Back to Search
Start Over
Transcriptional regulation of OCI-5/Glypican 3: elongation control of confluence-dependent induction.
- Source :
-
Oncogene . 9/25/97, Vol. 15 Issue 13, p1535. 10p. - Publication Year :
- 1997
-
Abstract
- OCI-5/Glypican 3, a member of the glypican family of proteoglycans, is the defective gene in the Simpson-Golabi-Behmel overgrowth syndrome. OCI-5 expression is developmentally regulated in the intestinal epithelium, and the mechanism of its regulation was studied in the rat intestinal epithelial cell line IEC-18. A large induction of OCI-5 transcript and protein was observed at high cell density. Among other glypican family members, κ-glypican also exhibited a confluence-dependent induction in select cell types. Nuclear run-on analysis indicated that cell-density regulation of OCI-5 occurs at the level of transcription. The rat and mouse OCI-5 promoters were cloned and found to be highly conserved, located within CpG islands and contain regions of alternating purine and pyrimidine residues. No TATA-box or recognizable INR element was observed. Consensus binding sites for AP-2, SP-1, zeste and NF-1/CTF are conserved across human, mouse and rat promoters. 5′ deletion mapping of the rat promoter identified regions which enhance and repress promoter activity, with no apparent confluence-dependence or tissue-specificity. Nuclear run-on analysis probing different regions of the gene suggests that elongation control plays a role in the induction of OCI-5 by confluence. [ABSTRACT FROM AUTHOR]
- Subjects :
- *PROTEOGLYCANS
*INTESTINES
*TRANSCRIPTION factors
Subjects
Details
- Language :
- English
- ISSN :
- 09509232
- Volume :
- 15
- Issue :
- 13
- Database :
- Academic Search Index
- Journal :
- Oncogene
- Publication Type :
- Academic Journal
- Accession number :
- 8919226
- Full Text :
- https://doi.org/10.1038/sj.onc.1201325