|
|
||||||||
Department of Developmental Biochemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
Transcription stimulator S-II relieves RNA polymerase II (RNAPII) from transcription elongation arrest. Mice lacking the S-II gene (S-II KO mice) die at mid-gestation with impaired erythroblast differentiation, and have decreased expression of the Bcl-x gene. To understand a role of S-II in Bcl-x gene expression, we examined the distribution of transcription complex on the Bcl-x gene in S-II KO mice. The amount of RNAPII at intron 2 of the Bcl-x gene was decreased in S-II KO mice, whereas recruitment of transcription initiation factor TFIIB and RNAPII to the promoter was not decreased. Consistently, in vitro transcription analysis revealed the presence of a transcription arrest site in the Bcl-x gene intron 2, and transcription arrest at this site was overcome by S-II. Furthermore, histone acetylation on the coding region of the Bcl-x gene was decreased in S-II KO mice. In the βmajor-globin gene, whose expression was also decreased in S-II KO mice, there were no changes in RNAPII distribution or histone acetylation, but the amount of histone H3 occupying the coding region was increased. These results suggest that S-II is involved in transcription of the Bcl-x and βmajor-globin gene during erythroblast differentiation, by relieving transcription arrest or affecting histone modification on chromatin template.
* Correspondence: sekimizu{at}mol.f.u-tokyo.ac.jp
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | ADVANCED SEARCH | TABLE OF CONTENTS |