Isolation and characterization of the spermatid-specific Smrp1 gene encoding a novel manchette protein.
The manchette, which is the structure that appears around the nuclei of elongated spermatids, is assumed to be involved in nuclear shaping during spermiogenesis and the transport of various proteins between the nucleus and sperm tail. In this report, we describe the molecular cloning and characterization of a mouse spermatid-specific manchette-related protein 1 (Smrp1) from a spermatid-specific subtracted mouse testis cDNA library. The isolated Smrp1 cDNA clones could be divided into three variants based on sequence analysis. Computer-assisted analysis showed that these variants were splice variants from a single locus of the mouse genome. The three putative proteins consisted of 296, 260, and 175 amino acids, respectively. Although 155 amino acids of the N terminus were common to the three proteins, they were distinguished by their C-terminal regions. Western blot analyses using specific antisera showed that SMRP1 expression was specific to the testes and that only the 261-amino-acid form was translated into protein. Immunohistochemistry revealed that SMRP1 was localized to the cytoplasm of step 9-12 elongated spermatids. The protein appeared in a cap formation that covered the caudal sides of the elongated nuclei. This localization pattern coincided with that of the manchette. SMRP1 may play an important role as a functional protein that co-operates with manchette proteins.
Matsuoka
Yasuhiro
Y
Department of Urology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.
Miyagawa
Yasushi
Y
Tokuhiro
Keizo
K
Kitamura
Kouichi
K
Iguchi
Naoko
N
Maekawa
Mamiko
M
Takahashi
Tohru
T
Tsujimura
Akira
A
Matsumiya
Kiyomi
K
Okuyama
Akihiko
A
Nishimune
Yoshitake
Y
Tanaka
Hiromitsu
H
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D014644:Genetic Variation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification; D013087:Spermatids / Q000378:metabolism*; D013091:Spermatogenesis / Q000235:genetics; D013737:Testis / Q000033:anatomy & histology / Q000378:metabolism; D014162:Transfection
D018076:DNA, Complementary; D011506:Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins