S-phase-specific transcription regulatory elements are present in a replication-independent testis-specific H2B histone gene.
The testis-specific H2B histone (TH2B) gene is expressed in pachytene spermatocytes during meiotic prophase I in the absence of any significant DNA synthesis. Unlike somatic histones, synthesis of testis-specific histones is not affected by inhibitors of DNA synthesis. A genomic rat TH2B gene was cloned by using a DNA fragment derived from TH2B cDNA as a probe. Expression of the cloned TH2B was investigated by gene transfer experiments. From these studies, we found that the 5' upstream region of the cloned TH2B gene contained S-phase-specific transcription elements which regulated expression of a reporter gene in an S-phase-specific manner. The S-phase-regulatory element was found to be located in two regions containing CCAAT elements between -153 and -110 base pairs (bp) and an octamer element (ATTTGCAT) between -109 and -84 bp. The two regions were required for a maximal stimulation of transcription of the cloned TH2B gene in S phase. On the other hand, only the octamer element was reported be important for the S-phase-specific transcription of human H2B gene. Since the synthesis of the TH2B histone is independent of DNA synthesis and specific for pachytene spermatocytes in vivo, the presence of the S-phase-specific transcription regulatory elements in the TH2B gene is surprising.
Hwang
I
I
Department of Biochemistry, University of North Carolina, Chapel Hill 27599-7260.
Chae
C B
CB
D000818:Animals; D001483:Base Sequence; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004261:DNA Replication; D005786:Gene Expression Regulation; D005809:Genes, Regulator; D006657:Histones / Q000235:genetics*; D007399:Interphase; D008297:Male; D008969:Molecular Sequence Data; D051381:Rats; D013090:Spermatocytes / Q000166:cytology / Q000378:metabolism*; D014158:Transcription, Genetic
D006657:Histones; D004247:DNA; D015500:Chloramphenicol O-Acetyltransferase