High-mobility group protein 2 may be involved in the locus control region regulation of the beta-globin gene cluster.
Expression regulation of the beta-globin gene cluster is a result of synergistic interactions between cis-elements and trans-acting factors. Previous studies usually concentrated on the core sequence of each hypersensitive site in the locus control region of the beta-globin gene cluster. But more and more evidence illustrates that the flanking regions are indispensable also. Using electrophoretic mobility shift assay and solid-phase DNase I footprinting methods, we identified a small nuclear protein from K562 cells that binds specifically to the first AT-rich region flanking the hypersensitive site 2 core sequence of the human beta-globin gene locus control region. N-terminal sequencing of the enriched protein proved that it is a member of the high-mobility group protein 2 family. This indicates that the AT-rich region in human hypersensitive site 2 may take part in the regulation of the beta-globin gene cluster by facilitating DNA bending, which is a prerequisite for the looping mechanism in this region.
Lv
Xiang
X
National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, People's Republic of China.
Xu
Dong-dong
DD
Liu
De-Pei
DP
Li
Lei
L
Hao
De-long
DL
Liang
Chih-chuan
CC
D001483:Base Sequence; D018983:DNA Footprinting; D005786:Gene Expression Regulation; D005914:Globins / Q000235:genetics*; D024261:HMGB2 Protein / Q000378:metabolism*; D006801:Humans; D020014:K562 Cells; D019901:Locus Control Region / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D020218:Response Elements / Q000235:genetics
D024261:HMGB2 Protein; D005914:Globins