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Qu JH, Tarasov KV, Chakir K, Tarasova YS, Riordon DR, Lakatta EG. Proteomic Landscape and Deduced Functions of the Cardiac 14-3-3 Protein Interactome. Cells 2022; 11:cells11213496. [PMID: 36359893 PMCID: PMC9654263 DOI: 10.3390/cells11213496] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/17/2022] [Accepted: 10/24/2022] [Indexed: 11/09/2022] Open
Abstract
Rationale: The 14-3-3 protein family is known to interact with many proteins in non-cardiac cell types to regulate multiple signaling pathways, particularly those relating to energy and protein homeostasis; and the 14-3-3 network is a therapeutic target of critical metabolic and proteostatic signaling in cancer and neurological diseases. Although the heart is critically sensitive to nutrient and energy alterations, and multiple signaling pathways coordinate to maintain the cardiac cell homeostasis, neither the structure of cardiac 14-3-3 protein interactome, nor potential functional roles of 14-3-3 protein–protein interactions (PPIs) in heart has been explored. Objective: To establish the comprehensive landscape and characterize the functional role of cardiac 14-3-3 PPIs. Methods and Results: We evaluated both RNA expression and protein abundance of 14-3-3 isoforms in mouse heart, followed by co-immunoprecipitation of 14-3-3 proteins and mass spectrometry in left ventricle. We identified 52 proteins comprising the cardiac 14-3-3 interactome. Multiple bioinformatic analyses indicated that more than half of the proteins bound to 14-3-3 are related to mitochondria; and the deduced functions of the mitochondrial 14-3-3 network are to regulate cardiac ATP production via interactions with mitochondrial inner membrane proteins, especially those in mitochondrial complex I. Binding to ribosomal proteins, 14-3-3 proteins likely coordinate protein synthesis and protein quality control. Localizations of 14-3-3 proteins to mitochondria and ribosome were validated via immunofluorescence assays. The deduced function of cardiac 14-3-3 PPIs is to regulate cardiac metabolic homeostasis and proteostasis. Conclusions: Thus, the cardiac 14-3-3 interactome may be a potential therapeutic target in cardiovascular metabolic and proteostatic disease states, as it already is in cancer therapy.
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Eisa A, Dey S, Ignatious A, Nofal W, Hess RA, Kurokawa M, Kline D, Vijayaraghavan S. The protein YWHAE (14-3-3 epsilon) in spermatozoa is essential for male fertility. Andrology 2021; 9:312-328. [PMID: 32657535 PMCID: PMC8356477 DOI: 10.1111/andr.12865] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/28/2022]
Abstract
BACKGROUND Spermatogenesis is a complex biological process highlighted by synthesis and activation of proteins that regulate meiosis and cellular differentiation occur during spermatogenesis. 14-3-3 proteins are adaptor proteins that play critical roles in kinase signaling, especially for regulation of cell cycle and apoptosis in eukaryotic cells. There are seven isoforms of the 14-3-3 family proteins encoded by seven genes (β, ε, γ, η, θ/τ, ζ and σ). 14-3-3 isoforms have been shown to have many interacting partners in several tissues including testis. OBJECTIVE While it is known that 14-3-3 proteins are expressed in the functions of testis and spermatozoon, the role for each of the seven isoforms is not known. In this study, we investigated the roles of 14-3-3η and 14-3-3ε isoforms in spermatogenesis. MATERIALS AND METHODS To study the in vivo function of 14-3-3η and 14-3-3ε in spermatogenesis, we generated testis-specific and global knockout mice for each of 14-3-3η and 14-3-3ε isoforms (CKO and GKO, respectively). Computer-assisted semen analysis was used to assess sperm motility, while immunohistochemical studies were conducted to check spermatogenesis. RESULTS Although both 14-3-3η and 14-3-3ε isoforms were present in mouse testis, only the expression of 14-3-3ε, but not 14-3-3η, was detected in spermatozoa. Mice lacking 14-3-3η were normal and fertile while 14-3-3ε CKO and GKO males showed infertility. Low sperm count with higher abnormal spermatozoa was seen in 14-3-3ε CKO mice. The motility of 14-3-3ε knockout spermatozoa was lower than that of the control. A reduction in the phosphorylation of both glycogen synthase kinase 3 and PP1γ2 was also seen in spermatozoa from 14-3-3ε CKO mice, suggesting a specific role of 14-3-3ε in spermatogenesis, sperm motility, and fertility. DISCUSSION AND CONCLUSION This is the first demonstration that of the seven 14-3-3 isoforms, 14-3-3ε is essential for normal sperm function and male fertility.
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Affiliation(s)
- Alaa Eisa
- Department of Medical Laboratories Technology, College of Applied Medical Sciences, Taibah University, Madina, Saudi Arabia
| | - Souvik Dey
- Biology Department, Kent State University, Kent, OH, USA
| | - Alex Ignatious
- Biology Department, Kent State University, Kent, OH, USA
| | - Wesam Nofal
- School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - Rex A. Hess
- Department of Veterinary Biosciences, University Of Illinois, Urbana, IL, USA
| | | | - Douglas Kline
- Biology Department, Kent State University, Kent, OH, USA
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Eisa AA, De S, Detwiler A, Gilker E, Ignatious AC, Vijayaraghavan S, Kline D. YWHA (14-3-3) protein isoforms and their interactions with CDC25B phosphatase in mouse oogenesis and oocyte maturation. BMC DEVELOPMENTAL BIOLOGY 2019; 19:20. [PMID: 31640562 PMCID: PMC6805688 DOI: 10.1186/s12861-019-0200-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 09/13/2019] [Indexed: 12/21/2022]
Abstract
Background Immature mammalian oocytes are held arrested at prophase I of meiosis by an inhibitory phosphorylation of cyclin-dependent kinase 1 (CDK1). Release from this meiotic arrest and germinal vesicle breakdown is dependent on dephosphorylation of CDK1 by the protein, cell cycle division 25B (CDC25B). Evidence suggests that phosphorylated CDC25B is bound to YWHA (14-3-3) proteins in the cytoplasm of immature oocytes and is thus maintained in an inactive form. The importance of YWHA in meiosis demands additional studies. Results Messenger RNA for multiple isoforms of the YWHA protein family was detected in mouse oocytes and eggs. All seven mammalian YWHA isoforms previously reported to be expressed in mouse oocytes, were found to interact with CDC25B as evidenced by in situ proximity ligation assays. Interaction of YWHAH with CDC25B was indicated by Förster Resonance Energy Transfer (FRET) microscopy. Intracytoplasmic microinjection of oocytes with R18, a known, synthetic, non-isoform-specific, YWHA-blocking peptide promoted germinal vesicle breakdown. This suggests that inhibiting the interactions between YWHA proteins and their binding partners releases the oocyte from meiotic arrest. Microinjection of isoform-specific, translation-blocking morpholino oligonucleotides to knockdown or downregulate YWHA protein synthesis in oocytes suggested a role for a specific YWHA isoform in maintaining the meiotic arrest. More definitively however, and in contrast to the knockdown experiments, oocyte-specific and global deletion of two isoforms of YWHA, YWHAH (14-3-3 eta) or YWHAE (14-3-3 epsilon) indicated that the complete absence of either or both isoforms does not alter oocyte development and release from the meiotic prophase I arrest. Conclusions Multiple isoforms of the YWHA protein are expressed in mouse oocytes and eggs and interact with the cell cycle protein CDC25B, but YWHAH and YWHAE isoforms are not essential for normal mouse oocyte maturation, fertilization and early embryonic development.
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Affiliation(s)
- Alaa A Eisa
- School of Biomedical Sciences, Kent State University, Kent, OH, 22422, USA
| | - Santanu De
- Department of Biological Sciences, Nova Southeastern University, Fort Lauderdale, FL, 33314, USA
| | - Ariana Detwiler
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
| | - Eva Gilker
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | | | | | - Douglas Kline
- Department of Biological Sciences, Kent State University, Kent, OH, 44242, USA.
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Ng YS, Sorvina A, Bader CA, Weiland F, Lopez AF, Hoffmann P, Shandala T, Brooks DA. Proteome Analysis of Drosophila Mutants Identifies a Regulatory Role for 14-3-3ε in Metabolic Pathways. J Proteome Res 2017; 16:1976-1987. [PMID: 28365999 DOI: 10.1021/acs.jproteome.6b01032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The evolutionary conserved family of 14-3-3 proteins appears to have a role in integrating numerous intracellular pathways, including signal transduction, intracellular trafficking, and metabolism. However, little is known about how this interactive network might be affected by the direct abrogation of 14-3-3 function. The loss of Drosophila 14-3-3ε resulted in reduced survival of mutants during larval-to-adult transition, which is known to depend on an energy supply coming from the histolysis of fat body tissue. Here we report a differential proteomic analysis of larval fat body tissue at the onset of larval-to-adult transition, with the loss of 14-3-3ε resulting in the altered abundance of 16 proteins. These included proteins linked to protein biosynthesis, glycolysis, tricarboxylic acid cycle, and lipid metabolic pathways. The ecdysone receptor (EcR), which is responsible for initiating the larval-to-adult transition, colocalized with 14-3-3ε in wild-type fat body tissues. The altered protein abundance in 14-3-3ε mutant fat body tissue was associated with transcriptional deregulation of alcohol dehydrogenase, fat body protein 1, and lamin genes, which are known targets of the EcR. This study indicates that 14-3-3ε has a critical role in cellular metabolism involving either molecular crosstalk with the EcR or direct interaction with metabolic proteins.
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Affiliation(s)
- Yeap S Ng
- Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Alexandra Sorvina
- Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Christie A Bader
- Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Florian Weiland
- Adelaide Proteomics Center, School of Molecular and Biomedical Sciences, University of Adelaide , Adelaide, South Australia 5005, Australia
| | - Angel F Lopez
- Centre for Cancer Biology , Adelaide, South Australia 5000, Australia
| | - Peter Hoffmann
- Adelaide Proteomics Center, School of Molecular and Biomedical Sciences, University of Adelaide , Adelaide, South Australia 5005, Australia
| | | | - Douglas A Brooks
- Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia , Adelaide, South Australia 5001, Australia
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Wang X, Chang L, Tong Z, Wang D, Yin Q, Wang D, Jin X, Yang Q, Wang L, Sun Y, Huang Q, Guo A, Peng M. Proteomics Profiling Reveals Carbohydrate Metabolic Enzymes and 14-3-3 Proteins Play Important Roles for Starch Accumulation during Cassava Root Tuberization. Sci Rep 2016; 6:19643. [PMID: 26791570 PMCID: PMC4726164 DOI: 10.1038/srep19643] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 12/14/2015] [Indexed: 02/07/2023] Open
Abstract
Cassava is one of the most important root crops as a reliable source of food and carbohydrates. Carbohydrate metabolism and starch accumulation in cassava storage root is a cascade process that includes large amounts of proteins and cofactors. Here, comparative proteomics were conducted in cassava root at nine developmental stages. A total of 154 identified proteins were found to be differentially expressed during starch accumulation and root tuberization. Many enzymes involved in starch and sucrose metabolism were significantly up-regulated, and functional classification of the differentially expressed proteins demonstrated that the majority were binding-related enzymes. Many proteins were took part in carbohydrate metabolism to produce energy. Among them, three 14-3-3 isoforms were induced to be clearly phosphorylated during storage root enlargement. Overexpression of a cassava 14-3-3 gene in Arabidopsis thaliana confirmed that the older leaves of these transgenic plants contained higher sugar and starch contents than the wild-type leaves. The 14-3-3 proteins and their binding enzymes may play important roles in carbohydrate metabolism and starch accumulation during cassava root tuberization. These results not only deepened our understanding of the tuberous root proteome, but also uncovered new insights into carbohydrate metabolism and starch accumulation during cassava root enlargement.
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Affiliation(s)
- Xuchu Wang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China.,College of Agriculture, Hainan University, Haikou, Hainan 570228, China
| | - Lili Chang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China.,College of Agriculture, Hainan University, Haikou, Hainan 570228, China
| | - Zheng Tong
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Dongyang Wang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China.,College of Agriculture, Hainan University, Haikou, Hainan 570228, China
| | - Qi Yin
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China.,College of Agriculture, Hainan University, Haikou, Hainan 570228, China
| | - Dan Wang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Xiang Jin
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Qian Yang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Liming Wang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Yong Sun
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Qixing Huang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Anping Guo
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China
| | - Ming Peng
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China.,College of Agriculture, Hainan University, Haikou, Hainan 570228, China
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Bhattacharjee R, Goswami S, Dudiki T, Popkie AP, Phiel CJ, Kline D, Vijayaraghavan S. Targeted disruption of glycogen synthase kinase 3A (GSK3A) in mice affects sperm motility resulting in male infertility. Biol Reprod 2015; 92:65. [PMID: 25568307 DOI: 10.1095/biolreprod.114.124495] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The signaling enzyme glycogen synthase kinase 3 (GSK3) exists as two isoforms-GSK3A and GSK3B. Protein phosphorylation by GSK3 has important signaling roles in several cells. In our past work, we found that both isoforms of GSK3 are present in mouse sperm and that catalytic GSK3 activity correlates with motility of sperm from several species. Here, we examined the role of Gsk3a in male fertility using a targeted gene knockout (KO) approach. The mutant mice are viable, but have a male infertility phenotype, while female fertility is unaffected. Testis weights of Gsk3a(-/-) mice are normal and sperm are produced in normal numbers. Although spermatogenesis is apparently unimpaired, sperm motility parameters in vitro are impaired. In addition, the flagellar waveform appears abnormal, characterized by low amplitude of flagellar beat. Sperm ATP levels were lower in Gsk3a(-/-) mice compared to wild-type animals. Protein phosphatase PP1 gamma2 protein levels were unaltered, but its catalytic activity was elevated in KO sperm. Remarkably, tyrosine phosphorylation of hexokinase and capacitation-associated changes in tyrosine phosphorylation of proteins are absent or significantly lower in Gsk3a(-/-) sperm. The GSK3B isoform was present and unaltered in testis and sperm of Gsk3a(-/-) mice, showing the inability of GSK3B to substitute for GSK3A in this context. Our studies show that sperm GSK3A is essential for male fertility. In addition, the GSK3A isoform, with its highly conserved glycine-rich N terminus in mammals, may have an isoform-specific role in its requirement for normal sperm motility and fertility.
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Affiliation(s)
| | - Suranjana Goswami
- Department of Biological Sciences, Kent State University, Kent, Ohio
| | - Tejasvi Dudiki
- Department of Biological Sciences, Kent State University, Kent, Ohio
| | - Anthony P Popkie
- Laboratory of Cancer Epigenomics, Center for Epigenetics, Van Andel Research Institute, Grand Rapids, Michigan
| | - Christopher J Phiel
- Department of Integrative Biology, University of Colorado Denver, Denver, Colorado
| | - Douglas Kline
- Department of Biological Sciences, Kent State University, Kent, Ohio
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Tappenden DM, Hwang HJ, Yang L, Thomas RS, LaPres JJ. The Aryl-Hydrocarbon Receptor Protein Interaction Network (AHR-PIN) as Identified by Tandem Affinity Purification (TAP) and Mass Spectrometry. J Toxicol 2013; 2013:279829. [PMID: 24454361 PMCID: PMC3870133 DOI: 10.1155/2013/279829] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 10/09/2013] [Accepted: 10/14/2013] [Indexed: 12/28/2022] Open
Abstract
The aryl-hydrocarbon receptor (AHR), a ligand activated PAS superfamily transcription factor, mediates most, if not all, of the toxicity induced upon exposure to various dioxins, dibenzofurans, and planar polyhalogenated biphenyls. While AHR-mediated gene regulation plays a central role in the toxic response to dioxin exposure, a comprehensive understanding of AHR biology remains elusive. AHR-mediated signaling starts in the cytoplasm, where the receptor can be found in a complex with the heat shock protein of 90 kDa (Hsp90) and the immunophilin-like protein, aryl-hydrocarbon receptor-interacting protein (AIP). The role these chaperones and other putative interactors of the AHR play in the toxic response is not known. To more comprehensively define the AHR-protein interaction network (AHR-PIN) and identify other potential pathways involved in the toxic response, a proteomic approach was undertaken. Using tandem affinity purification (TAP) and mass spectrometry we have identified several novel protein interactions with the AHR. These interactions physically link the AHR to proteins involved in the immune and cellular stress responses, gene regulation not mediated directly via the traditional AHR:ARNT heterodimer, and mitochondrial function. This new insight into the AHR signaling network identifies possible secondary signaling pathways involved in xenobiotic-induced toxicity.
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Affiliation(s)
- Dorothy M. Tappenden
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824-1319, USA
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824-1319, USA
| | - Hye Jin Hwang
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824-1319, USA
- Center for Mitochondrial Science and Medicine, Michigan State University, East Lansing, MI 48824-1319, USA
| | - Longlong Yang
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709, USA
| | - Russell S. Thomas
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709, USA
| | - John J. LaPres
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824-1319, USA
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824-1319, USA
- Center for Mitochondrial Science and Medicine, Michigan State University, East Lansing, MI 48824-1319, USA
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The HDAC inhibitor LBH589 induces ERK-dependent prometaphase arrest in prostate cancer via HDAC6 inactivation and down-regulation. PLoS One 2013; 8:e73401. [PMID: 24023871 PMCID: PMC3762759 DOI: 10.1371/journal.pone.0073401] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 07/19/2013] [Indexed: 01/03/2023] Open
Abstract
Histone deacetylase inhibitors (HDACIs) have potent anti-cancer activity in a variety of cancer models. Understanding the molecular mechanisms involved in the therapeutic responsiveness of HDACI is needed before its clinical application. This study aimed to determine if a potent HDACI, LBH589 (Panobinostat), had differential therapeutic responsiveness towards LNCaP and PC-3 prostate cancer (PCa) cells. The former showed prometaphase arrest with subsequent apoptosis upon LBH589 treatment, while the latter was less sensitive and had late G2 arrest. The LBH589 treatment down-regulated HDAC6 and sustained ERK activation, and contributed to prometaphase arrest. Mechanistically, LBH589 inhibited HDAC6 activity, caused its dissociation from protein phosphatase PP1α, and increased 14-3-3ζ acetylation. Acetylated 14-3-3ζ released its mask effect on serine 259 of c-Raf and serine 216 of Cdc25C subsequent to de-phosphorylation by PP1α, which contributed to ERK activation. Enhanced ERK activity by LBH589 further down-regulated HDAC6 protein levels and sustained ERK activation by free-forward regulation. The sustained Cdc25C and ERK activation resulted in early M-phase (prometaphase) arrest and subsequent apoptosis in the most sensitive LNCaP cells but not in PC-3 cells. This study provides pre-clinical evidence that HDAC6 may serve as a sensitive therapeutic target in the treatment of prostate cancer with HDACI LBH589 for clinical translation. This study also posits a novel mechanism of HDAC6 participation in regulating the c-Raf-PP1-ERK signaling pathway and contributing to M phase cell-cycle transition.
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MacLeod G, Varmuza S. The application of proteomic approaches to the study of mammalian spermatogenesis and sperm function. FEBS J 2013; 280:5635-51. [DOI: 10.1111/febs.12461] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 07/04/2013] [Accepted: 07/26/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Graham MacLeod
- Department of Cell & Systems Biology; University of Toronto; ON Canada
| | - Susannah Varmuza
- Department of Cell & Systems Biology; University of Toronto; ON Canada
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Stanton PG, Sluka P, Foo CFH, Stephens AN, Smith AI, McLachlan RI, O'Donnell L. Proteomic changes in rat spermatogenesis in response to in vivo androgen manipulation; impact on meiotic cells. PLoS One 2012; 7:e41718. [PMID: 22860010 PMCID: PMC3408499 DOI: 10.1371/journal.pone.0041718] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 06/26/2012] [Indexed: 01/11/2023] Open
Abstract
The production of mature sperm is reliant on androgen action within the testis, and it is well established that androgens act on receptors within the somatic Sertoli cells to stimulate male germ cell development. Mice lacking Sertoli cell androgen receptors (AR) show late meiotic germ cell arrest, suggesting Sertoli cells transduce the androgenic stimulus co-ordinating this essential step in spermatogenesis. This study aimed to identify germ cell proteins responsive to changes in testicular androgen levels and thereby elucidate mechanisms by which androgens regulate meiosis. Testicular androgen levels were suppressed for 9 weeks using testosterone and estradiol-filled silastic implants, followed by a short period of either further androgen suppression (via an AR antagonist) or the restoration of intratesticular testosterone levels. Comparative proteomics were performed on protein extracts from enriched meiotic cell preparations from adult rats undergoing androgen deprivation and replacement in vivo. Loss of androgenic stimulus caused changes in proteins with known roles in meiosis (including Nasp and Hsp70–2), apoptosis (including Diablo), cell signalling (including 14-3-3 isoforms), oxidative stress, DNA repair, and RNA processing. Immunostaining for oxidised DNA adducts confirmed spermatocytes undergo oxidative stress-induced DNA damage during androgen suppression. An increase in PCNA and an associated ubiquitin-conjugating enzyme (Ubc13) suggested a role for PCNA-mediated regulation of DNA repair pathways in spermatocytes. Changes in cytoplasmic SUMO1 localisation in spermatocytes were paralleled by changes in the levels of free SUMO1 and of a subunit of its activating complex, suggesting sumoylation in spermatocytes is modified by androgen action on Sertoli cells. We conclude that Sertoli cells, in response to androgens, modulate protein translation and post-translational events in spermatocytes that impact on their metabolism, survival, and completion of meiosis.
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Affiliation(s)
- Peter G Stanton
- Prince Henry's Institute, Monash Medical Centre, Clayton, Victoria, Australia.
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