Isolation and characterization of a novel cDNA encoding a DNA-binding protein (Hils1) specifically expressed in testicular haploid germ cells.
A cDNA encoding a protein homologous with histone H1 has been cloned from a haploid germ cell specific cDNA library. Deduced amino acid sequence (170 amino acids) showed 40% identity with histone H1 globular domain. Messenger RNA of the gene was observed exclusively in the testis, and was accumulated after post-natal day 23. Western blotting analysis showed that the protein encoded by this gene is about 19 kDa in molecular weight, and it was exclusively recovered from the nuclei of testicular germ cells. Immunohistochemical analysis showed that the protein was localized to the nuclei of round and elongating spermatids, consistent with the results of immunoblot analysis. Thus, the gene product was named Hils1 (histone H1 like protein in spermatids 1). In vitro DNA-binding experiments using DNA-cellulose mini-columns showed that Hils1 was able to bind to both double and single stranded-DNAs in a non-sequence-specific manner. These findings suggest that Hils1 may play an important role in the structural changes of spermatid nuclei, such as nuclear condensation, and gene regulation of haploid germ cell differentiation.
Iguchi
Naoko
N
Department of Science for Laboratory Animal Experimentation, Research Institute for Microbial Diseases, Osaka University, Suita City, Osaka, Japan.
Tanaka
Hiromitsu
H
Yomogida
Kentaro
K
Nishimune
Yoshitake
Y
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D002478:Cells, Cultured; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D006238:Haploidy; D006657:Histones / Q000235:genetics* / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D013087:Spermatids / Q000378:metabolism; D013737:Testis / Q000166:cytology* / Q000378:metabolism*; D014018:Tissue Distribution; D024363:Transcription Initiation Site
D018076:DNA, Complementary; D006657:Histones; D010446:Peptide Fragments; D012333:RNA, Messenger