Cell type dependent transcription regulation by chick homeodomain proteins.
Five chick homeodomain proteins (CHOXs), CHOX-1.7, -1.1, -1.4, -4.2 and -2.6, had different transcription-regulating activities in a chick cultured cell line, LMH. In particular, CHOX-1.7 highly activated transcription when NP6 was used as the target site whereas CHOX-1.4 did not. This was mainly due to differences in the activation domains since both proteins bound to NP with almost the same affinities in vitro. In LMH cells, they competitively acted on target gene transcription. Moreover, the strength of the CHOX-1.4 activation domain depended on the cell type. These findings suggest that the effect on a target gene is determined by a combination of CHOXs and cell types.
Department of Cell Biology, Tohoku University, Sendai, Japan.
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Sasaki
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Yamamoto
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Kuroiwa
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002645:Chickens / Q000235:genetics*; D004274:DNA, Recombinant / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D004331:Drosophila melanogaster / Q000235:genetics; D005786:Gene Expression Regulation; D005801:Genes, Homeobox; D051379:Mice / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic
D004274:DNA, Recombinant; D004268:DNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors