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Yao R, Shen J. Chaperone-mediated autophagy: Molecular mechanisms, biological functions, and diseases. MedComm (Beijing) 2023; 4:e347. [PMID: 37655052 PMCID: PMC10466100 DOI: 10.1002/mco2.347] [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: 12/15/2022] [Revised: 07/23/2023] [Accepted: 07/27/2023] [Indexed: 09/02/2023] Open
Abstract
Chaperone-mediated autophagy (CMA) is a lysosomal degradation pathway that eliminates substrate proteins through heat-shock cognate protein 70 recognition and lysosome-associated membrane protein type 2A-assisted translocation. It is distinct from macroautophagy and microautophagy. In recent years, the regulatory mechanisms of CMA have been gradually enriched, including the newly discovered NRF2 and p38-TFEB signaling, as positive and negative regulatory pathways of CMA, respectively. Normal CMA activity is involved in the regulation of metabolism, aging, immunity, cell cycle, and other physiological processes, while CMA dysfunction may be involved in the occurrence of neurodegenerative disorders, tumors, intestinal disorders, atherosclerosis, and so on, which provides potential targets for the treatment and prediction of related diseases. This article describes the general process of CMA and its role in physiological activities and summarizes the connection between CMA and macroautophagy. In addition, human diseases that concern the dysfunction or protective role of CMA are discussed. Our review deepens the understanding of the mechanisms and physiological functions of CMA and provides a summary of past CMA research and a vision of future directions.
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Affiliation(s)
- Ruchen Yao
- Division of Gastroenterology and HepatologyKey Laboratory of Gastroenterology and HepatologyMinistry of Health, Inflammatory Bowel Disease Research CenterShanghaiChina
- Renji Hospital, School of MedicineShanghai Jiao Tong UniversityShanghaiChina
- Shanghai Institute of Digestive DiseaseShanghaiChina
| | - Jun Shen
- Division of Gastroenterology and HepatologyKey Laboratory of Gastroenterology and HepatologyMinistry of Health, Inflammatory Bowel Disease Research CenterShanghaiChina
- Renji Hospital, School of MedicineShanghai Jiao Tong UniversityShanghaiChina
- Shanghai Institute of Digestive DiseaseShanghaiChina
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2
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Nakano M, Imamura R, Sugi T, Nishimura M. Human FAM3C restores memory-based thermotaxis of Caenorhabditis elegans famp-1/m70.4 loss-of-function mutants. PNAS NEXUS 2022; 1:pgac242. [PMID: 36712359 PMCID: PMC9802357 DOI: 10.1093/pnasnexus/pgac242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 10/21/2022] [Indexed: 06/18/2023]
Abstract
The family with sequence similarity 3 (FAM3) superfamily represents a distinct class of signaling molecules that share a characteristic structural feature. Mammalian FAM3 member C (FAM3C) is abundantly expressed in neuronal cells and released from the synaptic vesicle to the extracellular milieu in an activity-dependent manner. However, the neural function of FAM3C has yet to be fully clarified. We found that the protein sequence of human FAM3C is similar to that of the N-terminal tandem domains of Caenorhabditis elegans FAMP-1 (formerly named M70.4), which has been recognized as a tentative ortholog of mammalian FAM3 members or protein-O-mannose β-1,2-N-acetylglucosaminyltransferase 1 (POMGnT1). Missense mutations in the N-terminal domain, named Fam3L2, caused defects in memory-based thermotaxis but not in chemotaxis behaviors; these defects could be restored by AFD neuron-specific exogenous expression of a polypeptide corresponding to the Fam3L2 domain but not that corresponding to the Fam3L1. Moreover, human FAM3C could also rescue defective thermotaxis behavior in famp-1 mutant worms. An in vitro assay revealed that the Fam3L2 and FAM3C can bind with carbohydrates, similar to the stem domain of POMGnT1. The athermotactic mutations in the Fam3L2 domain caused a partial loss-of-function of FAMP-1, whereas the C-terminal truncation mutations led to more severe neural dysfunction that reduced locomotor activity. Overall, we show that the Fam3L2 domain-dependent function of FAMP-1 in AFD neurons is required for the thermotaxis migration of C. elegans and that human FAM3C can act as a substitute for the Fam3L2 domain in thermotaxis behaviors.
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Affiliation(s)
- Masaki Nakano
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta-Tsukinowa, Otsu, Shiga 520-2192, Japan
| | - Ryuki Imamura
- Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, 3-10-23 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan
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Kim SS, Lee EH, Shin JH, Seo SR. MAP kinase/ERK kinase 1 (MEK1) phosphorylates regulator of calcineurin 1 (RCAN1) to regulate neuronal differentiation. J Cell Physiol 2021; 237:1406-1417. [PMID: 34647615 DOI: 10.1002/jcp.30609] [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: 05/25/2021] [Revised: 09/27/2021] [Accepted: 10/04/2021] [Indexed: 11/08/2022]
Abstract
Regulator of calcineurin 1 (RCAN1) is located close to the Down syndrome critical region (DSCR) on human chromosome 21 and is related to the Down syndrome (DS) phenotype. To identify a novel binding partner of RCAN1, we performed yeast two-hybrid screening and identified mitogen-activated protein (MAP) kinase/extracellular signal-regulated kinase (ERK) kinase 1 (MEK1) as a partner. MEK1 was able to bind and phosphorylate RCAN1 in vitro and in vivo. MEK1-dependent RCAN1 phosphorylation caused an increase in RCAN1 expression by increasing the protein half-life. Nerve growth factor (NGF)-dependent activation of the MEK1 pathway consistently induced RCAN1 expression. Moreover, we found that RCAN1 overexpression inhibited NGF-induced neurite outgrowth and expression of neuronal marker genes, such as growth cone-associated protein 43 (GAP43) and synapsin I, via inhibition of MEK1-ERK1/2 pathways. Our findings provide evidence that MEK1-dependent RCAN1 phosphorylation acts as an important molecular mechanism in the control of neuronal differentiation.
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Affiliation(s)
- Seon Sook Kim
- Department of Molecular Bioscience, Kangwon National University, Chuncheon, Republic of Korea
| | - Eun Hye Lee
- Department of Molecular Bioscience, Kangwon National University, Chuncheon, Republic of Korea
| | - Jin Hak Shin
- Department of Molecular Bioscience, Kangwon National University, Chuncheon, Republic of Korea
| | - Su Ryeon Seo
- Department of Molecular Bioscience, Kangwon National University, Chuncheon, Republic of Korea
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4
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Cho JY, Choi TW, Kim SH, Ahnn J, Lee SK. Morphological Characterization of small, dumpy, and long Phenotypes in Caenorhabditis elegans. Mol Cells 2021; 44:160-167. [PMID: 33692220 PMCID: PMC8019597 DOI: 10.14348/molcells.2021.2236] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/18/2021] [Accepted: 02/22/2021] [Indexed: 11/27/2022] Open
Abstract
The determinant factors of an organism's size during animal development have been explored from various angles but remain partially understood. In Caenorhabditis elegans, many genes affecting cuticle structure, cell growth, and proliferation have been identified to regulate the worm's overall morphology, including body size. While various mutations in those genes directly result in changes in the morphological phenotypes, there is still a need for established, clear, and distinct standards to determine the apparent abnormality in a worm's size and shape. In this study, we measured the body length, body width, terminal bulb length, and head size of mutant worms with reported Dumpy (Dpy), Small (Sma) or Long (Lon) phenotypes by plotting and comparing their respective ratios of various parameters. These results show that the Sma phenotypes are proportionally smaller overall with mild stoutness, and Dpy phenotypes are significantly stouter and have disproportionally small head size. This study provides a standard platform for determining morphological phenotypes designating and annotating mutants that exhibit body shape variations, defining the morphological phenotype of previously unexamined mutants.
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Affiliation(s)
- Joshua Young Cho
- Department of Life Science, School of Natural Sciences, Hanyang University, Seoul 04763, Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Korea
- Present address: Doctor of Dental Surgery Program, University of the Pacific, Arthur A. Dugoni School of Dentistry, San Francisco, CA 94103, USA
| | - Tae-Woo Choi
- Department of Life Science, School of Natural Sciences, Hanyang University, Seoul 04763, Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Korea
- Present address: Macrogen Inc., Seoul 08511, Korea
| | - Seung Hyun Kim
- Department of Life Science, School of Natural Sciences, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Korea
| | - Joohong Ahnn
- Department of Life Science, School of Natural Sciences, Hanyang University, Seoul 04763, Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Korea
| | - Sun-Kyung Lee
- Department of Life Science, School of Natural Sciences, Hanyang University, Seoul 04763, Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Korea
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Moyer AJ, Gardiner K, Reeves RH. All Creatures Great and Small: New Approaches for Understanding Down Syndrome Genetics. Trends Genet 2020; 37:444-459. [PMID: 33097276 DOI: 10.1016/j.tig.2020.09.017] [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: 08/07/2020] [Revised: 09/17/2020] [Accepted: 09/22/2020] [Indexed: 12/26/2022]
Abstract
Human chromosome 21 (Hsa21) contains more than 500 genes, making trisomy 21 one of the most complex genetic perturbations compatible with life. The ultimate goal of Down syndrome (DS) research is to design therapies that improve quality of life for individuals with DS by understanding which subsets of Hsa21 genes contribute to DS-associated phenotypes throughout the lifetime. However, the complexity of DS pathogenesis has made developing appropriate animal models an ongoing challenge. Here, we examine lessons learned from a variety of model systems, including yeast, nematode, fruit fly, and zebrafish, and discuss emerging methods for creating murine models that better reflect the genetic basis of trisomy 21.
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Affiliation(s)
- Anna J Moyer
- Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA; Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Katheleen Gardiner
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA (retired)
| | - Roger H Reeves
- Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA; Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
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Lee SK, Ahnn J. Regulator of Calcineurin (RCAN): Beyond Down Syndrome Critical Region. Mol Cells 2020; 43:671-685. [PMID: 32576715 PMCID: PMC7468584 DOI: 10.14348/molcells.2020.0060] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/23/2020] [Accepted: 05/25/2020] [Indexed: 12/19/2022] Open
Abstract
The regulator of calcineurin (RCAN) was first reported as a novel gene called DSCR1, encoded in a region termed the Down syndrome critical region (DSCR) of human chromosome 21. Genome sequence comparisons across species using bioinformatics revealed three members of the RCAN gene family, RCAN1, RCAN2, and RCAN3, present in most jawed vertebrates, with one member observed in most invertebrates and fungi. RCAN is most highly expressed in brain and striated muscles, but expression has been reported in many other tissues, as well, including the heart and kidneys. Expression levels of RCAN homologs are responsive to external stressors such as reactive oxygen species, Ca2+, amyloid β, and hormonal changes and upregulated in pathological conditions, including Alzheimer's disease, cardiac hypertrophy, diabetes, and degenerative neuropathy. RCAN binding to calcineurin, a Ca2+/calmodulin-dependent phosphatase, inhibits calcineurin activity, thereby regulating different physiological events via dephosphorylation of important substrates. Novel functions of RCANs have recently emerged, indicating involvement in mitochondria homeostasis, RNA binding, circadian rhythms, obesity, and thermogenesis, some of which are calcineurin-independent. These developments suggest that besides significant contributions to DS pathologies and calcineurin regulation, RCAN is an important participant across physiological systems, suggesting it as a favorable therapeutic target.
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Affiliation(s)
- Sun-Kyung Lee
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
| | - Joohong Ahnn
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
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Zhao Y, Long L, Wan J, Biliya S, Brady SC, Lee D, Ojemakinde A, Andersen EC, Vannberg FO, Lu H, McGrath PT. A spontaneous complex structural variant in rcan-1 increases exploratory behavior and laboratory fitness of Caenorhabditis elegans. PLoS Genet 2020; 16:e1008606. [PMID: 32092052 PMCID: PMC7058356 DOI: 10.1371/journal.pgen.1008606] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 03/05/2020] [Accepted: 01/11/2020] [Indexed: 01/02/2023] Open
Abstract
Over long evolutionary timescales, major changes to the copy number, function, and genomic organization of genes occur, however, our understanding of the individual mutational events responsible for these changes is lacking. In this report, we study the genetic basis of adaptation of two strains of C. elegans to laboratory food sources using competition experiments on a panel of 89 recombinant inbred lines (RIL). Unexpectedly, we identified a single RIL with higher relative fitness than either of the parental strains. This strain also displayed a novel behavioral phenotype, resulting in higher propensity to explore bacterial lawns. Using bulk-segregant analysis and short-read resequencing of this RIL, we mapped the change in exploration behavior to a spontaneous, complex rearrangement of the rcan-1 gene that occurred during construction of the RIL panel. We resolved this rearrangement into five unique tandem inversion/duplications using Oxford Nanopore long-read sequencing. rcan-1 encodes an ortholog to human RCAN1/DSCR1 calcipressin gene, which has been implicated as a causal gene for Down syndrome. The genomic rearrangement in rcan-1 creates two complete and two truncated versions of the rcan-1 coding region, with a variety of modified 5’ and 3’ non-coding regions. While most copy-number variations (CNVs) are thought to act by increasing expression of duplicated genes, these changes to rcan-1 ultimately result in the reduction of its whole-body expression due to changes in the upstream regions. By backcrossing this rearrangement into a common genetic background to create a near isogenic line (NIL), we demonstrate that both the competitive advantage and exploration behavioral changes are linked to this complex genetic variant. This NIL strain does not phenocopy a strain containing an rcan-1 loss-of-function allele, which suggests that the residual expression of rcan-1 is necessary for its fitness effects. Our results demonstrate how colonization of new environments, such as those encountered in the laboratory, can create evolutionary pressure to modify gene function. This evolutionary mismatch can be resolved by an unexpectedly complex genetic change that simultaneously duplicates and diversifies a gene into two uniquely regulated genes. Our work shows how complex rearrangements can act to modify gene expression in ways besides increased gene dosage. Evolution acts on genetic variants that modify phenotypes that increase the likelihood of staying alive and passing on these genetic changes to subsequent generations (i.e. fitness). There is general interest in understanding the types of genetic variants that can increase fitness in specific environments. One route that fitness can be increased is through changes in behavior, such as finding new food sources. Here, we identify a spontaneous genetic change that increases exploration behavior and fitness of animals in laboratory environments. Interestingly, this genetic change is not a simple genetic change that deletes or changes the sequence of a protein product, but rather a complex structural variant that simultaneously duplicates the rcan-1 gene and also modifies its expression in a number of tissues. Our work demonstrates how a complex structural change can duplicate a gene, modify the DNA control regions that determine its cellular sites of action, and confer a fitness advantage that could lead to its spread in a population.
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Affiliation(s)
- Yuehui Zhao
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Lijiang Long
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Interdisciplinary Graduate Program in Quantitative Biosciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Jason Wan
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States of America
| | - Shweta Biliya
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Shannon C. Brady
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America
| | - Daehan Lee
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America
| | - Akinade Ojemakinde
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Erik C. Andersen
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America
| | - Fredrik O. Vannberg
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Hang Lu
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Patrick T. McGrath
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Interdisciplinary Graduate Program in Quantitative Biosciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- * E-mail:
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8
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Kumarasamy S, Solanki S, Atolagbe OT, Joe B, Birnbaumer L, Vazquez G. Deep Transcriptomic Profiling of M1 Macrophages Lacking Trpc3. Sci Rep 2017; 7:39867. [PMID: 28051144 PMCID: PMC5209678 DOI: 10.1038/srep39867] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 11/28/2016] [Indexed: 01/18/2023] Open
Abstract
In previous studies using mice with macrophage-specific loss of TRPC3 we found a significant, selective effect of TRPC3 on the biology of M1, or inflammatory macrophages. Whereas activation of some components of the unfolded protein response and the pro-apoptotic mediators CamkII and Stat1 was impaired in Trpc3-deficient M1 cells, gathering insight about other molecular signatures within macrophages that might be affected by Trpc3 expression requires an alternative approach. In the present study we conducted RNA-seq analysis to interrogate the transcriptome of M1 macrophages derived from mice with macrophage-specific loss of TRPC3 and their littermate controls. We identified 160 significantly differentially expressed genes between the two groups, of which 62 were upregulated and 98 downregulated in control vs. Trpc3-deficient M1 macrophages. Gene ontology analysis revealed enrichment in processes associated to cellular movement and lipid signaling, whereas the enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways included networks for calcium signaling and cell adhesion molecules, among others. This is the first deep transcriptomic analysis of macrophages in the context of Trpc3 deficiency and the data presented constitutes a unique resource to further explore functions of TRPC3 in macrophage biology.
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Affiliation(s)
- Sivarajan Kumarasamy
- Department of Physiology and Pharmacology, and Center for Hypertension and Personalized Medicine, University of Toledo College of Medicine and Life Sciences, University of Toledo Health Science Campus, 3000 Transverse Dr., Toledo, Ohio 43614 USA
| | - Sumeet Solanki
- Department of Physiology and Pharmacology, and Center for Hypertension and Personalized Medicine, University of Toledo College of Medicine and Life Sciences, University of Toledo Health Science Campus, 3000 Transverse Dr., Toledo, Ohio 43614 USA
| | - Oluwatomisin T Atolagbe
- Department of Physiology and Pharmacology, and Center for Hypertension and Personalized Medicine, University of Toledo College of Medicine and Life Sciences, University of Toledo Health Science Campus, 3000 Transverse Dr., Toledo, Ohio 43614 USA
| | - Bina Joe
- Department of Physiology and Pharmacology, and Center for Hypertension and Personalized Medicine, University of Toledo College of Medicine and Life Sciences, University of Toledo Health Science Campus, 3000 Transverse Dr., Toledo, Ohio 43614 USA
| | - Lutz Birnbaumer
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, 111 TW Alexander Dr., Research Triangle Park, North Carolina 27709 USA.,Institute of Biomedical Research (BIOMED UCA-CONICET), Faculty of Medical Sciences, Av. Alicia Moreau de Justo 1600, C1107AFF Buenos Aires, Argentina
| | - Guillermo Vazquez
- Department of Physiology and Pharmacology, and Center for Hypertension and Personalized Medicine, University of Toledo College of Medicine and Life Sciences, University of Toledo Health Science Campus, 3000 Transverse Dr., Toledo, Ohio 43614 USA
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Short term memory of Caenorhabditis elegans against bacterial pathogens involves CREB transcription factor. Immunobiology 2016; 222:684-692. [PMID: 28069295 DOI: 10.1016/j.imbio.2016.12.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 12/26/2016] [Accepted: 12/27/2016] [Indexed: 11/24/2022]
Abstract
One of the key issues pertaining to the control of memory is to respond to a consistently changing environment or microbial niche present in it. Human cyclic AMP response element binding protein (CREB) transcription factor which plays a crucial role in memory has a homolog in C. elegans, crh-1. crh-1 appears to influence memory processes to certain extent by habituation of the host to a particular environment. The discrimination between the pathogen and a non-pathogen is essential for C. elegans in a microbial niche which determines its survival. Training the nematodes in the presence of a virulent pathogen (S. aureus) and an opportunistic pathogen (P. mirabilis) separately exhibits a different behavioural paradigm. This appears to be dependent on the CREB transcription factor. Here we show that C. elegans homolog crh-1 helps in memory response for a short term against the interacting pathogens. Following conditioning of the nematodes to S. aureus and P. mirabilis, the wild type nematodes exhibited a positive response towards the respective pathogens which diminished slowly after 2h. By contrast, the crh-1 deficient nematodes had a defective memory post conditioning. The molecular data reinforces the importance of crh-1 gene in retaining the memory of nematode. Our results also suggest that involvement of neurotransmitters play a crucial role in modulating the memory of the nematode with the assistance of CREB. Therefore, we elucidate that CREB is responsible for the short term memory response in C. elegans against bacterial pathogens.
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Li W, Choi TW, Ahnn J, Lee SK. Allele-Specific Phenotype Suggests a Possible Stimulatory Activity of RCAN-1 on Calcineurin in Caenorhabditis elegans. Mol Cells 2016; 39:827-833. [PMID: 27871170 PMCID: PMC5125939 DOI: 10.14348/molcells.2016.0222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 10/27/2016] [Accepted: 10/31/2016] [Indexed: 11/27/2022] Open
Abstract
Regulator of calcineurin 1 (RCAN1) binds to calcineurin through the PxIxIT motif, which is evolutionarily conserved. SP repeat phosphorylation in RCAN1 is required for its complete function. The specific interaction between RCAN1 and calcineurin is critical for calcium/calmodulin-dependent regulation of calcineurin serine/threonine phosphatase activity. In this study, we investigated two available deletion rcan-1 mutants in Caenorhabditis elegans, which proceed differently for transcription and translation. We found that rcan-1 may be required for calcineurin activity and possess calcineurin-independent function in body growth and egg-laying behavior. In the genetic background of enhanced calcineurin activity, the rcan-1 mutant expressing a truncated RCAN-1 which retains the calcineurin-binding PxIxIT motif but misses SP repeats stimulated growth, while rcan-1 lack mutant resulted in hyperactive egg-laying suppression. These data suggest rcan-1 has unknown functions independent of calcineurin, and may be a stimulatory calcineurin regulator under certain circumstances.
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Affiliation(s)
- Weixun Li
- Department of Life Science, Hanyang University, Seoul 04763,
Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763,
Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763,
Korea
| | - Tae-Woo Choi
- Department of Life Science, Hanyang University, Seoul 04763,
Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763,
Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763,
Korea
| | - Joohong Ahnn
- Department of Life Science, Hanyang University, Seoul 04763,
Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763,
Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763,
Korea
| | - Sun-Kyung Lee
- Department of Life Science, Hanyang University, Seoul 04763,
Korea
- BK21 PLUS Life Science for BDR Team, Hanyang University, Seoul 04763,
Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul 04763,
Korea
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