Analysis of the tissue-specific promoter of the MUC1 gene.
J Biol Chem
; 268(13): 9917-26, 1993 May 05.
Article
de En
| MEDLINE
| ID: mdl-8387509
ABSTRACT
The 5'-sequences flanking the human MUC1 gene have been analyzed for their ability to direct expression of a reporter gene (the chloramphenicol acetyltransferase gene (CAT)) in cell lines that normally express or do not express the MUC1 gene. A construct containing 2.9 kilobase pairs of MUC1 5'-flanking sequence sequence showed expression of CAT in breast and pancreatic cell lines but not in the non-epithelial cell lines HT-1080, SK23, and HTB96. Deletion analysis showed that maximum expression was obtained in ZR-75 (breast cancer line) and HPAF (pancreatic cancer line) with only 743 base pairs of 5'-flanking sequence. Sequences within 1.6 kilobase pairs of the transcriptional start site showed enhancing activity in a vector carrying an enhancerless SV40 promoter. Analysis of proximal 5'-sequences in a promoterless CAT vector carrying the SV40 enhancer showed that sequences between -60 and -150 were crucial for tissue-specific expression. An Sp1 site at -99/-90 and an E box (E-MUC1) at -84/-64 in this region were shown by mutational analysis to play a role in the regulation of transcription. Gel shift analysis with oligonucleotides and nuclear extracts of ZR-75 showed protein binding to both of these sites. Sp1 binding activity was similar in ZR-75 and HT1080 cells, whereas binding of factors to the E-MUC1 oligonucleotide revealed quantitative and qualitative differences between epithelial and non-epithelial cells.
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Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Glycoprotéines membranaires
/
Régions promotrices (génétique)
/
Mucines
Type d'étude:
Qualitative_research
Limites:
Humans
Langue:
En
Journal:
J Biol Chem
Année:
1993
Type de document:
Article
Pays d'affiliation:
Royaume-Uni