DOI 10.1095/biolreprod.103.023580 Molecular Characterization of Heat Shock-Like Factor Encoded on the Human

Azoospermia and oligospermia are major causes of male in-fertility. 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 hu-man 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 hu-man X chromosome and a murine HSFY-like sequence (m-HSFYL), 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, re-spectively. Comparison of the presumed DNA-binding domains unveiled that the three HSF-like factors, HSFY, LW-1, and m