E. Lopezbayghen et al., TRANSCRIPTIONAL ANALYSIS OF THE 5'-NONCODING REGION OF THE HUMAN INVOLUCRIN GENE, The Journal of biological chemistry, 271(1), 1996, pp. 512-520
Human involucrin whose gene transcription is directed by a 2456-nucleo
tide (nt) 5'-noncoding region is a structural component of the epithel
ial cornified layer, Transient transfection assays demonstrated that t
his region is transcriptionally active in multiplying keratinocytes an
d is enhanced by 2 mM CaCl2 treatment, Calcium-independent transcripti
onal 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 f
ragment (nt -2456 to -1272), Moreover, this fragment potentiated the H
erpes simplex thymidine kinase promoter in normal keratinocytes and is
responsive to calcium treatment in a cell type-specific manner, Inter
estingly, the absence of a 491-nt fragment located between the two enh
ancer domains (nt -651 to -160) resulted in transcriptional activation
in multiplying keratinocytes. This fragment interacts with AP-1 and t
he YY1 transcriptional silencer, It is concluded that human involucrin
5'-noncoding region contains at least three regulatory domains, a dis
tal CaCl2-responsive enhancer, a putative transcriptional silencer (th
at interacts with AP-1 and YY1), and a proximal enhancer/promoter (tha
t interacts with AP-1), Thus, this study demonstrates the presence of
particular transcriptional factors can potentially regulate the human
involucrin expression.