Dbl homology; DOCK: dictator of cytokinesis; Fgd: faciogenital dysplasia; GEF: guanine-nucleotide exchange factor; GST: glutathione S-transferase; LOPAC: library of pharmacologically active compounds; PH: pleckstrin homology; PDB: protein data bank; s.e.m.: standard error of the mean; SPR: surface plasmon resonance.
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Affiliation(s)
- Sally Park
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Yitian Guo
- Department of Medicine-Division of Pulmonary Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Judeah Negre
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Jordane Preto
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Cameron C. Smithers
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Abul Kalam Azad
- Department of Medicine, Division of Nephrology, University of Alberta, Edmonton, Alberta, Canada
| | - Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Allan G. Murray
- Department of Medicine, Division of Nephrology, University of Alberta, Edmonton, Alberta, Canada
| | - Gary Eitzen
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine-Division of Pulmonary Medicine, University of Alberta, Edmonton, Alberta, Canada
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13
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EPEC Recruits a Cdc42-Specific GEF, Frabin, To Facilitate PAK Activation and Host Cell Colonization. mBio 2020; 11:mBio.01423-20. [PMID: 33144373 PMCID: PMC7642674 DOI: 10.1128/mbio.01423-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) is a leading cause of diarrhea in children, especially in the developing world. EPEC initiates infection by attaching to cells in the host intestine, triggering the formation of actin-rich “pedestal” structures directly beneath the adherent pathogen. These bacteria inject their own receptor into host cells, which upon binding to a protein on the pathogen surface triggers pedestal formation. Multiple other proteins are also delivered into the cells of the host intestine, which work together to hijack host signaling pathways to drive pedestal production. Here we show how EPEC hijacks a host protein, Frabin, which creates the conditions in the cell necessary for the pathogen to manipulate a specific pathway that promotes pedestal formation. This provides new insights into this essential early stage in disease caused by EPEC. Enteropathogenic Escherichia coli (EPEC) is an extracellular pathogen that tightly adheres to host cells by forming “actin pedestals” beneath the bacteria, a critical step in pathogenesis. EPEC injects effector proteins that manipulate host cell signaling cascades to trigger pedestal assembly. We have recently shown that one such effector, EspG, hijacks p21-activated kinase (PAK) and sustains its activated state to drive the cytoskeletal changes necessary for attachment of the pathogen to target cells. This EspG subversion of PAK required active Rho family small GTPases in the host cell. Here we show that EPEC itself promotes the activation of Rho GTPases by recruiting Frabin, a host guanine nucleotide exchange factor (GEF) for the Rho GTPase Cdc42. Cells devoid of Frabin showed significantly lower EPEC-induced PAK activation, pedestal formation, and bacterial attachment. Frabin recruitment to sites of EPEC attachment was driven by EspG and required localized enrichment of phosphatidylinositol 4,5-bisphosphate (PIP2) and host Arf6. Our findings identify Frabin as a key target for EPEC to ensure the activation status of cellular GTPases required for actin pedestal formation.
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14
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Buechner M, Yang Z, Al-Hashimi H. A Series of Tubes: The C. elegans Excretory Canal Cell as a Model for Tubule Development. J Dev Biol 2020; 8:jdb8030017. [PMID: 32906663 PMCID: PMC7557474 DOI: 10.3390/jdb8030017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 08/31/2020] [Accepted: 09/02/2020] [Indexed: 12/25/2022] Open
Abstract
Formation and regulation of properly sized epithelial tubes is essential for multicellular life. The excretory canal cell of C. elegans provides a powerful model for investigating the integration of the cytoskeleton, intracellular transport, and organismal physiology to regulate the developmental processes of tube extension, lumen formation, and lumen diameter regulation in a narrow single cell. Multiple studies have provided new understanding of actin and intermediate filament cytoskeletal elements, vesicle transport, and the role of vacuolar ATPase in determining tube size. Most of the genes discovered have clear homologues in humans, with implications for understanding these processes in mammalian tissues such as Schwann cells, renal tubules, and brain vasculature. The results of several new genetic screens are described that provide a host of new targets for future studies in this informative structure.
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Affiliation(s)
- Matthew Buechner
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA;
- Correspondence:
| | - Zhe Yang
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA;
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15
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Characterization of guanine nucleotide exchange activity of DH domain of human FGD2. Protein Expr Purif 2020; 176:105693. [PMID: 32681954 DOI: 10.1016/j.pep.2020.105693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/10/2020] [Accepted: 06/24/2020] [Indexed: 11/21/2022]
Abstract
FGD2, a member of FGD family, contains a Dbl homology domain (DH) and two pleckstrin homology domains segregated by a FYVE domain. The DH domain has been deduced to be responsible for guanine nucleotide exchange of CDC42 to activate downstream factors. Our aim was to build a prokaryotic expression system for the DH domain and to examine its guanine nucleotide exchange activity toward CDC42 in vitro. A recombinant vector, which was successfully constructed based on pGEX-6P-1, was employed to express the DH domain of human FGD2 (FGD2-DH) in E. coli BL21 (DE3). Purified FGD2-DH behaved as a homogeneous monomer with an estimated molecular weight that corresponded to the theoretical molecular weight and was predicted to be an α-helix protein by circular dichroism spectroscopy. FGD2-DH displayed weak guanine nucleotide exchange activity in vitro and very weak interactions with CDC42 following glutaraldehyde cross-linking.
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16
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Maldonado MDM, Medina JI, Velazquez L, Dharmawardhane S. Targeting Rac and Cdc42 GEFs in Metastatic Cancer. Front Cell Dev Biol 2020; 8:201. [PMID: 32322580 PMCID: PMC7156542 DOI: 10.3389/fcell.2020.00201] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 03/09/2020] [Indexed: 12/20/2022] Open
Abstract
The Rho family GTPases Rho, Rac, and Cdc42 have emerged as key players in cancer metastasis, due to their essential roles in regulating cell division and actin cytoskeletal rearrangements; and thus, cell growth, migration/invasion, polarity, and adhesion. This review will focus on the close homologs Rac and Cdc42, which have been established as drivers of metastasis and therapy resistance in multiple cancer types. Rac and Cdc42 are often dysregulated in cancer due to hyperactivation by guanine nucleotide exchange factors (GEFs), belonging to both the diffuse B-cell lymphoma (Dbl) and dedicator of cytokinesis (DOCK) families. Rac/Cdc42 GEFs are activated by a myriad of oncogenic cell surface receptors, such as growth factor receptors, G-protein coupled receptors, cytokine receptors, and integrins; consequently, a number of Rac/Cdc42 GEFs have been implicated in metastatic cancer. Hence, inhibiting GEF-mediated Rac/Cdc42 activation represents a promising strategy for targeted metastatic cancer therapy. Herein, we focus on the role of oncogenic Rac/Cdc42 GEFs and discuss the recent advancements in the development of Rac and Cdc42 GEF-interacting inhibitors as targeted therapy for metastatic cancer, as well as their potential for overcoming cancer therapy resistance.
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Affiliation(s)
- Maria Del Mar Maldonado
- Department of Biochemistry, School of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
| | - Julia Isabel Medina
- Department of Biochemistry, School of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
| | - Luis Velazquez
- Department of Biochemistry, School of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
| | - Suranganie Dharmawardhane
- Department of Biochemistry, School of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
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17
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The C-terminal acidic motif of Phafin2 inhibits PH domain binding to phosphatidylinositol 3-phosphate. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183230. [PMID: 32126233 DOI: 10.1016/j.bbamem.2020.183230] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/15/2020] [Accepted: 02/18/2020] [Indexed: 02/07/2023]
Abstract
Changes in membrane curvature are required to control the function of subcellular compartments; malfunctions of such processes are associated with a wide range of human diseases. Membrane remodeling often depends upon the presence of phosphoinositides, which recruit protein effectors for a variety of cellular functions. Phafin2 is a phosphatidylinositol 3-phosphate (PtdIns3P)-binding effector involved in endosomal and lysosomal membrane-associated signaling. Both the Phafin2 PH and the FYVE domains bind PtdIns3P, although their redundant function in the protein is unclear. Through a combination of lipid-binding assays, we found that, unlike the FYVE domain, recognition of the PH domain to PtdIns3P requires a lipid bilayer. Using site-directed mutagenesis and truncation constructs, we discovered that the Phafin2 FYVE domain is constitutive for PtdIns3P binding, whereas PH domain binding to PtdIns3P is autoinhibited by a conserved C-terminal acidic motif. These findings suggest that binding of the Phafin2 PH domain to PtdIns3P in membrane compartments occurs through a highly regulated mechanism. Potential mechanisms are discussed throughout this report.
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18
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Ma C, Li H, Li X, Lu S, He J. The prognostic value of faciogenital dysplasias as biomarkers in head and neck squamous cell carcinoma. Biomark Med 2019; 13:1399-1415. [DOI: 10.2217/bmm-2019-0273] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aim: This present study aims to investigate the prognostic value of FGD genes for predicting the overall survival in head and neck squamous cell carcinoma (HNSC) patients. Materials & methods: Clinical information and FGD gene expressions of 513 HNSC patients were obtained from The Cancer Genome Atlas dataset. Kaplan–Meier survival, Pearson correlation coefficient analyses and enrichment analyses were performed based on The Cancer Genome Atlas dataset, as well as FGD gene expressions analysis in normal tissues. Results: The survival analyses showed that high levels of FGD2 and FGD3 mRNA expressions, and the combination of high levels of FGD2 and FGD3 mRNAs were associated with the favorable overall survival in HNSC patients (p < 0.01). Oppositely, no significant correlations (p > 0.05) were observed between gender and race and OS. Conclusion: Our findings suggest that the expression levels of FGD2 and FGD3 mRNAs in HNSC are associated with favorable prognosis and may be regarded as potential prognostic biomarkers.
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Affiliation(s)
- Chao Ma
- Department of Ophthalmology, the First Affiliated Hospital of Guangxi Medical University, 6 Shuangyong Rd. Nanning 530021 Guangxi Zhuang Autonomous Region, PR China
| | - Haoyu Li
- Graduate School, Guangxi University of Chinese Medicine, 179 Mingxiudong Rd. Nanning 530001 Guangxi Zhuang Autonomous Region, PR China
| | - Xian Li
- Faculty of Biology, Medicine & Health, University of Manchester, University of Manchester, Oxford Road, Manchester, Manchester, UK
| | - Shuwen Lu
- Department of Ophthalmology, the First Affiliated Hospital of Henan University of Chinese Medicine, 19 Renmin road, Zhengzhou, Henan Province, PR China
| | - Jianfeng He
- Department of Ophthalmology, the First Affiliated Hospital of Guangxi Medical University, 6 Shuangyong Rd. Nanning 530021 Guangxi Zhuang Autonomous Region, PR China
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