TY - JOUR
T1 - Distal Sox Binding Elements of the αB-Crystallin Gene Show Lens Enhancer Activity in Transgenic Mouse Embryos
AU - Ijichi, Nobuhiro
AU - Tsujimoto, Naomi
AU - Iwaki, Toru
AU - Fukumaki, Yasuyuki
AU - Iwaki, Akiko
N1 - Funding Information:
We thank Drs. H. Kondoh and Y. Kamachi (Osaka University) for the gifts of the antisera for Sox1 and Sox2, and Dr. Hiroy-uki Sasaki (National Institute of Genetics) for the helpful discussions. We are also grateful to Ms. R. Funatsu for maintaining the mouse colonies and Ms. K. Hatanaka for the histological preparation. This work was supported by a Grant-in-Aid for General Scientific Research from the Ministry of Education, Science, Sports and Culture of Japan to AI (10680654). Data deposition: GenBank under accession number AF126248.
PY - 2004/3
Y1 - 2004/3
N2 - αB-Crystallin, a member of the small heat shock protein (sHSP) family, is expressed in various tissues including lens, heart, and skeletal muscle. Previously we identified the gene of HSPB2, another member of the sHSP family, located 1-kb upstream of the αB-crystallin gene in a head-to-head manner. In the present study, we found a highly conserved region of 220 bp approximately 2.4-kb upstream of the αB-crystallin gene and examined its role in expression of the αB-crystallin gene. Transgenic mice containing 3 kb of the upstream sequence of the αB-crystallin gene showed lacZ reporter gene expression in the lens as well as the myotome and heart on embryonic day 12.5. Deletion analysis revealed that the -2656/-2267 region including the conserved region with four putative Sox binding elements (E1-E4) exhibits lens enhancer activity toward the αB-crystallin promoter. Gel shift assays showed that the Sox1 and Sox2 proteins preferentially bound to E2 and E4. Moreover, disruption of E2 and E4 abolished the reporter gene expression in the lens. These results indicate that the newly identified enhancer with Sox elements activates the αB-crystallin promoter in the lens, although they are separated by the entire HSPB2 gene.
AB - αB-Crystallin, a member of the small heat shock protein (sHSP) family, is expressed in various tissues including lens, heart, and skeletal muscle. Previously we identified the gene of HSPB2, another member of the sHSP family, located 1-kb upstream of the αB-crystallin gene in a head-to-head manner. In the present study, we found a highly conserved region of 220 bp approximately 2.4-kb upstream of the αB-crystallin gene and examined its role in expression of the αB-crystallin gene. Transgenic mice containing 3 kb of the upstream sequence of the αB-crystallin gene showed lacZ reporter gene expression in the lens as well as the myotome and heart on embryonic day 12.5. Deletion analysis revealed that the -2656/-2267 region including the conserved region with four putative Sox binding elements (E1-E4) exhibits lens enhancer activity toward the αB-crystallin promoter. Gel shift assays showed that the Sox1 and Sox2 proteins preferentially bound to E2 and E4. Moreover, disruption of E2 and E4 abolished the reporter gene expression in the lens. These results indicate that the newly identified enhancer with Sox elements activates the αB-crystallin promoter in the lens, although they are separated by the entire HSPB2 gene.
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U2 - 10.1093/jb/mvh049
DO - 10.1093/jb/mvh049
M3 - Article
C2 - 15113840
AN - SCOPUS:1942424123
SN - 0021-924X
VL - 135
SP - 413
EP - 420
JO - Journal of biochemistry
JF - Journal of biochemistry
IS - 3
ER -