title: Complementary DNA cloning and characterization of rat spergen-2, a spermatogenic cell-specific gene 2 encoding a 56-kilodalton nuclear protein bearing ankyrin repeat motifs.
abstract: Differential display in combination with a cDNA cloning approach were used to isolate a novel gene, spergen-2, which has an open reading frame of 1500 nucleotides and encodes a protein of 500 amino acids that contains ankyrin repeat motifs and a putative nuclear localization signal. Expression of spergen-2 is developmentally upregulated in testis. In situ hybridization revealed that spergen-2 mRNA is expressed in spermatocytes and round spermatids (steps 1-6). Immunohistochemical analysis with confocal laser-scanning microscopy demonstrated that spergen-2 protein is predominantly expressed in nuclei of late spermatocytes (stages IX-XIV) and spermatids (steps 1-11), indicating the restricted expression of spergen-2 during spermatogenesis. In nucleoplasm of spermatogenic cell nuclei, spergen-2 tends to localize in the interchromosome space with relatively low DNA density. These findings indicate a potential role of spergen-2 in spermatogenesis, especially in cell differentiation from late pachytene spermatocytes to spermatids or in early spermatid differentiation.
authors.affiliation: Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka 812-8581, Japan. iidahiro@agr.kyushu-u.ac.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iida
authors.forename: Aiko
authors.initials: A
authors.lastname: Urasoko
authors.forename: Masamichi
authors.initials: M
authors.lastname: Doiguchi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Mōri
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Toshimori
authors.forename: Yosaburo
authors.initials: Y
authors.lastname: Shibata
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017487:Ankyrins / Q000096:biosynthesis* / Q000235:genetics; D015152:Blotting, Northern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000096:biosynthesis* / Q000235:genetics; D005982:Glutathione Transferase / Q000378:metabolism; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics* / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012671:Seminiferous Tubules / Q000378:metabolism; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000166:cytology*; D015854:Up-Regulation
chemical_list: C483116:Ankrd36 protein, rat; D017487:Ankyrins; D018076:DNA, Complementary; D009687:Nuclear Proteins; D012333:RNA, Messenger; D005982:Glutathione Transferase