Transcriptional analysis of the 5'-noncoding region of the human involucrin gene.
Human involucrin whose gene transcription is directed by a 2456-nucleotide (nt) 5'-noncoding region is a structural component of the epithelial cornified layer. Transient transfection assays demonstrated that this region is transcriptionally active in multiplying keratinocytes and is enhanced by 2 mM CaCl2 treatment. Calcium-independent transcriptional activity and the interaction with the AP-1 transcriptional factor was located on the proximal part (nt -159 to -1) of the 5'-noncoding region. However, CaCl2 responsiveness was mapped to a distal 1185-nt fragment (nt -2456 to -1272). Moreover, this fragment potentiated the Herpes simplex thymidine kinase promoter in normal keratinocytes and is responsive to calcium treatment in a cell type-specific manner. Interestingly, the absence of a 491-nt fragment located between the two enhancer domains (nt -651 to -160) resulted in transcriptional activation in multiplying keratinocytes. This fragment interacts with AP-1 and the YY1 transcriptional silencer. It is concluded that human involucrin 5'-noncoding region contains at least three regulatory domains, a distal CaCl2-responsive enhancer, a putative transcriptional silencer (that interacts with AP-1 and YY1), and a proximal enhancer/promoter (that interacts with AP-1). Thus, this study demonstrates the presence of particular transcriptional factors can potentially regulate the human involucrin expression.
Lopez-Bayghen
E
E
Departamento de Genetica y Biologia Molecular, Centro de Investigacion y Estudios Avanzados del Instituto Politecnico Nacional, Mexico, Distrito Federal, Mexico.
Vega
A
A
Cadena
A
A
Granados
S E
SE
Jave
L F
LF
Gariglio
P
P
Alvarez-Salas
L M
LM
D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002478:Cells, Cultured; D004247:DNA; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D050981:Erythroid-Specific DNA-Binding Factors; D006367:HeLa Cells; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011498:Protein Precursors / Q000235:genetics*; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection; D050986:YY1 Transcription Factor
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D011498:Protein Precursors; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C494698:YY1 protein, human; C032253:involucrin; D004247:DNA