Identification of the contact sites of a factor that interacts with motif i (alpha CE1) of the chicken alpha A-crystallin lens-specific enhancer
Matsuo, I.; Takeuchi, M.; Yasuda, K.
Biochemical and Biophysical Research Communications 184(1): 24-30
ISSN/ISBN: 0006-291X PMID: 1567432 DOI: 10.1016/0006-291x(92)91152-g
A lens-specific enhancer, an 84bp element between base pairs -162 and -79, of the chicken alpha A-crystallin gene is composed of two motifs, alpha CE1 (-162 and -134) and alpha CE2 (-119 and -99). Previous studies showed that a nuclear factor which binds to alpha CE1, termed alpha CEF1, is present at high levels in lens cells. Methylation interference analysis identified an inverted repeat of 5bp separated by 4bp, 5'-CTGGTTCCCACCAG-3', between positions -153 and -140 as an alpha CEF1-binding site. Gel mobility shift assays using synthetic oligonucleotides with site-directed mutations revealed that the alpha CEF1-binding consensus sequence is 5'-C(T/A)GGN6CC(A/T)G-3'. Comparison of this binding motif with regulatory sequences of diverse crystallin genes from diverse species suggests that alpha CE1 may be a ubiquitous crystallin gene enhancer.