title: Mapping of post-translational modifications of spermatid-specific linker histone H1-like protein, HILS1.
abstract: In mammalian spermiogenesis, haploid round spermatids undergo dramatic biochemical and morphological changes and transform into motile mature spermatozoa. A majority of the histones are replaced by transition proteins during mid-spermiogenesis and later replaced by protamines, which occupy the sperm chromatin. In mammals, 11 linker histone H1 subtypes have been reported. Among them, H1t, HILS1, and H1T2 are uniquely expressed in testis, with the expression of HILS1 and H1T2 restricted to spermiogenesis. However, there is a lack of knowledge about linker histone role in the nuclear reorganization during mammalian spermiogenesis. Here, we report a method for separation of endogenous HILS1 protein from other rat testis linker histones by reversed-phase high-performance liquid chromatography (RP-HPLC) and identification of 15 novel post-translational modifications of HILS1, which include lysine acetylation and serine/threonine/tyrosine phosphorylation sites. Immunofluorescence studies demonstrate the presence of linker histone HILS1 and HILS1Y78p during different steps of spermiogenesis from early elongating to condensing spermatids.
authors.affiliation: Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O. Bangalore 560064, India.
authors.forename: Laxmi N
authors.initials: LN
authors.lastname: Mishra
authors.affiliation: Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O. Bangalore 560064, India.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Gupta
authors.affiliation: Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O. Bangalore 560064, India. Electronic address: mrsrao@jncasr.ac.in.
authors.forename: Satyanarayana M R
authors.initials: SM
authors.lastname: Rao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D002868:Chromosomal Proteins, Non-Histone / Q000737:chemistry* / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013087:Spermatids / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; C000610306:HILS1 protein, rat
keywords: Chromatin remodeling; HILS1; Linker histones; Mass spectrometry; Post-translational modifications; Spermiogenesis