TY - JOUR
T1 - Alleviation of historic H1-mediated transcriptional repression and chromatin compaction by the acidic activation region in chromosomal protein HMG-14
AU - Ding, Han Fei
AU - Bustin, Michael
AU - Hansen, Ulla
PY - 1997/10
Y1 - 1997/10
N2 - Histone H1 promotes the generation of a condensed, transcriptionally inactive, higher-order chromatin structure. Consequently, historic H1 activity must be antagonized in order to convert chromatin to a transcriptionally competent, more extended structure. Using simian virus 40 minichromosomes as a model system, we now demonstrate that the nonhistoric chromosomal protein HMG-14, which is known to preferentially associate with active chromatin, completely alleviates historic H1-mediated inhibition of transcription by RNA polymerase II. HMG-14 also partially disrupts histone H1-dependent compaction of chromatin. Both the transcriptional enhancement and chromatin-unfolding activities of HMG-14 are mediated through its acidic, C-terminal region. Strikingly, transcriptional and structural activities of HMG-14 are maintained upon replacement of the C-terminal fragment by acidic regions from either GAL4 or HMG-2. These data support the model that the acidic C terminus of HMG-14 is involved in unfolding higher-order chromatin structure to facilitate transcriptional activation of mammalian genes.
AB - Histone H1 promotes the generation of a condensed, transcriptionally inactive, higher-order chromatin structure. Consequently, historic H1 activity must be antagonized in order to convert chromatin to a transcriptionally competent, more extended structure. Using simian virus 40 minichromosomes as a model system, we now demonstrate that the nonhistoric chromosomal protein HMG-14, which is known to preferentially associate with active chromatin, completely alleviates historic H1-mediated inhibition of transcription by RNA polymerase II. HMG-14 also partially disrupts histone H1-dependent compaction of chromatin. Both the transcriptional enhancement and chromatin-unfolding activities of HMG-14 are mediated through its acidic, C-terminal region. Strikingly, transcriptional and structural activities of HMG-14 are maintained upon replacement of the C-terminal fragment by acidic regions from either GAL4 or HMG-2. These data support the model that the acidic C terminus of HMG-14 is involved in unfolding higher-order chromatin structure to facilitate transcriptional activation of mammalian genes.
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U2 - 10.1128/mcb.17.10.5843
DO - 10.1128/mcb.17.10.5843
M3 - Article
C2 - 9315642
AN - SCOPUS:0030610561
SN - 0270-7306
VL - 17
SP - 5843
EP - 5855
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
IS - 10
ER -