Direct regulation of beta3-integrin subunit gene expression by HOXA10 in endometrial cells.
Estrogen and progesterone regulate HOXA10 expression in the endometrium, where HOXA10 is necessary for implantation. The integrins are also involved in early embryo-endometrial interactions. Here we show that HOXA10 directly regulates beta3-integrin subunit expression in the endometrium, likely mediating the effect of sex steroids on beta3-integrin expression. beta3-Integrin expression was decreased in endometrium shown to have low HOXA10 expression. beta3-Integrin mRNA levels were increased in endometrial adenocarcinoma cells (Ishikawa) transfected with pcDNA3.1/HOXA10, and decreased in cells treated with HOXA10 antisense. Seven consensus HOXA10 binding sites were identified 5' of the beta3-integrin gene. Direct binding of HOXA10 protein to four sites was demonstrated by EMSA. Reporter gene expression increased in BT-20 cells cotransfected with pcDNA3.1/ HOXA10 and pGL3-promoter vector containing region F (encompassing all seven HOXA10 consensus sites). A 41-bp segment (Region A) showed highest affinity binding to HOXA10 protein. Increased reporter expression, equal in magnitude to that obtained with Region F, was obtained with Region A. HOXA10 protein binding within Region A was localized by deoxyribonuclease I footprinting. beta3-Integrin expression was directly up-regulated by HOXA10 through a 41-bp 5'-regulatory element. Sex steroids regulate the expression of endometrial beta3-integrin through a pathway involving HOXA10.
Daftary
Gaurang S
GS
Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06520-8063, USA.
Troy
Patrick J
PJ
Bagot
Catherine N
CN
Young
Steven L
SL
Taylor
Hugh S
HS
D000230:Adenocarcinoma / Q000737:chemistry / Q000378:metabolism; D000328:Adult; D015703:Antigens, CD / Q000235:genetics*; D001483:Base Sequence; D001665:Binding Sites; D015152:Blotting, Northern; D016384:Consensus Sequence; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D016889:Endometrial Neoplasms / Q000737:chemistry / Q000378:metabolism; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D017930:Genes, Reporter; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D039661:Integrin beta3; D008969:Molecular Sequence Data; D010980:Platelet Membrane Glycoproteins / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis; D012045:Regulatory Sequences, Nucleic Acid; D014162:Transfection
D015703:Antigens, CD; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins; D039661:Integrin beta3; D010980:Platelet Membrane Glycoproteins; D012333:RNA, Messenger; C092119:Hoxa10 protein, mouse; D004247:DNA