TY - JOUR
T1 - Cloning and characterization of the human β4-integrin gene promoter and enhancers
AU - Takaoka, Asako Suzuki
AU - Yamada, Tesshi
AU - Gotoh, Masahiro
AU - Kanai, Yae
AU - Imai, Kohzoh
AU - Hirohashi, Setsuo
PY - 1998/12/11
Y1 - 1998/12/11
N2 - The cell-surface adhesion molecule α6β4-integrin is a receptor for laminins and a component of hemidesmosomes. β4-Integrin expression is restricted to proliferating basal keratinocytes in the epidermis and is suppressed when differentiation commences. Altered β4-integrin expression levels correlate significantly with the aggressive behavior of cancers. In order to clarify the mechanisms that regulate transcription of the β4- integrin gene, we cloned its 5'-flanking region. This 5'-flanking region was found to have a high G + C content and not to contain either TATA or CAAT boxes. Nested delimitation and reporter analyses mapped a basal promoter to nucleotides -106 to +105, surrounding the most proximal transcription initiation site. Gel retardation and mutational analyses revealed that cooperation between AP1 and Ets, interacting with other factors, mediated the promoter activity. In addition to the promoter element, enhancer activity was found in the first intron (+1905/+3933) and in a sequence upstream of the promoter region (-414/-107). These findings should facilitate our understanding of the regulation of β4-integrin gene expression in processes such as cell growth and differentiation, apoptosis, and cancer development and metastasis.
AB - The cell-surface adhesion molecule α6β4-integrin is a receptor for laminins and a component of hemidesmosomes. β4-Integrin expression is restricted to proliferating basal keratinocytes in the epidermis and is suppressed when differentiation commences. Altered β4-integrin expression levels correlate significantly with the aggressive behavior of cancers. In order to clarify the mechanisms that regulate transcription of the β4- integrin gene, we cloned its 5'-flanking region. This 5'-flanking region was found to have a high G + C content and not to contain either TATA or CAAT boxes. Nested delimitation and reporter analyses mapped a basal promoter to nucleotides -106 to +105, surrounding the most proximal transcription initiation site. Gel retardation and mutational analyses revealed that cooperation between AP1 and Ets, interacting with other factors, mediated the promoter activity. In addition to the promoter element, enhancer activity was found in the first intron (+1905/+3933) and in a sequence upstream of the promoter region (-414/-107). These findings should facilitate our understanding of the regulation of β4-integrin gene expression in processes such as cell growth and differentiation, apoptosis, and cancer development and metastasis.
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U2 - 10.1074/jbc.273.50.33848
DO - 10.1074/jbc.273.50.33848
M3 - Article
C2 - 9837976
AN - SCOPUS:0032509477
VL - 273
SP - 33848
EP - 33855
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 50
ER -