Comparative Study on the Sperm Proteomes of Horses and Donkeys.
Abstract: The reproductive performance of horse sperm and donkey sperm has been reported to differ. Sperm proteins play a crucial role in sperm viability and fertility. Although differences between species are known, no prior study has investigated disparities in the sperm proteome between horses and donkeys. Therefore, this study characterized and compared the sperm proteomes of horses and donkeys using 4D-DIA mass spectrometry technology. We identified 3436 proteins in horse sperm and 3404 proteins in donkey sperm. Of these, 3363 proteins were expressed in both horse and donkey sperm, with 73 proteins being specifically expressed in horse sperm, and 41 in donkey sperm. According to data analysis, donkeys exhibited a greater percentage of motility and progressive movement in straight-line sperm than horses, as well as lower percentages of static and slow sperm than horses. Joint analysis of the results from the horse and donkey sperm proteomes and their CEROS II-read parameters demonstrated a possible association between sperm proteins and their sperm viability patterns. These findings suggest that there are discrepancies in the expression levels and protein compositions of horse and donkey sperm and that certain specific proteins may be responsible for the differences in performance between these two species.
Publication Date: 2024-07-31 PubMed ID: 39123763PubMed Central: PMC11311092DOI: 10.3390/ani14152237Google Scholar: Lookup
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Summary
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This study compared the protein profiles, or proteomes, of horse and donkey sperm to understand the differences in their reproductive performance. They found specific proteins that are only present in each species, which may contribute to differing sperm viability patterns and mobility.
Objective and Methodology of the Study
- The study aimed to examine the differences in the sperm proteomes, the entire set of proteins expressed by an organism, of horses and donkeys. This was instigated by an understanding that the reproductive performance differs between the two species.
- Using 4D-DIA mass spectrometry technology, an advanced technique to identify and quantify proteins, the sperm proteomes of horses and donkeys were characterized and compared.
Findings from the Comparative Analysis
- The study identified a total of 3436 proteins in horse sperm and 3404 proteins in donkey sperm.
- Out of these, 3363 proteins were found to be common in both horse and donkey sperm. Additionally, 73 proteins were exclusively expressed in horse sperm, and 41 in donkey sperm.
- According to their analysis, donkeys showed a higher percentage of mobile and progressively moving sperm compared to horses. On the other hand, horses had a higher percentage of non-moving and slow-moving sperm.
Interpretation and Implications of the Findings
- Data from the horse and donkey sperm proteomes, along with parameters from CEROS II-read, a computer-assisted sperm analysis system, suggest a potential relationship between specific sperm proteins and patterns in sperm viability.
- The differences in protein expression levels and compositions between horse and donkey sperm may be responsible for the varying reproductive performance between the two species.
- The findings also hint towards the role of certain specific proteins as key drivers for the observed discrepancies, though further research is needed to confirm this assumption.
This important study paves the way for a more comprehensive understanding of reproductive performance across different species, which could eventually aid in the improvement of breeding strategies in the future.
Cite This Article
APA
Ren H, Wen X, He Q, Yi M, Dugarjaviin M, Bou G.
(2024).
Comparative Study on the Sperm Proteomes of Horses and Donkeys.
Animals (Basel), 14(15), 2237.
https://doi.org/10.3390/ani14152237 Publication
Researcher Affiliations
- Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Key Laboratory of Equine Science Research and Technology Innovation, Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Key Laboratory of Equine Science Research and Technology Innovation, Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Key Laboratory of Equine Science Research and Technology Innovation, Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Key Laboratory of Equine Science Research and Technology Innovation, Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Key Laboratory of Equine Science Research and Technology Innovation, Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Agricultural University, Hohhot 010018, China.
- Inner Mongolia Key Laboratory of Equine Science Research and Technology Innovation, Inner Mongolia Agricultural University, Hohhot 010018, China.
Grant Funding
- BR220402 / the Basic scientific research operating expenses project of universities directly under the Inner Mongolia Autonomous Region
- NJZY23117 / the science and technology research projects of universities In inner Mongolia Autonomous Region
- DC2300001263 / the 2022 annual high-level talent research support fund project for local public institutions in Inner Mongolia Autonomous Region
- RK2300003392 / the research initiation grant program at Inner Mongolia Agricultural University
Conflict of Interest Statement
The authors declare no conflicts of interest.
References
This article includes 71 references
- Bhardwaj A, Tandon G, Pal Y, Sharma N.K, Nayan V, Soni S, Iquebal M.A, Jaiswal S, Legha R.A, Talluri T.R. Genome-Wide Single-Nucleotide Polymorphism-Based Genomic Diversity and Runs of Homozygosity for Selection Signatures in Equine Breeds. Genes 2023;14:1623.
- Huang B, Khan M.Z, Chai W, Ullah Q, Wang C. Exploring Genetic Markers: Mitochondrial DNA and Genomic Screening for Biodiversity and Production Traits in Donkeys. Animals 2023;13:2725.
- Massari S, Giannico F, Paolillo N.V, Pala A, Jambrenghi A.C, Antonacci R. Genomic and comparative analysis of the T cell receptor gamma locus in two Equus species. Front. Immunol. 2023;14:1264949.
- Sonali, Bhardwaj A, Unnati, Nayan V, Legha R.A, Bhattacharya T.K, Pal Y, Giri S.K. Identification and characterization of single nucleotide polymorphisms in DMRT3 gene in Indian horse (Equus caballus) and donkey (Equus asinus) populations. Anim. Biotechnol. 2023;34:4910–4920.
- Kim S.M, Yun S.W, Cho G.J. Assessment of genetic diversity using microsatellite markers to compare donkeys (Equus asinus) with horses (Equus caballus). Anim. Biosci. 2021;34:1460–1465.
- Al-Kass Z, Ntallaris T, Morrell J.M, Johannisson A. Deciphering sperm chromatin properties to predict stallion sperm fertility. Anim. Reprod. Sci. 2023;250:107200.
- Varner D.D, Gibb Z, Aitken R.J. Stallion fertility: A focus on the spermatozoon. Equine Vet. J. 2015;47:16–24.
- Colenbrander B, Gadella B.M, Stout T.A. The predictive value of semen analysis in the evaluation of stallion fertility. Reprod. Domest. Anim. 2003;38:305–311.
- Liu X, Wang X, Liu F. Decreased expression of heat shock protein A4L in spermatozoa is positively related to poor human sperm quality. Mol. Reprod. Dev. 2019;86:379–386.
- Hernández-Avilés C, Ramírez-Agámez L, Weintraub S.T, Scoggin C.F, Davis B.W, Raudsepp T, Varner D.D, Love C.C. Proteomic analysis of sperm from fertile stallions and subfertile stallions due to impaired acrosomal exocytosis. Sci. Rep. 2024;14:12446.
- Zhou J, Yang F, Leu N.A, Wang P.J. MNS1 is essential for spermiogenesis and motile ciliary functions in mice. PLoS Genet. 2012;8:e1002516.
- Cao H, Xu H, Zhou Y, Xu W, Lu Q, Jiang L, Rong Y, Zhang Q, Yu C. BBOF1 is required for sperm motility and male fertility by stabilizing the flagellar axoneme in mice. Cell Mol. Life Sci. 2023;80:152.
- Wu Y.Q, Rao M, Hu S.F, Ke D.D, Zhu C.H, Xia W. Effect of transient scrotal hyperthermia on human sperm: An iTRAQ-based proteomic analysis. Reprod. Biol. Endocrinol. (RBE) 2020;18:83.
- Fang X, Huang L.L, Xu J, Ma C.Q, Chen Z.H, Zhang Z, Liao C.H, Zheng S.X, Huang P, Xu W.M. Proteomics and single-cell RNA analysis of Akap4-knockout mice model confirm indispensable role of Akap4 in spermatogenesis. Dev. Biol. 2019;454:118–127.
- Blommaert D, Sergeant N, Delehedde M, Jouy N, Mitchell V, Franck T, Donnay I, Lejeune J.P, 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.
- Young S.A, Miyata H, Satouh Y, Aitken R.J, Baker M.A, Ikawa M. CABYR is essential for fibrous sheath integrity and progressive motility in mouse spermatozoa. J. Cell Sci. 2016;129:4379–4387.
- Tseng Y.T, Hsia J.Y, Chen C.Y, Lin N.T, Chong P.C, Yang C.Y. Expression of the sperm fibrous sheath protein CABYR in human cancers and identification of α-enolase as an interacting partner of CABYR-a. Oncol. Rep. 2011;25:1169–1175.
- Hoyer-Fender S. Development of the Connecting Piece in ODF1-Deficient Mouse Spermatids. Int. J. Mol. Sci. 2022;23:10280.
- Lerer-Goldshtein T, Bel S, Shpungin S, Pery E, Motro B, Goldstein R.S, Bar-Sheshet S.I, Breitbart H, Nir U. TMF/ARA160: A key regulator of sperm development. Dev. Biol. 2010;348:12–21.
- Dacheux J.L, Belleannée C, Guyonnet B, Labas V, Teixeira-Gomes A.P, Ecroyd H, Druart X, Gatti J.L, Dacheux F. The contribution of proteomics to understanding epididymal maturation of mammalian spermatozoa. Syst. Biol. Reprod. Med. 2012;58:197–210.
- Agarwal A, Bertolla R.P, Samanta L. Sperm proteomics: Potential impact on male infertility treatment. Expert. Rev. Proteom. 2016;13:285–296.
- Peña F.J, Martín-Cano F.E, Becerro-Rey L, Ortega-Ferrusola C, Gaitskell-Phillips G, da Silva-Álvarez E, Gil M.C. Proteomics is advancing the understanding of stallion sperm biology. Proteomics 2024;24:e2300522.
- Shen H.P, Dong X, Li Z.B, Wu J.Z, Zheng C.M, Hu X.J, Qian C, Wang S.P, Zhao Y.L, Li J.C. Protein Profiles and Novel Molecular Biomarkers of Schizophrenia Based on 4D-DIA Proteomics. J. Proteome Res. 2024;23:2376–2385.
- Jiao X, Li X, Zhang N, Yan B, Huang J, Zhao J, Zhang H, Chen W, Fan D. Solubilization of fish myofibrillar proteins in NaCl and KCl solutions: A DIA-based proteomics analysis. Food Chem. 2024;445:138662.
- Chen M, Zhu P, Wan Q, Ruan X, Wu P, Hao Y, Zhang Z, Sun J, Nie W, Chen S. High-Coverage Four-Dimensional Data-Independent Acquisition Proteomics and Phosphoproteomics Enabled by Deep Learning-Driven Multidimensional Predictions. Anal. Chem. 2023;95:7495–7502.
- Na L, Xu M, Chen J.L, Chen G.J, Sun J, Zhang Q, Li J.Q, Guo X.L, Zuo Z.F, Liu X.Z. 4D-DIA quantitative proteomics revealed the core mechanism of diabetic retinopathy after berberine treatment. Eur. J. Pharmacol. 2023;958:175947.
- Cao Q, Zhu H, Xu W, Zhang R, Wang Y, Tian Z, Yuan Y. Predicting the efficacy of glucocorticoids in pediatric primary immune thrombocytopenia using plasma proteomics. Front. Immunol. 2023;14:1301227.
- Xie H, Zhang Y, Zhu Z, Wei J, Ainiwaer G, Ge W. Plasma Proteomic Analysis Based on 4D-DIA Evaluates the Clinical Response to Imrecoxib in the Early Treatment of Osteoarthritis. Rheumatol. Ther. 2024;11:269–283.
- Sun P, Zhang G, Xian M, Zhang G, Wen F, Hu Z, Hu J. Proteomic Analysis of Frozen-Thawed Spermatozoa with Different Levels of Freezability in Dairy Goats. Int. J. Mol. Sci. 2023;24:15550.
- Luo M, Su T, Wang S, Chen J, Lin T, Cheng Q, Chen Y, Gong M, Yang H, Li F. Proteomic Landscape of Human Spermatozoa: Optimized Extraction Method and Application. Cells 2022;11:4064.
- Kaya A, Dogan S, Vargovic P, Kutchy N.A, Ross P, Topper E, Oko R, van der Hoorn F, Sutovsky P, Memili E. Sperm proteins ODF2 and PAWP as markers of fertility in breeding bulls. Cell Tissue Res. 2022;387:159–171.
- Zang S, Yang X, Ye J, Mo X, Zhou G, Fang Y. Quantitative phosphoproteomics explain cryopreservation-induced reductions in ram sperm motility. J. Proteom. 2024;298:105153.
- Zmudzinska A, Wisniewski J, Mlynarz P, Olejnik B, Mogielnicka-Brzozowska M. Age-Dependent Variations in Functional Quality and Proteomic Characteristics of Canine (Canis lupus familiaris) Epididymal Spermatozoa. Int. J. Mol. Sci. 2022;23:9143.
- Hitit M, Özbek M, Ayaz-Guner S, Guner H, Oztug M, Bodu M, Kirbas M, Bulbul B, Bucak M.N, Ataman M.B. Proteomic fertility markers in ram sperm. Anim. Reprod. Sci. 2021;235:106882.
- Catalán J, Yánez-Ortiz I, Martínez-Rodero I, Mateo-Otero Y, Nolis P, Yeste M, Miró J. Comparison of the metabolite profile of donkey and horse seminal plasma and its relationship with sperm viability and motility. Res. Vet. Sci. 2023;165:105046.
- Podico G, Bittar J.H, Loux S.C, Souza F.F, Canisso I.F. The interaction between seminal plasma, sperm, and endometrium in inter- and intra-species breeding in equids. Reproduction 2024;167:e230472.
- Mogielnicka-Brzozowska M, Fraser L, Dziekońska A, Gackowska K, Sobiewska M, Kuzborska A, Majewska A.M, Filipowicz K, Kordan W. Identification of proteoforms of albumin and kallikrein in stallion seminal plasma and their correlations with sperm motility. Pol. J. Vet. Sci. 2019;22:227–235.
- Vicens A, Borziak K, Karr T.L, Roldan E.R.S, Dorus S. Comparative Sperm Proteomics in Mouse Species with Divergent Mating Systems. Mol. Biol. Evol. 2017;34:1403–1416.
- Bae J.W, Hwang J.M, Lee W.J, Kim D.H, Yi J.K, Ha J.J, Oh D.Y, Kwon W.S. Application of sperm motion kinematics and motility-related proteins for prediction of male fertility. Theriogenology 2024;218:223–230.
- Griffin R.A, Swegen A, Baker M, Aitken R.J, Skerrett-Byrne D.A, Silva Rodriguez A, Martín-Cano F.E, Nixon B, Peña F.J, Delehedde M. Mass spectrometry reveals distinct proteomic profiles in high- and low-quality stallion spermatozoa. Reproduction 2020;160:695–707.
- Xu Y, Han Q, Ma C, Wang Y, Zhang P, Li C, Cheng X, Xu H. Comparative Proteomics and Phosphoproteomics Analysis Reveal the Possible Breed Difference in Yorkshire and Duroc Boar Spermatozoa. Front. Cell Dev. Biol. 2021;9:652809.
- Bisconti M, Simon J.F, Grassi S, Leroy B, Martinet B, Arcolia V, Isachenko V, Hennebert E. Influence of Risk Factors for Male Infertility on Sperm Protein Composition. Int. J. Mol. Sci. 2021;22:13164.
- Liu X, Chen W, Huang B, Wang X, Peng Y, Zhang X, Chai W, Khan M.Z, Wang C. Advancements in copy number variation screening in herbivorous livestock genomes and their association with phenotypic traits. Front. Vet. Sci. 2023;10:1334434.
- Dong T, Liang Y, Chen H, Li Y, Li Z, Gao X. Quantitative proteomics revealed protein biomarkers to distinguish malignant pleural effusion from benign pleural effusion. J. Proteom. 2024;302:105201.
- He Y, Li H, Zhang Y, Hu J, Shen Y, Feng J, Zhao X. Comparative Analysis of Mitochondrial Proteome Reveals the Mechanism of Enhanced Ram Sperm Motility Induced by Carbon Ion Radiation After In Vitro Liquid Storage. Dose Response 2019;17:1559325818823998.
- Perez-Patiño C, Barranco I, Li J, Padilla L, Martinez E.A, Rodriguez-Martinez H, Roca J, Parrilla I. Cryopreservation Differentially Alters the Proteome of Epididymal and Ejaculated Pig Spermatozoa. Int. J. Mol. Sci. 2019;20:1791.
- Pérez-Patiño C, Li J, Barranco I, Martínez E.A, Rodriguez-Martínez H, Roca J, Parrilla I. The proteome of frozen-thawed pig spermatozoa is dependent on the ejaculate fraction source. Sci. Rep. 2019;9:705.
- Gacem S, Valverde A, Catalán J, Yánez Ortiz I, Soler C, Miró J. A New Approach of Sperm Motility Subpopulation Structure in Donkey and Horse. Front. Vet. Sci. 2021;8:651477.
- Miró J, Lobo V, Quintero-Moreno A, Medrano A, Peña A, Rigau T. Sperm motility patterns and metabolism in Catalonian donkey semen. Theriogenology 2005;63:1706–1716.
- Swegen A, Curry B.J, Gibb Z, Lambourne S.R, Smith N.D, Aitken R.J. Investigation of the stallion sperm proteome by mass spectrometry. Reproduction 2015;149:235–244.
- Yu J, Liu H, Li X, Ge S, Zhao X, Ji C, Wang Y, Wang Z, Dang R, Zhao F. TMT-based comparative proteomic analysis of Dezhou donkey spermatozoa related to freezability. J. Proteom. 2023;273:104793.
- Wei H, Zhang X, Wang C, Wang J, Li T, Chen S, Li H, Wang B. A pathogenic AKAP4 variant, p.R429H, causes male in/subfertility in humans and mice. Clin. Transl. Med. 2023;13:e1463.
- de Almeida A.B.M, Hidalgo M.M.T, de Moraes F.L.Z, Trautwein L.G.C, de Fátima Schnitzer J, Silva L, Rizzoto G, Ferreira J.C.P, Martins M.I.M. The proAKAP4 concentrations in Nelore bull sperm and their relation to FTAI conception rate results. Anim. Reprod. Sci. 2022;247:107156.
- Dordas-Perpinyà M, Yanez-Ortiz I, Sergeant N, Mevel V, Bruyas J.F, Catalán J, Delehedde M, Briand-Amirat L, Miró J. ProAKAP4 Concentration Is Related to Sperm Motility and Motile Sperm Subpopulations in Frozen-Thawed Horse Semen. Animals 2022;12:3417.
- Ashwitha A, Ramesha K.P, Ramesh P, Kootimole C.N, Devadasan M.J, Ammankallu S, Jeyakumar S, Kumaresan A, Veerappa V.G, Das D.N. Quantitative proteomics profiling of spermatozoa and seminal plasma reveals proteins associated with semen quality in Bos indicus bulls. J. Proteom. 2023;273:104794.
- Liang Z, Dai C, He F, Wang Y, Huang Y, Li H, Wu Y, Hu Y, Xu K. AKAP3-mediated type I PKA signaling is required for mouse sperm hyperactivation and fertility. Biol. Reprod. 2024;110:684–697.
- Naletova I, Schmalhausen E, Tomasello B, Pozdyshev D, Attanasio F, Muronetz V. The role of sperm-specific glyceraldehyde-3-phosphate dehydrogenase in the development of pathologies-from asthenozoospermia to carcinogenesis. Front. Mol. Biosci. 2023;10:1256963.
- Zhu Z.J, Wang Y.Z, Wang X.B, Yao C.C, Zhao L.Y, Zhang Z.B, Wu Y, Chen W, Li Z. Novel mutation in ODF2 causes multiple morphological abnormalities of the sperm flagella in an infertile male. Asian J. Androl. 2022;24:463–472.
- Bu Y, Wang P, Li S, Li L, Zhang S, Wei H. Semen Protein CRISP3 Promotes Reproductive Performance of Boars through Immunomodulation. Int. J. Mol. Sci. 2024;25:2264.
- Oud M.S, Okutman Ö, Hendricks L.A.J, de Vries P.F, Houston B.J, Vissers L, O’Bryan M.K, Ramos L, Chemes H.E, Viville S. Exome sequencing reveals novel causes as well as new candidate genes for human globozoospermia. Hum. Reprod. 2020;35:240–252.
- Frintrop L, Wiesehöfer C, Stoskus A, Hilken G, Dubicanac M, von Ostau N.E, Rode S, Elgeti J, Dankert J.T, Wennemuth G. cAMP and the Fibrous Sheath Protein CABYR (Ca(2+)-Binding Tyrosine-Phosphorylation-Regulated Protein) Is Required for 4D Sperm Movement. Int. J. Mol. Sci. 2022;23:10607.
- Moustakli E, Zikopoulos A, Sakaloglou P, Bouba I, Sofikitis N, Georgiou I. Functional association between telomeres, oxidation and mitochondria. Front. Reprod. Health. 2023;5:1107215.
- Shimada K, Lu Y, Ikawa M. Disruption of testis-enriched cytochrome c oxidase subunit COX6B2 but not COX8C leads to subfertility. Exp. Anim. 2024;73:1–10.
- Charron Y, Willert J, Lipkowitz B, Kusecek B, Herrmann B.G, Bauer H. Two isoforms of the RAC-specific guanine nucleotide exchange factor TIAM2 act oppositely on transmission ratio distortion by the mouse t-haplotype. PLoS Genet. 2019;15:e1007964.
- Tardif S, Brady H.A, Breazeale K.R, Bi M, Thompson L.D, Bruemmer J.E, Bailey L.B, Hardy D.M. Zonadhesin D3-polypeptides vary among species but are similar in Equus species capable of interbreeding. Biol. Reprod. 2010;82:413–421.
- Chauvin T, Xie F, Liu T, Nicora C.D, Yang F, Camp D.G. 2nd, Smith R.D, Roberts K.P. A systematic analysis of a deep mouse epididymal sperm proteome. Biol. Reprod. 2012;87:141.
- Gimeno-Martos S, González-Arto M, Casao A, Gallego M, Cebrián-Pérez J.A, Muiño-Blanco T, Pérez-Pé R. Steroid hormone receptors and direct effects of steroid hormones on ram spermatozoa. Reproduction 2017;154:469–481.
- Amaral A, Lourenço B, Marques M, Ramalho-Santos J. Mitochondria functionality and sperm quality. Reproduction 2013;146:R163–R174.
- Zhang H.Y, Mu Y, Chen P, Liu D.D, Chen K.H, Yu Q, He J, Sun F, Xing J.P, Tang K.F. Metabolic enzyme gene polymorphisms predict the effects of antioxidant treatment on idiopathic male infertility. Asian J. Androl. 2022;24:430–435.
- Dias G.M, López M.L, Ferreira A.T, Chapeaurouge D.A, Rodrigues A, Perales J, Retamal C.A. Thiol-disulfide proteins of stallion epididymal spermatozoa. Anim. Reprod. Sci. 2014;145:29–39.
- Gaitskell-Phillips G, Martín-Cano F.E, da Silva-Álvarez E, Tapia J.A, Silva A, Gil M.C, Ortega-Ferrusola C, Peña F.J. Phosphoproteomics for the identification of new mechanisms of cryodamage: The role of SPATA18 in the control of stallion sperm function. Biol. Reprod. 2023;108:324–337.
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