Journal of Andrology, Vol. 25, No. 6, November/December 2004
Copyright © American Society of Andrology
Molecular Cloning of Rat Spergen-3, a Spermatogenic Cell-Specific Gene-3, Encoding a Novel 75-kDa Protein Bearing EF-Hand Motifs
HIROSHI IIDA*,
HARUHIRO YAMASHITA
,
MASAMICHI DOIGUCHI* AND
TAKANE KANEKO*
From the * Department of Zoology, Graduate School
of Agriculture, Kyushu University, Fukuoka, Japan;
Taisho Pharmaceutical Co, Ltd, Saitama,
Japan.
|
Correspondence to: Dr Hiroshi Iida, Laboratory of Zoology, Graduate School of
Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka 812-8581,
Japan (e-mail:
iidahiro{at}agr.kyushu-u.ac.jp). |
By use of differential display in combination with cDNA cloning approach,
we isolated a novel rat gene designated as Spergen-3, which has an open
reading frame of 2055-length nucleotides encoding a protein of 685 amino
acids. Spergen-3 gene is composed of 15 exons and mapped on chromosome 5q36,
and its mouse counterpart, which shares 85.5% identity to rat Spergen-3 at the
amino acid level, is mapped on chromosome 4E1. Spergen-3 encodes a 75-kDa
soluble protein bearing putative 2 EF-hand motifs, proline-repeat, and a
putative nuclear localization signal. Of the 2 EF-hand motifs in Spergen-3,
the second one seems to match the consensus sequence. Reverse
transcription-polymerase chain reaction analysis showed that the expression of
Spergen-3 is developmentally up-regulated and that it is exclusively expressed
in testis. In situ hybridization revealed that Spergen-3 mRNA was exclusively
expressed in haploid spermatids, but its signal was weak or undetectable in
spermatogonia, spermatocytes, and Sertoli cells as well as in interstitial
cells. We interpreted these data as a potential role of Spergen-3, a new
member of EF-hand family, in differentiation of haploid spermatids in
testis.
Key words: Spermatogenesis, spermiogenesis, spermatid, calcium-binding protein, differential display
Copyright © 2004 by The American Society of Andrology.
