We have identified a region in the coding sequence (CRAS) of two replication-dependent histone genes, a H2a.2 and a H3.2, the deletion of which causes a 20-fold drop in expression. In vivo expression data obtained after transfection of in-frame oligonucleotide-directed deletions in the H3.2 CRAS show that there are multiple areas in the CRAS which act to increase expression of the intact gene. DNAase I protection of a sequence designated the CRAS alpha box is present in the CRAS of four classes of histone genes--H2a, H2b, H3 and H4. Deletion of the alpha box causes a 5-fold drop in expression of the H3.2 gene. The comparable "CRAS" region of a H3.3 gene, a nonreplication-dependent variant, was used as a non-specific competitor. Although the coding region is highly conserved among classes of histone genes, the H3.3 "alpha box" sequence contains 5 base changes out of 7. UV crosslinking of the protein bound H3.2 CRAS alpha sequence identifies a protein doublet migrating at 80 and 90 kD on SDS-polyacrylamide gels. Binding to the alpha box is regulated by the phosphorylation state of the nuclear protein that binds the alpha sequence. Dephosphorylation of the CRAS alpha protein is necessary for binding to the target sequence. The role of the CRAS-binding proteins in cell cycle regulation of histone gene expression was studied by preparing G1 and S phase nuclear extracts from synchronous populations of CHO cells. Binding of CRAS alpha protein to duplex oligonucleotides containing the consensus sequence is greatly elevated in S phase compared to G1. / Source: Dissertation Abstracts International, Volume: 55-04, Section: B, page: 1295. / Major Professor: William F. Marzluff. / Thesis (Ph.D.)--The Florida State University, 1994.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_77155 |
| Contributors | Bowman, Tammy Lynn., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 220 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
Page generated in 0.0024 seconds