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A homeodomain protein binds to gamma-globin gene regulatory sequences.

ABSTRACT: Developmental regulation of gamma-globin gene expression probably occurs through developmental-stage-specific trans-acting factors able to promote the interaction of enhancer elements located in the far upstream locus control region with regulatory elements in the gamma gene promoters and 3' A gamma enhancer located in close proximity to the genes. We have detected a nuclear protein in K562 and baboon fetal bone marrow nuclear extracts capable of binding to A+T-rich sequences in the locus control region, gamma gene promoter, and 3' A gamma enhancer. SDS/polyacrylamide gel analysis of the purified K562 binding activity revealed a single protein of 87 kDa. A K562 cDNA clone was isolated encoding a beta-galactosidase fusion protein with a DNA binding specificity identical to that of the K562/fetal bone marrow nuclear protein. The cDNA clone encodes a homeodomain homologous to the Drosophila antennapedia protein.

SUBMITTER: Lavelle D

PROVIDER: S-EPMC52286 | biostudies-other | 1991 Aug

REPOSITORIES: biostudies-other

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A homeodomain protein binds to gamma-globin gene regulatory sequences.

Lavelle D D Ducksworth J J Eves E E Gomes G G Keller M M Heller P P DeSimone J J

Proceedings of the National Academy of Sciences of the United States of America 19910801 16

Developmental regulation of gamma-globin gene expression probably occurs through developmental-stage-specific trans-acting factors able to promote the interaction of enhancer elements located in the far upstream locus control region with regulatory elements in the gamma gene promoters and 3' A gamma enhancer located in close proximity to the genes. We have detected a nuclear protein in K562 and baboon fetal bone marrow nuclear extracts capable of binding to A+T-rich sequences in the locus contro ...[more]

PMID: 1871139

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