title: Insights into the lysine acetylproteome of human sperm.
abstract: Protein lysine acetylation is a dynamic and reversible post-modification that is known to play diverse functions in eukaryotes. Nevertheless, the composition and function of non-histone lysine acetylation in gametes remain unknown. In humans, only capacitated sperm have the capacity to fertilize an egg. In the present study, we found complex composition of lysine acetylated proteins in capacitated human sperm. In vitro fertilization inhibition assay by anti-acetyllysine antibody showed essential roles of lysine acetylation in fertilization. And inhibition of lysine deacetylases, the histone deacetylases, by trichostatin A and nicotinamide, could significantly suppress sperm motility. After immunopurification enrichment of acetylpeptides with anti-acetyllysine antibody and high-throughput liquid chromatography-tandem mass spectrometry identification, we characterized 1206 lysine acetylated sites, corresponding to 576 lysine acetylated proteins in human capacitated sperm. Bioinformatics analysis showed that these proteins are associated with sperm functions, including motility, capacitation, acrosome reaction and sperm-egg interaction. Thus, lysine acetylation is expected to be an important regulatory mechanism for sperm functions. And our characterization of lysine acetylproteome could be a rich resource for the study of male fertility.
  
  
  CONCLUSIONS
  Mature sperm are almost transcriptionally and translationally silent, thus post-translational modifications play important roles in sperm functions. Till now, only two types of PTMs, phosphorylation and glycosylation, are well studied in normal human sperm based on large scale proteomics. In the present study, we established the acetylproteome of capacitated human sperm. Over 1000 lysine acetylated sites were identified. Bioinformatics analysis shows that lysine acetylated proteins participate in many biological events of sperm functions. We further provided functional data that the lysine acetylation is essential for sperm motility and fertilization using histone acetylase inhibitors and anti-acetyllysine antibody. These data can be strong evidences for the important function of lysine acetylation in human sperm.
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Guohai
authors.initials: G
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Yueshuai
authors.initials: Y
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China. Electronic address: guo_xuejiang@njmu.edu.cn.
authors.forename: Xuejiang
authors.initials: X
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China. Electronic address: shajh@njmu.edu.cn.
authors.forename: Jiahao
authors.initials: J
authors.lastname: Sha
mesh_terms: D000107:Acetylation; D020101:Acrosome Reaction / Q000187:drug effects / Q000502:physiology; D000328:Adult; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D008239:Lysine / Q000378:metabolism; D008297:Male; D020543:Proteome / Q000378:metabolism*; D013081:Sperm Motility / Q000187:drug effects / Q000502:physiology; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; D020543:Proteome; C012589:trichostatin A; D006655:Histone Deacetylases; D008239:Lysine
keywords: Acetylproteome; Capacitation; Human sperm; Lysine acetylation; Proteomics