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Rosyada ZNA, Pardede BP, Kaiin EM, Gunawan M, Maulana T, Said S, Tumbelaka LITA, Solihin DD, Ulum MF, Purwantara B. A proteomic approach to identifying spermatozoa proteins in Indonesian native Madura bulls. Front Vet Sci 2023; 10:1287676. [PMID: 38111731 PMCID: PMC10725959 DOI: 10.3389/fvets.2023.1287676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Accepted: 11/06/2023] [Indexed: 12/20/2023] Open
Abstract
Proteins assist sperm mature, transit the female reproductive tract, and recognise sperm oocytes. Indigenous Indonesian bulls, Madura bulls, have not been studied for reproductive proteomics. As local Indonesian beef livestock, Madura cattle assist in achieving food security; hence, their number must be improved. Thus, the identification of molecular proteomics-based bull fertility biomarkers is needed. This study aimed to characterise the sperm fertility function of the superior Madura bull (Bos indicus × Bos Javanicus) spermatozoa proteome. Frozen semen from eight Madura superior bulls (Bos indicus × Bos javanicus) aged 4-8 years was obtained from the artificial insemination centre (AIC) in Singosari and Lembang. Madura superior bulls are those that have passed the bull breeding soundness evaluation. Frozen sperm were thawed and centrifuged at 3000 × g for 30 min. Proteins in sperm were characterised through proteomic analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The resulting gene symbols for each protein were then subjected to bioinformatics tools, including UniProt, DAVID, and STRING databases. Regarding sperm fertility, the analysis revealed that 15 proteins were identified in the sperm of Madura bulls. Amongst the identified proteins, the superior Madura bull sperm contained several motilities, energy-related proteins, and chaperone proteins. A substantial portion of characterised proteins are linked to metabolic pathways and the tricarboxylic acid (TCA) cycle, contributing to sperm energy production. In conclusion, the first in-depth proteome identification of sperm related to sperm quality and bull fertility of a unique indigenous Madura breed of Indonesia was performed using the LC-MS/MS proteomic method. These findings may serve as a reference point for further studies related to the functions of bovine sperm and biomarkers of fertility and sperm quality.
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Affiliation(s)
- Zulfi Nur Amrina Rosyada
- Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University, Bogor, Indonesia
- Research Center for Applied Zoology, National Research and Innovation Agency (BRIN), Bogor, Indonesia
- Division of Veterinary Anatomy, Faculty of Veterinary Medicine, Universitas Airlangga, Surabaya, Indonesia
| | - Berlin Pandapotan Pardede
- Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University, Bogor, Indonesia
- Research Center for Applied Zoology, National Research and Innovation Agency (BRIN), Bogor, Indonesia
| | - Ekayanti Mulyawati Kaiin
- Research Center for Applied Zoology, National Research and Innovation Agency (BRIN), Bogor, Indonesia
| | - Muhammad Gunawan
- Research Center for Applied Zoology, National Research and Innovation Agency (BRIN), Bogor, Indonesia
| | - Tulus Maulana
- Research Center for Applied Zoology, National Research and Innovation Agency (BRIN), Bogor, Indonesia
| | - Syahruddin Said
- Research Center for Applied Zoology, National Research and Innovation Agency (BRIN), Bogor, Indonesia
| | - Ligaya I. T. A Tumbelaka
- Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University, Bogor, Indonesia
| | | | - Mokhamad Fakhrul Ulum
- Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University, Bogor, Indonesia
| | - Bambang Purwantara
- Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University, Bogor, Indonesia
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Gardela J, Ruiz-Conca M, Palomares A, Olvera-Maneu S, García-Calvo L, López-Béjar M, Martínez-Pastor F, Álvarez-Rodríguez M. Effect of Honey, Coenzyme Q10, and β-Carotene/α-Tocopherol as Novel Additives in Rabbit-Sperm Cryopreservation Extender. Animals (Basel) 2023; 13:2392. [PMID: 37508170 PMCID: PMC10376550 DOI: 10.3390/ani13142392] [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: 05/19/2023] [Revised: 06/22/2023] [Accepted: 07/21/2023] [Indexed: 07/30/2023] Open
Abstract
The effectiveness of rabbit-sperm cryopreservation is still below average compared to other domestic species. After the sperm cryopreservation process, post-thawing parameters like motility and membrane integrity are significantly compromised. The use of new extender constituents is an approach that can be used to improve the effectiveness of cryopreservation. Accordingly, we used honey (1.25, 2.5, 5, and 10%), coenzyme Q10 (100 and 200 μM), and β-carotene/α-tocopherol (500 μM/620 μM and 250 μM/310 μM) as candidate components for rabbit-sperm extenders during cryopreservation. Ejaculates from commercial adult rabbit bucks (n = 5) were cryopreserved using conventional freezing. Several post-thawing sperm parameters were assessed, including total motility, membrane integrity, viability, nuclear membrane integrity, acrosome reaction, and mitochondrial membrane potential and activation. Additionally, we performed hormonal analyses of the seminal plasma. Moreover, we analyzed the post-thawing levels of a molecular marker of sperm quality, proAKAP4, which was used in rabbits for the first time. Our findings showed that the 2.5% honey supplementation increased the post-thawing sperm motility (13.75 ± 3.75%) compared to the greater concentrations employed. However, the post-thawing motility was negatively affected by the coenzyme Q10 (0%, in both groups) but was not affected by the β-carotene/α-tocopherol supplementation (22 ± 18.15%, and 11.67 ± 10.17%). In conclusion, the cryopreservation protocols of this study did not help to maintain the sperm parameters after thawing. Further studies are required to identify novel protocols to mitigate the damage caused to rabbit sperm during cryopreservation.
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Affiliation(s)
- Jaume Gardela
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Mateo Ruiz-Conca
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Anna Palomares
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Sergi Olvera-Maneu
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Laura García-Calvo
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Manel López-Béjar
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Felipe Martínez-Pastor
- Institute of Animal Health and Cattle Development (INDEGSAL) and Department of Molecular Biology (Cell Biology), Universidad de León, 24009 León, Spain
| | - Manuel Álvarez-Rodríguez
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
- Department of Animal Reproduction, National Institute for Agriculture and Food Research and Technology, Spanish National Research Council (INIA-CSIC), 28040 Madrid, Spain
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Nozawa K, Garcia TX, Kent K, Leng M, Jain A, Malovannaya A, Yuan F, Yu Z, Ikawa M, Matzuk MM. Testis-specific serine kinase 3 is required for sperm morphogenesis and male fertility. Andrology 2023; 11:826-839. [PMID: 36306217 PMCID: PMC10267670 DOI: 10.1111/andr.13314] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/16/2022] [Accepted: 09/28/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND The importance of phosphorylation in sperm during spermatogenesis has not been pursued extensively. Testis-specific serine kinase 3 (Tssk3) is a conserved gene, but TSSK3 kinase functions and phosphorylation substrates of TSSK3 are not known. OBJECTIVE The goals of our studies were to understand the mechanism of action of TSSK3. MATERIALS AND METHODS We analyzed the localization of TSSK3 in sperm, used CRISPR/Cas9 to generate Tssk3 knockout (KO) mice in which nearly all of the Tssk3 open reading frame was deleted (ensuring it is a null mutation), analyzed the fertility of Tssk3 KO mice by breeding mice for 4 months, and conducted phosphoproteomics analysis of male testicular germ cells. RESULTS TSSK3 is expressed in elongating sperm and localizes to the sperm tail. To define the essential roles of TSSK3 in vivo, heterozygous (HET) or homozygous KO male mice were mated with wild-type females, and fertility was assessed over 4 months; Tssk3 KO males are sterile, whereas HET males produced normal litter sizes. The absence of TSSK3 results in disorganization of all stages of testicular seminiferous epithelium and significantly increased vacuolization of germ cells, leading to dramatically reduced sperm counts and abnormal sperm morphology; despite these histologic changes, Tssk3 null mice have normal testis size. To elucidate the mechanisms causing the KO phenotype, we conducted phosphoproteomics using purified germ cells from Tssk3 HET and KO testes. We found that proteins implicated in male infertility, such as GAPDHS, ACTL7A, ACTL9, and REEP6, showed significantly reduced phosphorylation in KO testes compared to HET testes, despite unaltered total protein levels. CONCLUSIONS We demonstrated that TSSK3 is essential for male fertility and crucial for phosphorylation of multiple infertility-related proteins. These studies and the pathways in which TSSK3 functions have implications for human male infertility and nonhormonal contraception.
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Affiliation(s)
- Kaori Nozawa
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
| | - Thomas X. Garcia
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
- Scott Department of Urology, Baylor College of Medicine, Houston, TX
| | - Katarzyna Kent
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
| | - Mei Leng
- Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX
| | - Antrix Jain
- Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX
| | - Anna Malovannaya
- Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX
| | - Fei Yuan
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
| | - Zhifeng Yu
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
| | - Masahito Ikawa
- Department of Experimental Genome Research, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
- The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, Japan
| | - Martin M. Matzuk
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
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Hackerova L, Klusackova B, Zigo M, Zelenkova N, Havlikova K, Krejcirova R, Sedmikova M, Sutovsky P, Komrskova K, Postlerova P, Simonik O. Modulatory effect of MG-132 proteasomal inhibition on boar sperm motility during in vitro capacitation. Front Vet Sci 2023; 10:1116891. [PMID: 37035827 PMCID: PMC10077870 DOI: 10.3389/fvets.2023.1116891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 03/02/2023] [Indexed: 04/11/2023] Open
Abstract
A series of biochemical and biophysical changes during sperm capacitation initiates various signaling pathways related to protein phosphorylation leading to sperm hyperactivation, simultaneously with the regulation of proteasomal activity responsible for protein degradation and turnover. Our study aimed to unveil the role of the proteasome in the regulation of boar sperm motility, hyperactivated status, tyrosine phosphorylation, and total protein ubiquitination. The proteolytic activity of the 20S proteasomal core was inhibited by MG-132 in concentrations of 10, 25, 50, and 100 μM; and monitored parameters were analyzed every hour during 3 h of in vitro capacitation (IVC). Sperm motility and kinematic parameters were analyzed by Computer Assisted Sperm Analysis (CASA) during IVC, showing a significant, negative, dose-dependent effect of MG-132 on total and progressive sperm motility (TMOT, PMOT, respectively). Furthermore, proteasomal inhibition by 50 and 100 μM MG-132 had a negative impact on velocity-based kinematic sperm parameters (VSL, VAP, and VCL). Parameters related to the progressivity of sperm movement (LIN, STR) and ALH were the most affected by the highest inhibitor concentration (100 μM). Cluster analysis revealed that the strongest proteasome-inhibiting treatment had a significant effect (p ≤ 0.05) on the hyperactivated sperm subpopulation. The flow cytometric viability results proved that reduced TMOT and PMOT were not caused by disruption of the integrity of the plasma membrane. Neither the protein tyrosine phosphorylation profile changes nor the accumulation of protein ubiquitination was observed during the course of capacitation under proteasome inhibition. In conclusion, inhibition of the proteasome reduced the ability of spermatozoa to undergo hyperactivation; however, there was no significant effect on the level of protein tyrosine phosphorylation and accumulation of ubiquitinated proteins. These effects might be due to the presence of compensatory mechanisms or the alteration of various ubiquitin-proteasome system-regulated pathways.
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Affiliation(s)
- Lenka Hackerova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
| | - Barbora Klusackova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
| | - Michal Zigo
- Division of Animal Sciences, University of Missouri, Columbia, MO, United States
| | - Natalie Zelenkova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
| | - Katerina Havlikova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
| | - Romana Krejcirova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
| | - Marketa Sedmikova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
| | - Peter Sutovsky
- Division of Animal Sciences, University of Missouri, Columbia, MO, United States
- Department of Obstetrics, Gynecology and Women's Health, University of Missouri, Columbia, MO, United States
| | - Katerina Komrskova
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec, Czechia
- Department of Zoology, Faculty of Science, Charles University, Prague, Czechia
| | - Pavla Postlerova
- Department of Veterinary Sciences, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Prague, Czechia
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec, Czechia
- *Correspondence: Pavla Postlerova
| | - Ondrej Simonik
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec, Czechia
- Ondrej Simonik
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5
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ProAKAP4 Concentration Is Related to Sperm Motility and Motile Sperm Subpopulations in Frozen-Thawed Horse Semen. Animals (Basel) 2022; 12:ani12233417. [PMID: 36496938 PMCID: PMC9738597 DOI: 10.3390/ani12233417] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/18/2022] [Accepted: 12/02/2022] [Indexed: 12/10/2022] Open
Abstract
ProAKAP4 is the precursor of AKAP4 (A-kinase Anchor protein 4), the main structural protein of the fibrous sheath of sperm. The amount of proAKAP4 reflects the ability of spermatozoa to maintain the flagellum activity and functionality up to the site of fertilization and is positively correlated with progressive motility in several mammalian species. The aim of this study was to investigate the relationship between proAKAP4 concentration with horse sperm motility descriptors and spermatic motile subpopulations. For this purpose, a total of 48 ejaculates from 13 different stallions were analyzed. Spermatic motility descriptors were obtained by the CASA system, and four motile subpopulations (SP) with specific motility patterns were statistically identified. ProAKAP4 concentrations were evaluated by ELISA. The relationship between motility descriptors of sperm subpopulations and proAKAP4 concentrations was evaluated. Following a hierarchical cluster statistical analysis, ejaculates were divided into two groups according to their proAKAP4 concentrations, either having low proAKAP4 concentrations (5.06−35.61 ng/10M spz; n = 23) or high (39.92−82.23 ng/10M spz; n = 25) proAKAP4 concentrations (p < 0.001). ProAKAP4 concentrations were positively correlated (p < 0.05) with total and progressive motility, as well as with parameters of velocity. ProAKAP4 amount also showed a negative correlation (p < 0.05) with sperm motile subpopulation number 3, which was the subpopulation with the lowest velocity parameters. In conclusion, proAKAP4 concentration in stallion semen positively reflects sperm progressive motility with the functional velocity kinematic descriptors. Concentrations of proAKAP4 higher than 37.77 ng/10M spz were correlated with a very good quality frozen/thawed stallion semen.
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Carracedo S, Briand-Amirat L, Dordas-Perpinyà M, Ramos Escuredo Y, Delcombel R, Sergeant N, Delehedde M. ProAKAP4 protein marker: Towards a functional approach to male fertility. Anim Reprod Sci 2022; 247:107074. [DOI: 10.1016/j.anireprosci.2022.107074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/16/2022] [Accepted: 09/20/2022] [Indexed: 11/01/2022]
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Dordas-Perpinyà M, Sergeant N, Ruelle I, Bruyas JF, Charreaux F, Michaud S, Carracedo S, Catalán J, Miró J, Delehedde M, Briand-Amirat L. ProAKAP4 Semen Concentrations as a Valuable Marker Protein of Post-Thawed Semen Quality and Bull Fertility: A Retrospective Study. Vet Sci 2022; 9:224. [PMID: 35622752 PMCID: PMC9144616 DOI: 10.3390/vetsci9050224] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/29/2022] [Accepted: 04/30/2022] [Indexed: 02/04/2023] Open
Abstract
Functional sperm quality markers to predict bull fertility have been actively investigated. Among them, proAKAP4, which is the precursor of AKAP4, the main structural protein in the fibrous sheath of spermatozoa; appears to be promising, especially since spermatozoa lacking AKAP4 expression were shown to be immotile, abnormal, and infertile. In this study, the objective was to evaluate proAKAP4 concentration values with the classic sperm motility descriptors and fertility outcomes (NRR at 90 days) in post-thawed conditions of 10 bulls' semen. ProAKAP4 expression was confirmed by Western blotting and proAKAP4 concentrations were determined by ELISA. Variations in proAKAP4 concentrations were observed independently of the motility sperm descriptors measured using computer-assisted semen analysis (CASA). A ProAKAP4 concentration of 38.67 ± 8.55 ng/10 million spermatozoa was obtained as a statistical mean of all samples. Threshold values of proAKAP4 were then determined between 19.96 to 96.95 ng/10 million spermatozoa. ProAKAP4 concentrations were positively correlated with progressive motility and the linearity coefficient. The sperm showing the lowest progressive motility were the samples exhibiting proAKAP4 concentrations below 20 ng/10 million spermatozoa. Furthermore, proAKAP4 concentrations were significantly higher in bulls with a higher NRR in the field. Our results demonstrate a correlation between the semen concentration of proAKAP4 and NRR-90d (p = 0.05) in post-thawed bull semen, highlighting the potential of proAKAP4 as a predictive marker of bull fertility.
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Affiliation(s)
- Marta Dordas-Perpinyà
- Oniris, Nantes-Atlantic College of Veterinary Medicine, 44300 Nantes, France; (M.D.-P.); (I.R.); (J.-F.B.); (S.M.)
- Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, 08193 Cerdanyola del Vallès, Spain; (J.C.); (J.M.)
| | - Nicolas Sergeant
- U1172 LilNCog—Lille Neuroscience & Cognition, CHU Lille, Inserm, University Lille, 59000 Lille, France;
- SPQI S.A.S, 82 rue Jeanne d’Arc, 59000 Lille, France; (S.C.); (M.D.)
| | - Isabelle Ruelle
- Oniris, Nantes-Atlantic College of Veterinary Medicine, 44300 Nantes, France; (M.D.-P.); (I.R.); (J.-F.B.); (S.M.)
| | - Jean-François Bruyas
- Oniris, Nantes-Atlantic College of Veterinary Medicine, 44300 Nantes, France; (M.D.-P.); (I.R.); (J.-F.B.); (S.M.)
| | | | - Sandrine Michaud
- Oniris, Nantes-Atlantic College of Veterinary Medicine, 44300 Nantes, France; (M.D.-P.); (I.R.); (J.-F.B.); (S.M.)
| | - Sara Carracedo
- SPQI S.A.S, 82 rue Jeanne d’Arc, 59000 Lille, France; (S.C.); (M.D.)
| | - Jaime Catalán
- Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, 08193 Cerdanyola del Vallès, Spain; (J.C.); (J.M.)
| | - Jordi Miró
- Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, 08193 Cerdanyola del Vallès, Spain; (J.C.); (J.M.)
| | - Maryse Delehedde
- SPQI S.A.S, 82 rue Jeanne d’Arc, 59000 Lille, France; (S.C.); (M.D.)
| | - Lamia Briand-Amirat
- Oniris, Nantes-Atlantic College of Veterinary Medicine, 44300 Nantes, France; (M.D.-P.); (I.R.); (J.-F.B.); (S.M.)
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Dey S, Brothag C, Vijayaraghavan S. Signaling Enzymes Required for Sperm Maturation and Fertilization in Mammals. Front Cell Dev Biol 2019; 7:341. [PMID: 31921853 PMCID: PMC6930163 DOI: 10.3389/fcell.2019.00341] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 12/03/2019] [Indexed: 12/18/2022] Open
Abstract
In mammals, motility and fertilizing ability of spermatozoa develop during their passage through the epididymis. After ejaculation, sperm undergo capacitation and hyperactivation in the female reproductive tract - a motility transition that is required for sperm penetration of the egg. Both epididymal initiation of sperm motility and hyperactivation are essential for male fertility. Motility initiation in the epididymis and sperm hyperactivation involve changes in metabolism, cAMP (cyclic adenosine mono-phosphate), calcium and pH acting through protein kinases and phosphatases. Despite this knowledge, we still do not understand, in biochemical terms, how sperm acquire motility in the epididymis and how motility is altered in the female reproductive tract. Recent data show that the sperm specific protein phosphatase PP1γ2, glycogen synthase kinase 3 (GSK3), and the calcium regulated phosphatase calcineurin (PP2B), are involved in epididymal sperm maturation. The protein phosphatase PP1γ2 is present only in testis and sperm in mammals. PP1γ2 has a isoform-specific requirement for normal function of mammalian sperm. Sperm PP1γ2 is regulated by three proteins - inhibitor 2, inhibitor 3 and SDS22. Changes in phosphorylation of these three inhibitors and their binding to PP1γ2 are involved in initiation and activation of sperm motility. The inhibitors are phosphorylated by protein kinases, one of which is GSK3. The isoform GSK3α is essential for epididymal sperm maturation and fertility. Calcium levels dramatically decrease during sperm maturation and initiation of motility suggesting that the calcium activated sperm phosphatase (PP2B) activity also decreases. Loss of PP2B results in male infertility due to impaired sperm maturation in the epididymis. Thus the three signaling enzymes PP1γ2, GSK3, and PP2B along with the documented PKA (protein kinase A) have key roles in sperm maturation and hyperactivation. Significantly, all these four signaling enzymes are present as specific isoforms only in placental mammals, a testimony to their essential roles in the unique aspects of sperm function in mammals. These findings should lead to a better biochemical understanding of the basis of male infertility and should lead to novel approaches to a male contraception and managed reproduction.
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9
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Blommaert D, Sergeant N, Delehedde M, Jouy N, Mitchell V, Franck T, Donnay I, Lejeune J, Serteyn D. Expression, localization, and concentration of A-kinase anchor protein 4 (AKAP4) and its precursor (proAKAP4) in equine semen: Promising marker correlated to the total and progressive motility in thawed spermatozoa. Theriogenology 2019; 131:52-60. [DOI: 10.1016/j.theriogenology.2019.03.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 03/13/2019] [Accepted: 03/18/2019] [Indexed: 12/13/2022]
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10
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Nixon B, Bernstein IR, Cafe SL, Delehedde M, Sergeant N, Anderson AL, Trigg NA, Eamens AL, Lord T, Dun MD, De Iuliis GN, Bromfield EG. A Kinase Anchor Protein 4 Is Vulnerable to Oxidative Adduction in Male Germ Cells. Front Cell Dev Biol 2019; 7:319. [PMID: 31921838 PMCID: PMC6933317 DOI: 10.3389/fcell.2019.00319] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 11/20/2019] [Indexed: 12/16/2022] Open
Abstract
Oxidative stress is a leading causative agent in the defective sperm function associated with male infertility. Such stress commonly manifests via the accumulation of pathological levels of the electrophilic aldehyde, 4-hydroxynonenal (4HNE), generated as a result of lipid peroxidation. This highly reactive lipid aldehyde elicits a spectrum of cytotoxic lesions owing to its propensity to form stable adducts with biomolecules. Notably however, not all elements of the sperm proteome appear to display an equivalent vulnerability to 4HNE modification, with only a small number of putative targets having been identified to date. Here, we validate one such target of 4HNE adduction, A-Kinase Anchor Protein 4 (AKAP4); a major component of the sperm fibrous sheath responsible for regulating the signal transduction and metabolic pathways that support sperm motility and capacitation. Our data confirm that both the precursor (proAKAP4), and mature form of AKAP4, are conserved targets of 4HNE adduction in primary cultures of post-meiotic male germ cells (round spermatids) and in mature mouse and human spermatozoa. We further demonstrate that 4HNE treatment of round spermatids and mature spermatozoa results in a substantial reduction in the levels of both proAKAP4 and AKAP4 proteins. This response proved refractory to pharmacological inhibition of proteolysis, but coincided with an apparent increase in the degree of protein aggregation. Further, we demonstrate that 4HNE-mediated protein degradation and/or aggregation culminates in reduced levels of capacitation-associated phosphorylation in mature human spermatozoa, possibly due to dysregulation of the signaling framework assembled around the AKAP4 scaffold. Together, these findings suggest that AKAP4 plays an important role in the pathophysiological responses to 4HNE, thus strengthening the importance of AKAP4 as a biomarker of sperm quality, and providing the impetus for the design of an efficacious antioxidant-based intervention strategy to alleviate sperm dysfunction.
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Affiliation(s)
- Brett Nixon
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- *Correspondence: Brett Nixon,
| | - Ilana R. Bernstein
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Shenae L. Cafe
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | | | - Nicolas Sergeant
- SPQI – 4BioDx-Breeding Section, Lille, France
- University of Lille, INSERM UMRS, Lille, France
| | - Amanda L. Anderson
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Natalie A. Trigg
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Andrew L. Eamens
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Tessa Lord
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Matthew D. Dun
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia
- Priority Research Centre for Cancer Research Innovation and Translation, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Geoffry N. De Iuliis
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - Elizabeth G. Bromfield
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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11
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Jumeau F, Sigala J, Dossou-Gbete F, Frimat K, Barbotin AL, Buée L, Béhal H, Sergeant N, Mitchell V. A-kinase anchor protein 4 precursor (pro-AKAP4) in human spermatozoa. Andrology 2018; 6:854-859. [DOI: 10.1111/andr.12524] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 06/11/2018] [Accepted: 06/14/2018] [Indexed: 12/14/2022]
Affiliation(s)
- F. Jumeau
- EA 4308 - GQG - Gametogenesis and Gamete Quality; University of Lille; Lille France
- CHU Lille; Reproductive Biology - Spermiology - CECOS Institute; Lille France
- INSERM, UMR-S 1172, Alzheimer & Tauopathies; CHU Lille; University of Lille; Lille France
| | - J. Sigala
- EA 4308 - GQG - Gametogenesis and Gamete Quality; University of Lille; Lille France
- CHU Lille; Reproductive Biology - Spermiology - CECOS Institute; Lille France
- INSERM, UMR-S 1172, Alzheimer & Tauopathies; CHU Lille; University of Lille; Lille France
| | - F. Dossou-Gbete
- EA 4308 - GQG - Gametogenesis and Gamete Quality; University of Lille; Lille France
- CHU Lille; Reproductive Biology - Spermiology - CECOS Institute; Lille France
- INSERM, UMR-S 1172, Alzheimer & Tauopathies; CHU Lille; University of Lille; Lille France
| | - K. Frimat
- EA 4308 - GQG - Gametogenesis and Gamete Quality; University of Lille; Lille France
- INSERM, UMR-S 1172, Alzheimer & Tauopathies; CHU Lille; University of Lille; Lille France
| | - A. L. Barbotin
- EA 4308 - GQG - Gametogenesis and Gamete Quality; University of Lille; Lille France
- CHU Lille; Reproductive Biology - Spermiology - CECOS Institute; Lille France
| | - L. Buée
- INSERM, UMR-S 1172, Alzheimer & Tauopathies; CHU Lille; University of Lille; Lille France
| | - H. Béhal
- CHU Lille; EA 2694 - Santé Publique: Épidémiologie et Qualité des Soins; University of Lille; Lille France
| | - N. Sergeant
- INSERM, UMR-S 1172, Alzheimer & Tauopathies; CHU Lille; University of Lille; Lille France
| | - V. Mitchell
- EA 4308 - GQG - Gametogenesis and Gamete Quality; University of Lille; Lille France
- CHU Lille; Reproductive Biology - Spermiology - CECOS Institute; Lille France
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12
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Naresh S, Atreja SK. The protein tyrosine phosphorylation during in vitro capacitation and cryopreservation of mammalian spermatozoa. Cryobiology 2015; 70:211-6. [PMID: 25828199 DOI: 10.1016/j.cryobiol.2015.03.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 03/07/2015] [Accepted: 03/21/2015] [Indexed: 11/26/2022]
Abstract
Before the process of fertilization, spermatozoa necessitate a period of residence in the female reproductive environment, and undergo a sequence of physiological and biochemical changes collectively referred to as capacitation. Accumulated evidences from several laboratories indicated that the protein tyrosine phosphorylation (PTP) is one of the most important intracellular signaling events regulating sperm function, and is a meaningful indicator of capacitation. Different factors that affect PTP are cholesterol efflux, influx of HCO3(-), increased intracellular Ca(2+), cAMP and reactive oxygen species (ROS). cAMP/PKA and extracellular signal regulated kinases (ERKs) are the known important signaling pathways primarily involved in PTP. Advanced proteomics approaches have revealed several proteins that undergo tyrosine phosphorylation during capacitation. Semen cryopreservation subjects spermatozoa to frequent stressors, which result in capacitation like changes (cryo-capacitation). The cryo-capacitated spermatozoa usually show different patterns of PTP than the normal in vitro capacitated spermatozoa. In the current manuscript, we have summarized some information about the proteins undergoing tyrosine phosphorylation during capacitation and the effect of cryopreservation on PTP as well as the possibilities to reduce the changes associated with cryopreservation process.
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Affiliation(s)
- Sai Naresh
- Reproductive Biochemistry Laboratory, Animal Biochemistry Division, National Dairy Research Institute, Karnal, Haryana 132001, India.
| | - Suresh Kumar Atreja
- Reproductive Biochemistry Laboratory, Animal Biochemistry Division, National Dairy Research Institute, Karnal, Haryana 132001, India.
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13
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Affiliation(s)
- Regina M Turner
- Department of Clinical Studies, Center for Animal Transgenesis, Germ Cell Research, University of Pennsylvania School of Veterinary Medicine, Kennett Square, USA
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14
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Identification of capacitation associated tyrosine phosphoproteins in buffalo (Bubalus bubalis) and cattle spermatozoa. Anim Reprod Sci 2011; 123:40-7. [DOI: 10.1016/j.anireprosci.2010.11.013] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 10/28/2010] [Accepted: 11/25/2010] [Indexed: 11/22/2022]
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15
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Gyamera-Acheampong C, Vasilescu J, Figeys D, Mbikay M. PCSK4-null sperm display enhanced protein tyrosine phosphorylation and ADAM2 proteolytic processing during in vitro capacitation. Fertil Steril 2009; 93:1112-23. [PMID: 19342015 DOI: 10.1016/j.fertnstert.2008.12.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 10/31/2008] [Accepted: 12/10/2008] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To study the molecular basis for the accelerated capacitation rate in PCSK4-null sperm. DESIGN Comparative and controlled experimental research study. SETTING Academic medical institute. ANIMAL(S) Male mice C57BL/6J wild-type or null congenics for the Pcsk4 allele. INTERVENTION(S) Cauda and epididymal sperm were capacitated for varying times. MAIN OUTCOME MEASURE(S) Differences in sperm protein tyrosine phosphorylation and proteolytic processing of sperm-egg ligands ADAM2 and ADAM3. RESULT(S) The PCSK4-null sperm proteins are hyper-tyrosine phosphorylated during capacitation. This hyperphosphorylation is dependent on protein kinase A (PKA), albumin, and calcium. There is also more ADAM2 proteolytic processing from a 46-kDa form of ADAM2 to a 27-kDa form in PCSK4-null sperm than in wild-type sperm. This processing is dependent on cholesterol efflux. CONCLUSION(S) Lack of PCSK4 is associated with quantitative changes in the phosphorylation and proteolysis of sperm proteins during capacitation; therefore, alterations in signal transduction and proteolytic processing during capacitation may underlie the fertilization incompetence of PCSK4-null sperm. More investigation is needed to determine how and to what extent these changes might contribute to the loss of fertilizing ability of PCSK4-null sperm.
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16
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Hui L, Lu J, Han Y, Pilder SH. The Mouse t Complex Gene Tsga2, Encoding Polypeptides Located in the Sperm Tail and Anterior Acrosome, Maps to a Locus Associated with Sperm Motility and Sperm-Egg Interaction Abnormalities1. Biol Reprod 2006; 74:633-43. [PMID: 16354795 DOI: 10.1095/biolreprod.105.045963] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Previous studies of sperm from mice heterozygous for a t haplotype (t) and heterospecific combinations of the t complex identified two tightly linked genetic factors responsible for t/t male sterility related to expression of the flagellar waveform aberration, curlicue. Dnahc8, an axonemal dynein heavy chain gene, is a strong candidate for the proximal factor, Ccua, but the identity of the distal factor, Ccub, is unknown. In the present study, we employ motility assays of sperm from males heterozygous for t and novel heterospecific combinations of the t complex to demonstrate that Ccub is a composite of at least two synergic elements, Ccub1, positioned within a genomic interval spanning approximately 0.6 Mb immediately distal to Dnahc8, and Ccub2, situated in a region approximately 4-7 Mb distal to Ccub1. We also show that Tsga2, a testis-restricted gene, fulfills many of the prerequisites required to make it a strong candidate for Ccub1. These include: 1) its location within the aforementioned genomic interval; 2) a highly reduced level of testis expression by its heterospecific allele relative to the level of expression of its t allele; 3) determination that TSGA2(t) carries numerous nonsynonymous mutations in residues otherwise highly conserved in all known orthologous proteins; 4) the detection of major TSGA2 polypeptides in sperm protein extracts; and 5) the apparent distribution of these polypeptides in major sperm tail structures. Surprisingly, these TSGA2 isoforms appear to localize in the vicinity of the anterior acrosome, as well, suggesting that Tsga2 may also play a role in sperm-egg interaction. Finally, our results indicate that a TSGA2 polypeptide with apparent similarities to the smaller of the two sperm isoforms is expressed by epididymal cells.
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Affiliation(s)
- Ling Hui
- Temple University School of Medicine, Department of Anatomy and Cell Biology, Philadelphia, Pennsylvania 19140, USA
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17
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Turner RM. Moving to the beat: a review of mammalian sperm motility regulation. Reprod Fertil Dev 2006; 18:25-38. [PMID: 16478600 DOI: 10.1071/rd05120] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Accepted: 01/21/2005] [Indexed: 01/18/2023] Open
Abstract
Because it is generally accepted that a high percentage of poorly motile or immotile sperm will adversely affect male fertility, analysis of sperm motility is a central part of the evaluation of male fertility. In spite of its importance to fertility, poor sperm motility remains only a description of a pathology whose underlying cause is typically poorly understood. The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology.
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Affiliation(s)
- Regina M Turner
- Department of Clinical Studies, Center for Animal Transgenesis and Germ Cell Research, University of Pennsylvania School of Veterinary Medicine, New Bolton Center, Kennett Square, PA 19348, USA.
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18
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Turner RMO, Casas-Dolz R, Schlingmann KL, Hameed S. Characterization of an A-kinase anchor protein in equine spermatozoa and examination of the effect of semen cooling and cryopreservation on the binding of that protein to the regulatory subunit of protein kinase-A. Am J Vet Res 2005; 66:1056-64. [PMID: 16008231 DOI: 10.2460/ajvr.2005.66.1056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine whether a homologue of A-kinase anchor protein 4 (AKAP4) is present and functional as an AKAP in equine spermatozoa and examine the effect of semen cooling and cryopreservation on binding of equine AKAP4 to the regulatory (RII) subunit of protein kinase-A (PK-A). SAMPLE POPULATION Ejaculated semen collected from 2 fertile stallions, 3 bulls, and 3 humans. PROCEDURE Identification of an equine homologue of AKAP4 was investigated via DNA sequencing. Protein was extracted from the spermatozoa of each species for immunoblot analysis to identify AKAP4 and its precursor protein, pro-AKAP4; immunofluorescence microscopy was used to localize those proteins in spermatozoa. Ligand overlay assays were used to determine whether the identified proteins bound to the RII subunit of PK-A and whether cooling or cryopreservation of spermatozoa affected that binding. RESULTS The partial genomic sequence of AKAP4 was identified in equine spermatozoa, and immunoblot analysis confirmed that AKAP4 and pro-AKAP4 are present in equine spermatozoa. Via immunofluorescence microscopy, these proteins were localized to the spermatozoal principal piece. Results of ligand overlay assays indicated that equine AKAP4 and pro-AKAP4 bind to the RII subunit of PK-A and are AKAPs; AKAP4-RII binding was not affected by cooling or cryopreservation of spermatozoa. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that equine AKAP4 anchors PK-A to the spermatozoal flagellum (where the kinase is likely to be required for the regulation of spermatozoal motility), but decreases in spermatozoal motility in cooled or cryopreserved semen are not associated with decreased binding of AKAP4 and PK-A.
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Affiliation(s)
- Regina M O Turner
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348-1692, USA
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19
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Naz RK, Rajesh PB. Role of tyrosine phosphorylation in sperm capacitation / acrosome reaction. Reprod Biol Endocrinol 2004; 2:75. [PMID: 15535886 PMCID: PMC533862 DOI: 10.1186/1477-7827-2-75] [Citation(s) in RCA: 192] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Accepted: 11/09/2004] [Indexed: 11/10/2022] Open
Abstract
Capacitation is an important physiological pre-requisite before the sperm cell can acrosome react and fertilize the oocyte. Recent reports from several laboratories have amply documented that the protein phosphorylation especially at tyrosine residues is one of the most important events that occur during capacitation. In this article, we have reviewed the data from our and other laboratories, and have constructed a heuristic model for the mechanisms and molecules involved in capacitation/acrosome reaction.
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Affiliation(s)
- Rajesh K Naz
- Division of Research, Department of Obstetrics and Gynecology, Medical College of Ohio, Toledo, Ohio, USA
| | - Preeti B Rajesh
- Division of Research, Department of Obstetrics and Gynecology, Medical College of Ohio, Toledo, Ohio, USA
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20
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Luconi M, Carloni V, Marra F, Ferruzzi P, Forti G, Baldi E. Increased phosphorylation of AKAP by inhibition of phosphatidylinositol 3-kinase enhances human sperm motility through tail recruitment of protein kinase A. J Cell Sci 2004; 117:1235-46. [PMID: 14996943 DOI: 10.1242/jcs.00931] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sperm motility is regulated by a complex balance between kinases and phosphatases. Among them, phosphatidylinositol 3-kinase (PI 3-kinase) has been recently suggested to negatively regulate sperm motility (Luconi, M., Marra, F., Gandini, L., Lenzi, A., Filimberti, E., Forti, G. and Baldi, E. (2001). Hum. Reprod. 16, 1931-1937). We demonstrate the presence and activity of PI 3-kinase in human spermatozoa and have investigated the molecular mechanism(s) by which the PI 3-kinase inhibitor, LY294002, triggers an increase in sperm motility. PI 3-kinase inhibition results in an increase in intracellular cAMP levels and in tyrosine phosphorylation of the protein kinase A-anchoring protein AKAP3. These effects finally result in a stimulation of protein kinase A (PKA) binding to AKAP3 in sperm tails through the regulatory subunit RIIβ. The increased binding of RIIβ to AKAP3 induced by LY294002 is mainly due to tyrosine phosphorylation of AKAP3, since it is completely blocked by the tyrosine kinase inhibitor erbstatin, which also reverses the effects of LY294002 on motility and suppresses PKA-AKAP3 interaction. The requirement of PKA binding to AKAP3 for sperm motility is confirmed by the reduction of motility induced by an inhibitor of RIIβ-AKAP3 binding, Ht31, whose effects on sperm motility and PKA binding to AKAP3 are reversed by LY294002.
These results demonstrate that PI 3-kinase negatively regulates sperm motility by interfering with AKAP3-PKA binding, providing the first evidence of a molecular mechanism by which PKA can be targeted to sperm tails by interaction with tyrosine phosphorylated form of AKAP3.
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Affiliation(s)
- Michaela Luconi
- Andrology Unit, Department of Physiopathology, University of Florence, Viale Pieraccini 6, I-50139 Florence, Italy.
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21
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Modarressi MH, Behnam B, Cheng M, Taylor KE, Wolfe J, van der Hoorn FA. Tsga10 encodes a 65-kilodalton protein that is processed to the 27-kilodalton fibrous sheath protein. Biol Reprod 2003; 70:608-15. [PMID: 14585816 PMCID: PMC3158800 DOI: 10.1095/biolreprod.103.021170] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
We had previously reported the isolation of the testis-specific human gene Tsga10, which is not expressed in testes from two infertile patients. To study its role and function, we cloned the mouse homologue Mtsga10. Mtsga10 localizes to mouse chromosome 1, band B. This region is syntenic with human chromosome 2q11.2, where Tsga10 is located. We demonstrate that Mtsga10 mRNA is expressed in testis, but not in other adult tissues, and in several human fetal tissues and primary tumors. We uncovered that different species use different first exons and, consequently, different promoters. Using several antibodies, we discovered that, in mouse testis, Mtsga10 encodes a 65-kDa spermatid protein that appears to be processed to a 27-kDa protein of the fibrous sheath, a major sperm tail structure, in mature spermatozoa. Mtsga10 protein contains a putative myosin/Ezrin/radixin/moesin (ERM) domain. Transfection of fibroblasts with GFP-Mtsga10 fusion protein results in formation of short, thick filaments and deletion of the myosin/ERM domain abolished filament formation. Our results suggest the possibility that Tsga10 plays a role in the sperm tail fibrous sheath.
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Affiliation(s)
- Mohammad H. Modarressi
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Canada T2N 4N1
| | - Babak Behnam
- Biology Department, University College London, London, United Kingdom
| | - Min Cheng
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Canada T2N 4N1
| | - Kay E. Taylor
- Biology Department, University College London, London, United Kingdom
| | - Jonathan Wolfe
- Biology Department, University College London, London, United Kingdom
| | - Frans A. van der Hoorn
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Canada T2N 4N1
- Correspondence: Frans A. van der Hoorn, Department of Biochemistry & Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1. FAX: 403 283 8727;
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Ullas KS, Rao MRS. Phosphorylation of rat spermatidal protein TP2 by sperm-specific protein kinase A and modulation of its transport into the haploid nucleus. J Biol Chem 2003; 278:52673-80. [PMID: 14514679 DOI: 10.1074/jbc.m308365200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transition protein 2 (TP2), which is expressed during stages 12-15 of mammalian spermiogenesis, has been shown to undergo phosphorylation immediately after its synthesis. We reported earlier that TP2 is phosphorylated in vitro at threonine 101 and serine 109 by the salt extract of sonication-resistant (elongating and elongated) spermatid nuclei and the protein kinase phosphorylating TP2 was identified to be protein kinase A (PKA). We now report that the cytosol from haploid spermatids but not from premeiotic germ cells is able to phosphorylate recombinant TP2 in vitro at threonine 101 and serine 109. The kinase present in the haploid spermatid cytosol that phosphorylates TP2 has been identified to be the sperm-specific isoform of protein kinase A (Cs-PKA). Reverse transcription-PCR analysis indicated that Cs-PKA was present in the haploid spermatids and absent from premeiotic germ cells. The rat Cs-PKA transcript was amplified and sequenced using the isoform-specific primers. The sequence of rat Cs-PKA at the N terminus differs from mouse and human by one amino acid. Western blot analysis using specific anti-Calpha1 antibodies revealed that Calpha1-PKA is absent in haploid spermatid cytosol. We have also established an in vitro nuclear transport assay for the haploid round spermatids. Using this assay, we have found that the cytoplasmic factors and ATP are absolutely essential for translocation of TP2 into the nucleus. Phosphorylation was found to positively modulate the NLS dependent import of TP2 into the nucleus.
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Affiliation(s)
- Kolthur S Ullas
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
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23
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Pommer AC, Rutllant J, Meyers SA. Phosphorylation of protein tyrosine residues in fresh and cryopreserved stallion spermatozoa under capacitating conditions. Biol Reprod 2003; 68:1208-14. [PMID: 12606471 DOI: 10.1095/biolreprod.102.011106] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Phosphorylation of tyrosine residues on sperm proteins is one important intracellular mechanism regulating sperm function that may be a meaningful indicator of capacitation. There is substantial evidence that cryopreservation promotes the capacitation of sperm and this cryocapacitation is frequently cited as one factor associated with the reduced longevity of cryopreserved sperm in the female reproductive tract. This study was designed to determine whether stallion sperm express different levels of tyrosine phosphorylation after in vitro capacitation and whether thawed sperm display similar phosphorylation characteristics in comparison with freshly ejaculated sperm. Experiments were performed to facilitate comparisons of tyrosine phosphorylation, motility, and viability of sperm prior to and following in vitro capacitation in fresh and frozen-thawed sperm. We hypothesized that equine spermatozoa undergo tyrosine phosphorylation during capacitation and that this phosphorylation is modified when sperm have been cryopreserved. We also hypothesized that tyrosine phosphorylation could be enhanced by the use of the activators dibutyryl cAMP (db cAMP) and caffeine, as well as methyl beta-cyclodextrin-which causes cholesterol efflux from the spermatozoa-and inhibited by the protein kinase A (PK-A) inhibitor H-89. Our results indicate that equine sperm capacitation is mediated by a signaling pathway that involves cAMP-dependent PK-A and tyrosine kinases and that cryopreserved sperm may be more sensitive to inducers of capacitation, which could explain their limited life span when compared with fresh sperm.
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Affiliation(s)
- Angela C Pommer
- School of Veterinary Medicine, Department of Anatomy, Physiology, and Cell Biology, University of California, Davis, California 95616, USA
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24
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Patil SB, Kulanand J, Padma P, Shivaji S. Reactivation of motility of demembranated hamster spermatozoa: role of protein tyrosine kinase and protein phosphatases. Andrologia 2002; 34:74-86. [PMID: 11966573 DOI: 10.1046/j.0303-4569.2001.00474.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Demembranated cauda epididymidal spermatozoa of hamster, following reactivation with 1 mm ATP, exhibited either a loop or planar type of motility. The spermatozoa with planar motility exhibited increased progressive velocity (VSL), straightness (STR), linearity (LIN) and beat cross frequency (BCF) compared to the spermatozoa with loop type motility. cAMP was observed to have differential effects on the motility parameters of the demembranated spermatozoa depending on the type of motility. For instance, in the loop type, average path velocity (VAP), curvilinear velocity (VCL) and VSL were increased in the presence of cAMP unlike in the planar type. Furthermore, in an attempt to understand the role of protein kinases and protein phosphatases in regulation of sperm motility, the effects of various inhibitors of these enzymes on the motility and phosphorylation of proteins of reactivated demembranated spermatozoa were studied. Inhibitors of PTKase (protein tyrosine kinase) and protein phosphatases inhibited the motility of reactivated demembranated hamster spermatozoa. The activity of the respective enzymes associated with demembranated spermatozoa was concurrently inhibited, thus providing evidence that the effect of the inhibitors on motility was mediated through their inhibitory effects on the activities of the enzymes. The results also demonstrated that two phosphotyrosinylated proteins of molecular weight 65 and 80 kDa showed reduced phosphorylation in the presence of PTKase inhibitors, thus indicating their possible role in reactivation of motility of demembranated hamster spermatozoa.
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Affiliation(s)
- S B Patil
- Centre for Cellular and Molecular Biology, Hyderabad, India
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25
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Jha KN, Shivaji S. Identification of the major tyrosine phosphorylated protein of capacitated hamster spermatozoa as a homologue of mammalian sperm a kinase anchoring protein. Mol Reprod Dev 2002; 61:258-70. [PMID: 11803562 DOI: 10.1002/mrd.1155] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The molecular basis of mammalian sperm capacitation is unique in that, it is associated with a protein kinase A (PKA) dependent upregulation of protein tyrosine phosphorylation. Therefore, PKA activity during capacitation would be crucial for the downstream events of protein tyrosine phosphorylation, and mechanisms may exist to ensure that PKA phosphorylates its specific substrate. This could be achieved by bringing PKA close to its substrate, a function normally carried out by an A-kinase anchoring protein (AKAP). We showed previously that cauda epididymidal spermatozoa of hamster undergo a capacitation-dependent increase in protein tyrosine phosphorylation. In the present study, evidence is provided that two major tyrosine phosphorylated proteins of molecular weight 97 and 83 kDa are the hamster homologues of mouse pro-AKAP82 and AKAP82, and have been designated as hamster pro-AKAP83 and AKAP83 respectively. Hamster AKAP83 resembled the mouse AKAP82 with respect to its molecular weight, pI (pH 5-5.5) and cDNA and amino acid sequences. Sequence analysis indicated that the primary structure of pro-AKAP83 was highly conserved and exhibited 91% identity with mouse and rat AKAP82. Further, the functional domains, namely the region involved in binding the regulatory subunit of PKA and the proteolytic cleavage site between pro-AKAP83 and AKAP83, were identical with that observed in rat and mouse pro-AKAP82 and AKAP82. Immunoblot analysis using polyclonal hamster anti-AKAP83 antibodies indicated that AKAP83 was present both in caput and cauda epididymidal spermatozoa. The antibody also identified the pro-AKAP82 and AKAP82 in mouse caput and cauda epididymidal spermatozoa. Immunofluorescence studies indicated that AKAP83 in hamster spermatozoa was localized along the length of principal piece of the tail. It was also demonstrated that hamster pro-AKAP83/AKAP83 gene expression was testis specific and was not expressed in other organs in either sex. This is the first report implicating AKAP in capacitation in rodents.
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Affiliation(s)
- Kula Nand Jha
- Centre for Cellular and Molecular Biology, Hyderabad, India
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26
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Abstract
Over the past few years, significant progress has been made in characterizing the expression and localization of proteins that act as scaffolds for cAMP-dependent protein kinase (PK-A). These A-kinase anchor proteins (AKAPs) tether PK-A to intracellular organelles and structures, sequestering the kinase near its physiological substrates. The compartmentalization of distinct pockets of PK-A activity serves to provide spatial regulation of this signaling pathway. In addition, other signaling proteins bind to AKAPs, as do some newly described proteins of unknown function, suggesting that proteins of various pathways are anchored through AKAPs.
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Affiliation(s)
- S B Moss
- Center for Research on Reproduction and Women's Health, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA.
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27
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Visconti PE, Hao Z, Purdon MA, Stein P, Balsara BR, Testa JR, Herr JC, Moss SB, Kopf GS. Cloning and chromosomal localization of a gene encoding a novel serine/threonine kinase belonging to the subfamily of testis-specific kinases. Genomics 2001; 77:163-70. [PMID: 11597141 DOI: 10.1006/geno.2001.6628] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Using reverse transcription-polymerase chain reaction (RT-PCR) with degenerate oligonucleotides corresponding to two highly conserved motifs within the protein kinase family of catalytic domains, we isolated a PCR fragment encoding a novel member of the testis-specific serine/threonine kinases (STK) from mouse male mixed germ cell mRNA. This PCR fragment recognized a 1020-bp transcript in male germ cells by northern blot analysis and was used to clone a full-length cDNA from a mouse mixed germ cell cDNA library. This cDNA has an open reading frame of 804 bases encoding a protein of 268 amino acids. This novel gene is almost identical to Stk22c, encoding a recently described testis-specific protein kinase, except for base-pair deletions that result in a shift in the coding region and an alteration of 22 amino acids (residues 109-131). Due to its homology with Stk22c, we have called this protein kinase gene Stk22d. Northern blot analysis revealed that this protein kinase is developmentally expressed in testicular germ cells and is not present in brain, ovary, kidney, liver, or early embryonic cells. We then cloned the human homologue of this protein kinase gene (STK22C) and found it to be expressed exclusively in the testis. Fluorescence in situ hybridization with both the human and mouse cDNA clones revealed syntenic localization on chromosomes 1p34-p35 and 4E1, respectively.
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Affiliation(s)
- P E Visconti
- Center for Research on Reproduction & Women's Health, University of Pennsylvania, Philadelphia, Pennsylvania, 19104-6142, USA
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28
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San Agustin JT, Witman GB. Differential expression of the C(s) and Calpha1 isoforms of the catalytic subunit of cyclic 3',5'-adenosine monophosphate-dependent protein kinase testicular cells. Biol Reprod 2001; 65:151-64. [PMID: 11420235 DOI: 10.1095/biolreprod65.1.151] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The amino terminus of the sperm cAMP-dependent protein kinase catalytic subunit (termed C(s)) differs from that of the Calpha1 isoform expressed in most tissues due to the use of alternative transcripts of the Calpha gene. Both Calpha1 and C(s) transcripts are present in testis; C(s) is expressed specifically in spermatogenic cells and is the only C isoform detected in mature sperm. Immunohistochemistry of mouse testis using antibodies specific for C(s) and Calpha1 now shows that Calpha1 is present in somatic testicular cells, spermatogonia, and preleptotene spermatocytes but not in cells that are in later stages of spermatogenesis. In contrast, C(s) is expressed only in midpachytene and later stage spermatocytes and in spermatids. Therefore, C(s) and Calpha1 expression do not overlap. Immunofluorescence microscopic localization of C(s) in murine and ovine sperm reveals that C(s) is located primarily in sperm tail components, including the midpiece mitochondria and the axoneme. Quantitative analysis of Western blots indicates that individual ovine sperm contain approximately 4 x 10(5) molecules of C(s), a seemingly large number for a protein that acts catalytically.
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Affiliation(s)
- J T San Agustin
- Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
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29
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Gaillard AR, Diener DR, Rosenbaum JL, Sale WS. Flagellar radial spoke protein 3 is an A-kinase anchoring protein (AKAP). J Cell Biol 2001; 153:443-8. [PMID: 11309423 PMCID: PMC2169452 DOI: 10.1083/jcb.153.2.443] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previous physiological and pharmacological experiments have demonstrated that the Chlamydomonas flagellar axoneme contains a cAMP-dependent protein kinase (PKA) that regulates axonemal motility and dynein activity. However, the mechanism for anchoring PKA in the axoneme is unknown. Here we test the hypothesis that the axoneme contains an A-kinase anchoring protein (AKAP). By performing RII blot overlays on motility mutants defective for specific axonemal structures, two axonemal AKAPs have been identified: a 240-kD AKAP associated with the central pair apparatus, and a 97-kD AKAP located in the radial spoke stalk. Based on a detailed analysis, we have shown that AKAP97 is radial spoke protein 3 (RSP3). By expressing truncated forms of RSP3, we have localized the RII-binding domain to a region between amino acids 144-180. Amino acids 161-180 are homologous with the RII-binding domains of other AKAPs and are predicted to form an amphipathic helix. Amino acid substitution of the central residues of this region (L to P or VL to AA) results in the complete loss of RII binding. RSP3 is located near the inner arm dyneins, where an anchored PKA would be in direct position to modify dynein activity and regulate flagellar motility.
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Affiliation(s)
- Anne Roush Gaillard
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Dennis R. Diener
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut 06520
| | - Joel L. Rosenbaum
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut 06520
| | - Winfield S. Sale
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322
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30
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Abel ES, Davids BJ, Robles LD, Loflin CE, Gillin FD, Chakrabarti R. Possible roles of protein kinase A in cell motility and excystation of the early diverging eukaryote Giardia lamblia. J Biol Chem 2001; 276:10320-9. [PMID: 11104758 DOI: 10.1074/jbc.m006589200] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Since little is known of how the primitive protozoan parasite, Giardia lamblia, senses and responds to its changing environment, we characterized a giardial protein kinase A (gPKA) catalytic subunit with unusual subcellular localization. Sequence analysis of the 1080-base pair open reading frame shows 48% amino acid identity with the cyclic AMP-dependent kinase from Euglena gracilis. Northern analysis indicated a 1.28- kilobase pair transcript at relatively constant concentrations during growth and encystation. gPKA is autophosphorylated, although amino acid residues corresponding to Thr-197 and Ser-338 of human protein kinase A (PKA) that are important for autophosphorylation are absent. Kinetic analysis of the recombinant PKA showed that ATP and magnesium are preferred over GTP and manganese. Kinase activity of the native PKA has also been detected in crude extracts using kemptide as a substrate. A myristoylated PKA inhibitor, amide 14-22, inhibited excystation with an IC(50) of 3 microm, suggesting an important role of gPKA during differentiation from the dormant cyst form into the active trophozoite. gPKA localizes independently of cell density to the eight flagellar basal bodies between the two nuclei together with centrin, a basal body/centrosome-specific protein. However, localization of gPKA to marginal plates along the intracellular portions of the anterior and caudal pairs of flagella was evident only at low cell density and higher endogenous cAMP concentrations or after refeeding with fresh medium. These data suggest an important role of PKA in trophozoite motility during vegetative growth and the cellular activation of excystation.
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Affiliation(s)
- E S Abel
- Department of Molecular Biology and Microbiology, University of Central Florida, Orlando, Florida 32826, USA
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31
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Turner RM, Eriksson RL, Gerton GL, Moss SB. Relationship between sperm motility and the processing and tyrosine phosphorylation of two human sperm fibrous sheath proteins, pro-hAKAP82 and hAKAP82. Mol Hum Reprod 1999; 5:816-24. [PMID: 10460219 DOI: 10.1093/molehr/5.9.816] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sperm motility is regulated by the cAMP-dependent protein kinase (protein kinase-A)-mediated phosphorylation of a group of largely unidentified flagellar proteins. Human AKAP82 (hAKAP82) and its precursor protein, pro-hAKAP82, are members of the A-kinase anchor protein (AKAP) family. These proteins tether protein kinase-A to the fibrous sheath of human spermatozoa and presumably localize the activity of the kinase near specific targets in the sperm flagellum. In this way, pro-hAKAP82 and hAKAP82 may be involved in regulating sperm motility. Similar to its homologues in other species, pro-hAKAP82 is proteolytically processed to hAKAP82. However, the amount of processing of pro-hAKAP82 in human spermatozoa is less than the amount of processing of the precursor in other species. We postulated that this lower extent of processing may be related to lower percentages of human sperm motility. In addition, both pro-hAKAP82 and hAKAP82 are tyrosine phosphorylated in a capacitation-dependent manner. Since capacitation is associated with hyperactivated motility, we postulated that tyrosine phosphorylation of pro-hAKAP82/hAKAP82 is associated with changes in motility. However, using a combination of immunofluorescence and immunoblotting approaches, we found no evidence for an association between either processing or tyrosine phosphorylation of pro-hAKAP82/hAKAP82 and significant differences in motility in spermatozoa from normal men.
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Affiliation(s)
- R M Turner
- Center for Research on Reproduction and Women's Health, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, 421 Curie Blvd., Philadelphia, PA 19104, USA
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