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Ferrero G, Festa R, Follia L, Lettieri G, Tarallo S, Notari T, Giarra A, Marinaro C, Pardini B, Marano A, Piaggeschi G, Di Battista C, Trifuoggi M, Piscopo M, Montano L, Naccarati A. Small noncoding RNAs and sperm nuclear basic proteins reflect the environmental impact on germ cells. Mol Med 2024; 30:12. [PMID: 38243211 PMCID: PMC10799426 DOI: 10.1186/s10020-023-00776-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 12/26/2023] [Indexed: 01/21/2024] Open
Abstract
BACKGROUND Molecular techniques can complement conventional spermiogram analyses to provide new information on the fertilizing potential of spermatozoa and to identify early alterations due to environmental pollution. METHODS Here, we present a multilevel molecular profiling by small RNA sequencing and sperm nuclear basic protein analysis of male germ cells from 33 healthy young subjects residing in low and high-polluted areas. RESULTS Although sperm motility and sperm concentration were comparable between samples from the two sites, those from the high-pollution area had a higher concentration of immature/immune cells, a lower protamine/histone ratio, a reduced ability of sperm nuclear basic proteins to protect DNA from oxidative damage, and an altered copper/zinc ratio in sperm. Sperm levels of 32 microRNAs involved in intraflagellar transport, oxidative stress response, and spermatogenesis were different between the two areas. In parallel, a decrease of Piwi-interacting RNA levels was observed in samples from the high-polluted area. CONCLUSIONS This comprehensive analysis provides new insights into pollution-driven epigenetic alterations in sperm not detectable by spermiogram.
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Affiliation(s)
- Giulio Ferrero
- Department of Clinical and Biological Sciences, University of Turin, Regione Gonzole 10, 10043, Orbassano, Turin, Italy
- Department of Computer Science, University of Turin, Corso Svizzera, 185, 10149, Turin, Italy
| | - Rosaria Festa
- Department of Biology, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy
| | - Laura Follia
- Department of Clinical and Biological Sciences, University of Turin, Regione Gonzole 10, 10043, Orbassano, Turin, Italy
| | - Gennaro Lettieri
- Department of Biology, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy
| | - Sonia Tarallo
- Italian Institute for Genomic Medicine (IIGM), c/o IRCCS Candiolo, SP 142 Km. 3,95, 10060, Candiolo, Turin, Italy
| | - Tiziana Notari
- Check-Up PolyDiagnostic and Research Laboratory, Andrology Unit, Viale Andrea De Luca 5, 84131, Salerno, Italy
| | - Antonella Giarra
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy
| | - Carmela Marinaro
- Department of Biology, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy
| | - Barbara Pardini
- Italian Institute for Genomic Medicine (IIGM), c/o IRCCS Candiolo, SP 142 Km. 3,95, 10060, Candiolo, Turin, Italy
| | - Alessandra Marano
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy
| | - Giulia Piaggeschi
- Italian Institute for Genomic Medicine (IIGM), c/o IRCCS Candiolo, SP 142 Km. 3,95, 10060, Candiolo, Turin, Italy
| | - Carla Di Battista
- Italian Institute for Genomic Medicine (IIGM), c/o IRCCS Candiolo, SP 142 Km. 3,95, 10060, Candiolo, Turin, Italy
| | - Marco Trifuoggi
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy
| | - Marina Piscopo
- Department of Biology, University of Naples Federico II, Via Cinthia, 21, 80126, Naples, Italy.
| | - Luigi Montano
- Andrology Unit and Service of Lifestyle Medicine in UroAndrology, Local Health Authority (ASL) Salerno, Coordination Unit of the Network for Environmental and Reproductive Health (Eco-FoodFertility Project), S. Francesco di Assisi Hospital, 84020, Oliveto Citra, Salerno, Italy.
- PhD Program in Evolutionary Biology and Ecology, University of Rome Tor Vergata, 00133, Rome, Italy.
| | - Alessio Naccarati
- Italian Institute for Genomic Medicine (IIGM), c/o IRCCS Candiolo, SP 142 Km. 3,95, 10060, Candiolo, Turin, Italy
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2
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Merges GE, Arévalo L, Kovacevic A, Lohanadan K, de Rooij DG, Simon C, Jokwitz M, Witke W, Schorle H. Actl7b deficiency leads to mislocalization of LC8 type dynein light chains and disruption of murine spermatogenesis. Development 2023; 150:dev201593. [PMID: 37800308 PMCID: PMC10652042 DOI: 10.1242/dev.201593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 09/22/2023] [Indexed: 10/07/2023]
Abstract
Actin-related proteins (Arps) are classified according to their similarity to actin and are involved in diverse cellular processes. ACTL7B is a testis-specific Arp, and is highly conserved in rodents and primates. ACTL7B is specifically expressed in round and elongating spermatids during spermiogenesis. Here, we have generated an Actl7b-null allele in mice to unravel the role of ACTL7B in sperm formation. Male mice homozygous for the Actl7b-null allele (Actl7b-/-) were infertile, whereas heterozygous males (Actl7b+/-) were fertile. Severe spermatid defects, such as detached acrosomes, disrupted membranes and flagella malformations start to appear after spermiogenesis step 9 in Actl7b-/- mice, finally resulting in spermatogenic arrest. Abnormal spermatids were degraded and levels of autophagy markers were increased. Co-immunoprecipitation with mass spectrometry experiments identified an interaction between ACTL7B and the LC8 dynein light chains DYNLL1 and DYNLL2, which are first detected in step 9 spermatids and mislocalized when ACTL7B is absent. Our data unequivocally establish that mutations in ACTL7B are directly related to male infertility, pressing for additional research in humans.
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Affiliation(s)
- Gina E. Merges
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Lena Arévalo
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Andjela Kovacevic
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Keerthika Lohanadan
- Department of Molecular Cell Biology, Institute for Cell Biology, University of Bonn, 53121 Bonn, Germany
| | - Dirk G. de Rooij
- Reproductive Biology Group, Division of Developmental Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Carla Simon
- Cell Migration Unit, Institute of Genetics, University of Bonn, 53115 Bonn, Germany
| | - Melanie Jokwitz
- Cell Migration Unit, Institute of Genetics, University of Bonn, 53115 Bonn, Germany
| | - Walter Witke
- Cell Migration Unit, Institute of Genetics, University of Bonn, 53115 Bonn, Germany
| | - Hubert Schorle
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
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3
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Chang CH, Mejia Natividad I, Malik HS. Expansion and loss of sperm nuclear basic protein genes in Drosophila correspond with genetic conflicts between sex chromosomes. eLife 2023; 12:85249. [PMID: 36763410 PMCID: PMC9917458 DOI: 10.7554/elife.85249] [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: 11/30/2022] [Accepted: 01/04/2023] [Indexed: 02/11/2023] Open
Abstract
Many animal species employ sperm nuclear basic proteins (SNBPs) or protamines to package sperm genomes tightly. SNBPs vary across animal lineages and evolve rapidly in mammals. We used a phylogenomic approach to investigate SNBP diversification in Drosophila species. We found that most SNBP genes in Drosophila melanogaster evolve under positive selection except for genes essential for male fertility. Unexpectedly, evolutionarily young SNBP genes are more likely to be critical for fertility than ancient, conserved SNBP genes. For example, CG30056 is dispensable for male fertility despite being one of three SNBP genes universally retained in Drosophila species. We found 19 independent SNBP gene amplification events that occurred preferentially on sex chromosomes. Conversely, the montium group of Drosophila species lost otherwise-conserved SNBP genes, coincident with an X-Y chromosomal fusion. Furthermore, SNBP genes that became linked to sex chromosomes via chromosomal fusions were more likely to degenerate or relocate back to autosomes. We hypothesize that autosomal SNBP genes suppress meiotic drive, whereas sex-chromosomal SNBP expansions lead to meiotic drive. X-Y fusions in the montium group render autosomal SNBPs dispensable by making X-versus-Y meiotic drive obsolete or costly. Thus, genetic conflicts between sex chromosomes may drive SNBP rapid evolution during spermatogenesis in Drosophila species.
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Affiliation(s)
- Ching-Ho Chang
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, United States
| | - Isabel Mejia Natividad
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Center, Seattle, United States
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Center, Seattle, United States
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4
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Merges GE, Meier J, Schneider S, Kruse A, Fröbius AC, Kirfel G, Steger K, Arévalo L, Schorle H. Loss of Prm1 leads to defective chromatin protamination, impaired PRM2 processing, reduced sperm motility and subfertility in male mice. Development 2022; 149:275502. [PMID: 35608054 PMCID: PMC9270976 DOI: 10.1242/dev.200330] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 05/12/2022] [Indexed: 12/12/2022]
Abstract
One of the key events during spermiogenesis is the hypercondensation of chromatin by substitution of the majority of histones by protamines. In humans and mice, protamine 1 (PRM1/Prm1) and protamine 2 (PRM2/Prm2) are expressed in a species-specific ratio. Using CRISPR-Cas9-mediated gene editing, we generated Prm1-deficient mice and demonstrated that Prm1+/- mice were subfertile, whereas Prm1-/- mice were infertile. Prm1-/- and Prm2-/- sperm showed high levels of reactive oxygen species-mediated DNA damage and increased histone retention. In contrast, Prm1+/- sperm displayed only moderate DNA damage. The majority of Prm1+/- sperm were CMA3 positive, indicating protamine-deficient chromatin, although this was not the result of increased histone retention in Prm1+/- sperm. However, sperm from Prm1+/- and Prm1-/- mice contained high levels of incompletely processed PRM2. Furthermore, the PRM1:PRM2 ratio was skewed from 1:2 in wild type to 1:5 in Prm1+/- animals. Our results reveal that PRM1 is required for proper PRM2 processing to produce mature PRM2, which, together with PRM1, is able to hypercondense DNA. Thus, the species-specific PRM1:PRM2 ratio has to be precisely controlled in order to retain full fertility.
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Affiliation(s)
- Gina Esther Merges
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Julia Meier
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Simon Schneider
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Alexander Kruse
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Biomedical Research Center of the Justus-Liebig University, 35392 Giessen, Germany
| | - Andreas Christian Fröbius
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Biomedical Research Center of the Justus-Liebig University, 35392 Giessen, Germany
| | - Gregor Kirfel
- Department of Molecular Cell Biology, Institute for Cell Biology, University of Bonn, 53121 Bonn, Germany
| | - Klaus Steger
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Biomedical Research Center of the Justus-Liebig University, 35392 Giessen, Germany
| | - Lena Arévalo
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Hubert Schorle
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
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5
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Arévalo L, Merges GE, Schneider S, Oben FE, Neumann IS, Schorle H. Loss of the cleaved-protamine 2 domain leads to incomplete histone-to-protamine exchange and infertility in mice. PLoS Genet 2022; 18:e1010272. [PMID: 35763544 PMCID: PMC9273070 DOI: 10.1371/journal.pgen.1010272] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 07/11/2022] [Accepted: 05/24/2022] [Indexed: 12/13/2022] Open
Abstract
Protamines are unique sperm-specific proteins that package and protect paternal chromatin until fertilization. A subset of mammalian species expresses two protamines (PRM1 and PRM2), while in others PRM1 is sufficient for sperm chromatin packaging. Alterations of the species-specific ratio between PRM1 and PRM2 are associated with infertility. Unlike PRM1, PRM2 is generated as a precursor protein consisting of a highly conserved N-terminal domain, termed cleaved PRM2 (cP2), which is consecutively trimmed off during chromatin condensation. The carboxyterminal part, called mature PRM2 (mP2), interacts with DNA and together with PRM1, mediates chromatin-hypercondensation. The removal of the cP2 domain is believed to be imperative for proper chromatin condensation, yet, the role of cP2 is not yet understood. We generated mice lacking the cP2 domain while the mP2 is still expressed. We show that the cP2 domain is indispensable for complete sperm chromatin protamination and male mouse fertility. cP2 deficient sperm show incomplete protamine incorporation and a severely altered protamine ratio, retention of transition proteins and aberrant retention of the testis specific histone variant H2A.L.2. During epididymal transit, cP2 deficient sperm seem to undergo ROS mediated degradation leading to complete DNA fragmentation. The cP2 domain therefore seems to be a key aspect in the complex crosstalk between histones, transition proteins and protamines during sperm chromatin condensation. Overall, we present the first step towards understanding the role of the cP2 domain in paternal chromatin packaging and open up avenues for further research. Protamines are small sperm-specific proteins crucial to packaging and protecting the paternal genome on its way to the fertilization site. Most mammalian species express only protamine 1. However, primates and rodents additionally express protamine 2. Protamine 2 differs mainly in its N-terminal domain (cP2), which is sequentially cleaved off during paternal chromatin packaging. Alteration in this process has been associated with infertility. However, the precise role of cP2 is still a mystery. We generated cP2 deficient mice and demonstrate, that loss of cP2 results in incomplete histone-to-protamine transition, resulting in sperm DNA degradation and infertility. Evidently, cP2 helps in orchestrating the fine-tuned dynamics of DNA-hypercondensation while protecting DNA integrity and aiding removal of DNA-bound transition proteins.
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Affiliation(s)
- Lena Arévalo
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
- * E-mail: (LA); (HS)
| | - Gina Esther Merges
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Simon Schneider
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Franka Enow Oben
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Isabelle Sophie Neumann
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Hubert Schorle
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
- * E-mail: (LA); (HS)
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6
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Rezaei-Gazik M, Vargas A, Amiri-Yekta A, Vitte AL, Akbari A, Barral S, Esmaeili V, Chuffart F, Sadighi-Gilani MA, Couté Y, Eftekhari-Yazdi P, Khochbin S, Rousseaux S, Totonchi M. Direct visualization of pre-protamine 2 detects protamine assembly failures and predicts ICSI success. Mol Hum Reprod 2022; 28:6527641. [PMID: 35150275 DOI: 10.1093/molehr/gaac004] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
Histone-to-protamine transition is an essential step in the generation of fully functional spermatozoa in various mammalian species. In human and mouse, one of the two protamine-encoding genes produces a precursor pre-protamine 2 (pre-PRM2) protein, which is then processed and assembled. Here we design an original approach based on the generation of pre-PRM2-specific antibodies to visualize the unprocessed pre-PRM2 by microscopy, flow cytometry and immunoblotting. Using mouse models with characterized failures in histone-to-protamine replacement, we show that pre-Prm2 retention is tightly linked to nucleosome disassembly. Additionally, in elongating/condensing spermatids, we observe that pre-Prm2 and transition protein are co-expressed spatiotemporally, and their physical interaction suggests that these proteins act simultaneously rather than successively during histone replacement. By using our anti-human pre-PRM2 antibody we also measured pre-PRM2 retention rates in the spermatozoa from 49 men of a series of infertile couples undergoing ICSI, which shed new light on the debated relation between pre-PRM2 retention and sperm parameters. Finally, by monitoring 2-pronuclei (2PN) embryo formation following ICSI, we evaluated the fertilization ability of the sperm in these 49 patients. Our results suggest that the extent of pre-PRM2 retention in sperm, rather than pre-PRM2 accumulation per se, is associated with fertilization failure. Hence, anti-pre-PRM2/pre-Prm2 antibodies are valuable tools which could be used in routine monitoring of sperm parameters in fertility clinics, as well as in experimental research programmes to better understand the obscure process of histone-to-protamine transition.
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Affiliation(s)
- Maryam Rezaei-Gazik
- Department of Developmental Biology, University of Science and Culture, Tehran, Iran.,Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Alexandra Vargas
- CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Amir Amiri-Yekta
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.,CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Anne-Laure Vitte
- CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Arvand Akbari
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Sophie Barral
- CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Vahid Esmaeili
- Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Florent Chuffart
- CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Mohammad Ali Sadighi-Gilani
- Department of Andrology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Yohann Couté
- Université Grenoble Alpes; Inserm, CEA, UMR BioSanté U1292, CNRS CEA FR2048, Grenoble, 38000, France
| | - Poopak Eftekhari-Yazdi
- Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Saadi Khochbin
- CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Sophie Rousseaux
- CNRS UMR 5309, Inserm U1209, Université Grenoble Alpes, Institute for Advanced Biosciences, Grenoble, 38700, France
| | - Mehdi Totonchi
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
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7
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Teves ME, Roldan ERS. Sperm bauplan and function and underlying processes of sperm formation and selection. Physiol Rev 2022; 102:7-60. [PMID: 33880962 PMCID: PMC8812575 DOI: 10.1152/physrev.00009.2020] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 04/14/2021] [Accepted: 04/19/2021] [Indexed: 01/03/2023] Open
Abstract
The spermatozoon is a highly differentiated and polarized cell, with two main structures: the head, containing a haploid nucleus and the acrosomal exocytotic granule, and the flagellum, which generates energy and propels the cell; both structures are connected by the neck. The sperm's main aim is to participate in fertilization, thus activating development. Despite this common bauplan and function, there is an enormous diversity in structure and performance of sperm cells. For example, mammalian spermatozoa may exhibit several head patterns and overall sperm lengths ranging from ∼30 to 350 µm. Mechanisms of transport in the female tract, preparation for fertilization, and recognition of and interaction with the oocyte also show considerable variation. There has been much interest in understanding the origin of this diversity, both in evolutionary terms and in relation to mechanisms underlying sperm differentiation in the testis. Here, relationships between sperm bauplan and function are examined at two levels: first, by analyzing the selective forces that drive changes in sperm structure and physiology to understand the adaptive values of this variation and impact on male reproductive success and second, by examining cellular and molecular mechanisms of sperm formation in the testis that may explain how differentiation can give rise to such a wide array of sperm forms and functions.
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Affiliation(s)
- Maria Eugenia Teves
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, Virginia
| | - Eduardo R S Roldan
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain
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8
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Arévalo L, Tourmente M, Varea-Sánchez M, Ortiz-García D, Roldan ERS. Sexual selection towards a protamine expression ratio optimum in two rodent groups? Evolution 2021; 75:2124-2131. [PMID: 34224143 DOI: 10.1111/evo.14305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 06/18/2021] [Accepted: 06/25/2021] [Indexed: 02/06/2023]
Abstract
Post-copulatory sexual selection is thought to influence the evolution of genes involved in reproduction. However, the detection of straightforward effects has been proven difficult due to the complexity and diversity of reproductive landscapes found in different taxa. Here, we compare the possible effect of relative testes mass as a sperm competition proxy on protamine genotype (protamine 1/protamine 2 ratio) and the link to sperm head phenotype in two rodent groups, mice, and voles. In mice, protamine expression ratios were found to increase from low values toward a 1:1 ratio in a positive association with testes mass, and relative sperm head area. In contrast, in voles, decreasing protamine expression ratios were found in species with larger testes but, surprisingly, they range from high values, again toward a 1:1 ratio, and showing a negative correlation with relative sperm head area. Altogether, we found differences in the way protamines seem to be selected and involved in adaptations of the sperm head in voles and mice. However, sexual selection driven by sperm competition seems to exhibit a common evolutionary pattern in both groups toward an equilibrium in the expression of the two protamines.
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Affiliation(s)
- Lena Arévalo
- Reproductive Ecology and Biology Group, Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, 28006, Spain.,Developmental Pathology, University of Bonn Medical School, Bonn, 53127, Germany
| | - Maximiliano Tourmente
- Reproductive Ecology and Biology Group, Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, 28006, Spain.,Centre for Cell and Molecular Biology. Faculty of Exact, Physical and Natural Sciences, Universidad Nacional de Córdoba, Córdoba, X5016GCA, Argentina.,Institute for Biological and Technological Research (IIByT), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, X5016GCA, Argentina
| | - María Varea-Sánchez
- Reproductive Ecology and Biology Group, Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, 28006, Spain
| | - Daniel Ortiz-García
- Reproductive Ecology and Biology Group, Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, 28006, Spain
| | - Eduardo R S Roldan
- Reproductive Ecology and Biology Group, Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, 28006, Spain
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9
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Słowińska M, Paukszto Ł, Paweł Jastrzębski J, Bukowska J, Kozłowski K, Jankowski J, Ciereszko A. Transcriptome analysis of turkey (Meleagris gallopavo) reproductive tract revealed key pathways regulating spermatogenesis and post-testicular sperm maturation. Poult Sci 2020; 99:6094-6118. [PMID: 33142529 PMCID: PMC7647744 DOI: 10.1016/j.psj.2020.07.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/11/2020] [Accepted: 07/14/2020] [Indexed: 01/11/2023] Open
Abstract
The application of transcriptomics to the study of the reproductive tract in male turkeys can significantly increase our current knowledge regarding the specifics of bird reproduction. To characterize the complex transcriptomic changes that occur in the testis, epididymis, and ductus deferens, deep sequencing of male turkey RNA samples (n = 6) was performed, using Illumina RNA-Seq. The obtained sequence reads were mapped to the turkey genome, and relative expression values were calculated to analyze differentially expressed genes (DEGs). Statistical analysis revealed 1,682; 2,150; and 340 DEGs in testis/epididymis, testis/ductus deferens, and epididymis/ductus deferens comparisons, respectively. The expression of selected genes was validated using quantitative real-time reverse transcriptase-polymerase chain reaction. Bioinformatics analysis revealed several potential candidate genes involved in spermatogenesis, spermiogenesis and flagellum formation in the testis, and in post-testicular sperm maturation in the epididymis and ductus deferens. In the testis, genes were linked with the mitotic proliferation of spermatogonia and the meiotic division of spermatocytes. Histone ubiquitination and protamine phosphorylation were shown to be regulatory mechanisms for nuclear condensation during spermiogenesis. The characterization of testicular transcripts allowed a better understanding of acrosome formation and development and flagellum formation, including axoneme structures and functions. Spermatozoa motility during post-testicular maturation was linked to the development of flagellar actin filaments and biochemical processes, including Ca2+ influx and protein phosphorylation/dephosphorylation. Spermatozoa quality appeared to be controlled by apoptosis and antioxidant systems in the epididymis and ductus deferens. Finally, genes associated with reproductive system development and morphogenesis were identified. To the best of our knowledge, this is the first genome-wide functional investigation of genes associated with tissue-specific processes in turkey reproductive tract. A catalog of genes worthy of further studies to understand the avian reproductive physiology and regulation was provided.
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Affiliation(s)
- Mariola Słowińska
- Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland.
| | - Łukasz Paukszto
- Department of Plant Physiology, Genetics, and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Jan Paweł Jastrzębski
- Department of Plant Physiology, Genetics, and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Joanna Bukowska
- In Vitro and Cell Biotechnology Laboratory, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland
| | - Krzysztof Kozłowski
- Department of Poultry Science, Faculty of Animal Bioengineering, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Jan Jankowski
- Department of Poultry Science, Faculty of Animal Bioengineering, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Andrzej Ciereszko
- Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, 10-748 Olsztyn, Poland
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10
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Arévalo L, Brukman NG, Cuasnicú PS, Roldan ERS. Evolutionary analysis of genes coding for Cysteine-RIch Secretory Proteins (CRISPs) in mammals. BMC Evol Biol 2020; 20:67. [PMID: 32513118 PMCID: PMC7278046 DOI: 10.1186/s12862-020-01632-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Accepted: 05/25/2020] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Cysteine-RIch Secretory Proteins (CRISP) are expressed in the reproductive tract of mammalian males and are involved in fertilization and related processes. Due to their important role in sperm performance and sperm-egg interaction, these genes are likely to be exposed to strong selective pressures, including postcopulatory sexual selection and/or male-female coevolution. We here perform a comparative evolutionary analysis of Crisp genes in mammals. Currently, the nomenclature of CRISP genes is confusing, as a consequence of discrepancies between assignments of orthologs, particularly due to numbering of CRISP genes. This may generate problems when performing comparative evolutionary analyses of mammalian clades and species. To avoid such problems, we first carried out a study of possible orthologous relationships and putative origins of the known CRISP gene sequences. Furthermore, and with the aim to facilitate analyses, we here propose a different nomenclature for CRISP genes (EVAC1-4, "EVolutionarily-analyzed CRISP") to be used in an evolutionary context. RESULTS We found differing selective pressures among Crisp genes. CRISP1/4 (EVAC1) and CRISP2 (EVAC2) orthologs are found across eutherian mammals and seem to be conserved in general, but show signs of positive selection in primate CRISP1/4 (EVAC1). Rodent Crisp1 (Evac3a) seems to evolve under a comparatively more relaxed constraint with positive selection on codon sites. Finally, murine Crisp3 (Evac4), which appears to be specific to the genus Mus, shows signs of possible positive selection. We further provide evidence for sexual selection on the sequence of one of these genes (Crisp1/4) that, unlike others, is thought to be exclusively expressed in male reproductive tissues. CONCLUSIONS We found differing selective pressures among CRISP genes and sexual selection as a contributing factor in CRISP1/4 gene sequence evolution. Our evolutionary analysis of this unique set of genes contributes to a better understanding of Crisp function in particular and the influence of sexual selection on reproductive mechanisms in general.
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Affiliation(s)
- Lena Arévalo
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), c/José Gutiérrez Abascal 2, 28006 Madrid, Spain
- Institute of Pathology, Department of Developmental Pathology, University Hospital Bonn, Bonn, 53127 Germany
| | - Nicolás G. Brukman
- Instituto de Biología y Medicina Experimental (IBYME-CONICET), C1428ADN Buenos Aires, Argentina
| | - Patricia S. Cuasnicú
- Instituto de Biología y Medicina Experimental (IBYME-CONICET), C1428ADN Buenos Aires, Argentina
| | - Eduardo R. S. Roldan
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), c/José Gutiérrez Abascal 2, 28006 Madrid, Spain
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11
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Powell CD, Kirchoff DC, DeRouchey JE, Moseley HNB. Entropy based analysis of vertebrate sperm protamines sequences: evidence of potential dityrosine and cysteine-tyrosine cross-linking in sperm protamines. BMC Genomics 2020; 21:277. [PMID: 32245406 PMCID: PMC7126135 DOI: 10.1186/s12864-020-6681-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 03/17/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Spermatogenesis is the process by which germ cells develop into spermatozoa in the testis. Sperm protamines are small, arginine-rich nuclear proteins which replace somatic histones during spermatogenesis, allowing a hypercondensed DNA state that leads to a smaller nucleus and facilitating sperm head formation. In eutherian mammals, the protamine-DNA complex is achieved through a combination of intra- and intermolecular cysteine cross-linking and possibly histidine-cysteine zinc ion binding. Most metatherian sperm protamines lack cysteine but perform the same function. This lack of dicysteine cross-linking has made the mechanism behind metatherian protamines folding unclear. RESULTS Protamine sequences from UniProt's databases were pulled down and sorted into homologous groups. Multiple sequence alignments were then generated and a gap weighted relative entropy score calculated for each position. For the eutherian alignments, the cysteine containing positions were the most highly conserved. For the metatherian alignment, the tyrosine containing positions were the most highly conserved and corresponded to the cysteine positions in the eutherian alignment. CONCLUSIONS High conservation indicates likely functionally/structurally important residues at these positions in the metatherian protamines and the correspondence with cysteine positions within the eutherian alignment implies a similarity in function. One possible explanation is that the metatherian protamine structure relies upon dityrosine cross-linking between these highly conserved tyrosines. Also, the human protamine P1 sequence has a tyrosine substitution in a position expecting eutherian dicysteine cross-linking. Similarly, some members of the metatherian Planigales genus contain cysteine substitutions in positions expecting plausible metatherian dityrosine cross-linking. Rare cysteine-tyrosine cross-linking could explain both observations.
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Affiliation(s)
- Christian D. Powell
- Department of Chemistry, University of Kentucky, 161 Jacobs Science Building, Lexington, 40506 USA
- Markey Cancer Center, University of Kentucky, 800 Rose Street, Pavilion CC, Lexington, 40536 USA
| | - Daniel C. Kirchoff
- Department of Chemistry, University of Kentucky, 161 Jacobs Science Building, Lexington, 40506 USA
| | - Jason E. DeRouchey
- Department of Chemistry, University of Kentucky, 161 Jacobs Science Building, Lexington, 40506 USA
| | - Hunter N. B. Moseley
- Markey Cancer Center, University of Kentucky, 800 Rose Street, Pavilion CC, Lexington, 40536 USA
- Department of Molecular & Cellular Biochemistry, University of Kentucky, Lexington, 40508 USA
- Institute for Biomedical Informatics, University of Kentucky, Lexington, 40536 USA
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12
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Schaschl H, Wallner B. Population-specific, recent positive directional selection suggests adaptation of human male reproductive genes to different environmental conditions. BMC Evol Biol 2020; 20:27. [PMID: 32054438 PMCID: PMC7020506 DOI: 10.1186/s12862-019-1575-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 12/30/2019] [Indexed: 01/18/2023] Open
Abstract
Background Recent human transcriptomic analyses revealed a very large number of testis-enriched genes, many of which are involved in spermatogenesis. This comprehensive transcriptomic data lead us to the question whether positive selection was a decisive force influencing the evolution and variability of testis-enriched genes in humans. We used two methodological approaches to detect different levels of positive selection, namely episodic positive diversifying selection (i.e., past selection) in the human lineage within primate phylogeny, potentially driven by sperm competition, and recent positive directional selection in contemporary human populations, which would indicate adaptation to different environments. Results In the human lineage (after correction for multiple testing) we found that only the gene TULP2, for which no functional data are yet available, is subject to episodic positive diversifying selection. Using less stringent statistical criteria (uncorrected p-values), also the gene SPATA16, which has a pivotal role in male fertility and for which episodes of adaptive evolution have been suggested, also displays a putative signal of diversifying selection in the human branch. At the same time, we found evidence for recent positive directional selection acting on several human testis-enriched genes (MORC1, SLC9B1, ROPN1L, DMRT1, PLCZ1, RNF17, FAM71D and WBP2NL) that play important roles in human spermatogenesis and fertilization. Most of these genes are population-specifically under positive selection. Conclusion Episodic diversifying selection, possibly driven by sperm competition, was not an important force driving the evolution of testis-enriched genes in the human lineage. Population-specific, recent positive directional selection suggests an adaptation of male reproductive genes to different environmental conditions. Positive selection acts on eQTLS and sQTLs, indicating selective effects on important gene regulatory functions. In particular, the transcriptional diversity regulated by sQTLs in testis-enriched genes may be important for spermatocytes to respond to environmental and physiological stress.
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Affiliation(s)
- Helmut Schaschl
- Department of Evolutionary Anthropology, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
| | - Bernard Wallner
- Department of Behavioural Biology, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria
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13
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Epigenetic changes in mammalian gametes throughout their lifetime: the four seasons metaphor. Chromosoma 2019; 128:423-441. [DOI: 10.1007/s00412-019-00704-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/03/2019] [Accepted: 04/11/2019] [Indexed: 01/22/2023]
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Hamilton TRS, Simões R, Mendes CM, Goissis MD, Nakajima E, Martins EAL, Visintin JA, Assumpção MEOA. Detection of protamine 2 in bovine spermatozoa and testicles. Andrology 2019; 7:373-381. [PMID: 30920782 DOI: 10.1111/andr.12610] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/14/2019] [Accepted: 02/25/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Sperm DNA integrity is crucial for transmission of genetic information to future generations and DNA damage can occur during chromatin packaging. Chromatin packaging involves the replacement of somatic nucleosomal histones by nuclear proteins called protamines. Protamine 1 (PRM1) is transcribed and translated in spermatids of all mammals; however, protamine 2 (PRM2) is transcribed in low levels in spermatids and it is not yet described in bull mature spermatozoa. OBJECTIVES The aim of this study was to assess gene and protein expression of PRM2 and corroborate gene and protein expression of PRM1 in bull spermatozoa and testis. MATERIALS AND METHODS For this purpose, absolute q-RT-PCR was performed to calculate the number of copies of PRM1 and PRM2 mRNAs in bovine epididymal spermatozoa and testicular tissue. Western blot and mass spectrometry were performed to identify PRM1 and PRM2 in samples of bovine epididymal spermatozoa. Samples of bovine testicular tissue were collected to identify PRM1 and PRM2 by immunohistochemistry. RESULTS We evaluated that the number of PRM1 mRNA copies was about hundred times higher than PRM2 mRNA copies in sperm and testicular samples (p < 0.0001). In addition, we estimated the PRM1: PRM2 ratio based on mRNA number of copies. In spermatozoa, the ratio was 1: 0.014, and in testicle, the ratio was 1: 0.009. We also evaluated the immunolocalization for PRM1 and PRM2 in bovine testis, and both proteins were detected in spermatids. Western blot and mass spectrometry in bovine epididymal spermatozoa confirmed these results. CONCLUSION Our work identifies, for the first time, PRM2 in bovine epididymal spermatozoa and in testis. Further studies are still needed to understand the role of PRM2 on the chromatin of the spermatozoa and to verify how possible changes in PRM2 levels may influence the bull fertility.
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Affiliation(s)
- T R S Hamilton
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - R Simões
- Center for Natural and Human Sciences, Federal University of ABC, Santo André, Brazil
| | - C M Mendes
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - M D Goissis
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - E Nakajima
- Process Development Laboratory, Inovation Division, Butantan Institute, São Paulo, Brazil
| | - E A L Martins
- Process Development Laboratory, Inovation Division, Butantan Institute, São Paulo, Brazil
| | - J A Visintin
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - M E O A Assumpção
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
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Balhorn R, Steger K, Bergmann M, Schuppe HC, Neuhauser S, Balhorn MC. New monoclonal antibodies specific for mammalian protamines P1 and P2. Syst Biol Reprod Med 2018; 64:424-447. [DOI: 10.1080/19396368.2018.1510063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Rod Balhorn
- Briar Patch Biosciences LLC, Livermore, CA, USA
| | - Klaus Steger
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Justus Liebig University, Giessen, Germany
| | - Martin Bergmann
- Department of Veterinary Anatomy, Histology and Embryology, Giessen, Germany
| | | | - Stefanie Neuhauser
- Pferdezentrum Bad Saarow, Veterinary Faculty of the University, Berlin, Germany
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Steger K, Balhorn R. Sperm nuclear protamines: A checkpoint to control sperm chromatin quality. Anat Histol Embryol 2018; 47:273-279. [PMID: 29797354 DOI: 10.1111/ahe.12361] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 04/17/2018] [Indexed: 12/22/2022]
Abstract
Protamines are nuclear proteins which are specifically expressed in haploid male germ cells. Their replacement of histones and binding to DNA is followed by chromatin hypercondensation that protects DNA from negative influences by environmental factors. Mammalian sperm contain two types of protamines: PRM1 and PRM2. While the proportion of the two protamines is highly variable between different species, abnormal ratios within a species are known to be associated with male subfertility. Therefore, it is more than likely that correct protamine expression represents a kind of chromatin checkpoint during sperm development rendering protamines as suitable biomarkers for the estimation of sperm quality. This review presents an overview of our current knowledge on protamines comparing gene and protein structures between different mammalian species with particular consideration given to man, mouse and stallion. At last, recent insights into the possible role of inherited sperm histones for early embryo development are provided.
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Affiliation(s)
- Klaus Steger
- Department of Urology, Pediatric Urology and Andrology, Molecular Andrology, Biomedical Research Center of the Justus Liebig University, Giessen, Germany
| | - Rod Balhorn
- Briar Patch Biosciences LLC, Livermore, CA, USA
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Re-visiting the Protamine-2 locus: deletion, but not haploinsufficiency, renders male mice infertile. Sci Rep 2016; 6:36764. [PMID: 27833122 PMCID: PMC5105070 DOI: 10.1038/srep36764] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/20/2016] [Indexed: 12/26/2022] Open
Abstract
Protamines are arginine-rich DNA-binding proteins that replace histones in elongating spermatids. This leads to hypercondensation of chromatin and ensures physiological sperm morphology, thereby protecting DNA integrity. In mice and humans, two protamines, protamine-1 (Prm1) and protamine-2 (Prm2) are expressed in a species-specific ratio. In humans, alterations of this PRM1/PRM2 ratio is associated with subfertility. By applying CRISPR/Cas9 mediated gene-editing in oocytes, we established Prm2-deficient mice. Surprisingly, heterozygous males remained fertile with sperm displaying normal head morphology and motility. In Prm2-deficient sperm, however, DNA-hypercondensation and acrosome formation was severely impaired. Further, the sperm displayed severe membrane defects resulting in immotility. Thus, lack of Prm2 leads not only to impaired histone to protamine exchange and disturbed DNA-hypercondensation, but also to severe membrane defects resulting in immotility. Interestingly, previous attempts using a regular gene-targeting approach failed to establish Prm2-deficient mice. This was due to the fact that already chimeric animals generated with Prm2+/− ES cells were sterile. However, the Prm2-deficient mouse lines established here clearly demonstrate that mice tolerate loss of one Prm2 allele. As such they present an ideal model for further studies on protamine function and chromatin organization in murine sperm.
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