Molecular characterization of heat shock-like factor encoded on the human Y chromosome, and implications for male infertility.
Azoospermia and oligospermia are major causes of male infertility. Some genes located on the Y chromosome are suggested as candidates. Recently, HSFY, which is similar to the HSF (heat shock transcription factor) family, has been mapped on the human Y chromosome as multicopies. However, newly available sequence data deposited at NCBI shows that only the HSFY gene located on Yq has a long open reading frame containing a HSF-type DNA-binding domain. HSFY is similar to LW-1 on the human X chromosome and a murine HSFY-like sequence (mHSFYL), 4933413G11Rik, on the mouse chromosome 1. LW-1 and mHSFYL have 53% and 70% homology to HSFY for amino acid sequences of their presumed DNA-binding domains, respectively. Comparison of the presumed DNA-binding domains unveiled that the three HSF-like factors, HSFY, LW-1, and mHSFYL, belong to a different class than conventional HSFs. When we screened for deletions on the Yq of males suffering from infertility, we found that HSFY was involved in interstitial deletions on the Y chromosomes for two azoospermic males who had DBY, USP9Y, and DAZ but did not have RBMY located on the AZFb. Expression analysis of HSFY, LW-1, and mHSFYL unveiled that they are expressed predominantly in testis. Furthermore, immunhistochemistry of HSFY in testis showed that its expression is restricted to both Sertoli cells and spermatogenic cells and that it exhibits a stage-dependent translocation from the cytoplasm to the nucleus in spermatogenetic cells during spermatogenesis. These results may suggest that deletion of HSFY is involved in azoospermia or oligospermia.
Shinka
Toshikatstu
T
Department of Human Genetics and Public Health, Graduate School of Proteomics, Faculty of Medicine, The University of Tokushima, Tokushima-City, 770-8503 Japan.
Sato
Yoko
Y
Chen
Gang
G
Naroda
Takushi
T
Kinoshita
Keigo
K
Unemi
Yukiko
Y
Tsuji
Keiko
K
Toida
Kazunori
K
Iwamoto
Teruaki
T
Nakahori
Yutaka
Y
D000328:Adult; D000595:Amino Acid Sequence; D015153:Blotting, Western; D002460:Cell Line; D041322:Chromosomes, Human, Y; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007248:Infertility, Male / Q000235:genetics*; D007424:Intracellular Fluid / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009845:Oligospermia / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013737:Testis / Q000378:metabolism; D014018:Tissue Distribution; D014157:Transcription Factors
D004268:DNA-Binding Proteins; C494708:HSFX1 protein, human; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins; D014157:Transcription Factors