TY - JOUR
T1 - High mobility group protein 1 interacts specifically with the core domain of human TATA box-binding protein and interferes with transcription factor IIB within the pre-initiation complex
AU - Sutrias-Grau, Montserrat
AU - Bianchi, Marco E.
AU - Bernués, Jordi
PY - 1999/1/15
Y1 - 1999/1/15
N2 - The high mobility group (HMG) box domain has defined a family of proteins, mostly transcription factors, that specifically interacts with DNA on the minor groove and sharply bends it. The founding member of the family, HMG1, does not specifically recognize regular BDNA but is recruited to DNA by interaction with other transcription factors and TATA box-binding protein (TBP). However, conflicting effects of HMG1 on transcription have been reported. We show that the interaction between HMG1 and TBP is species- specific. This interaction in turn affects the interaction of TBP with transcription factor (TF) IIB and is competed by TFIIA. A primary binding site was mapped to the H2' α-helix in the highly conserved core domain of human TBP. On HMG1, the primary binding site was only in the HMG box A, and HMG box A was also sufficient to interact with native TFIID. Both HMG boxes efficiently repressed transcription in vitro as fusions to the Ga14-DNA binding domain. Additionally, HMG box B showed a weak level of activation at very low amounts. These results suggest a general involvement of HMG1 at the early stages of polymerase II transcription that may result in subtle activation or repression of individual genes.
AB - The high mobility group (HMG) box domain has defined a family of proteins, mostly transcription factors, that specifically interacts with DNA on the minor groove and sharply bends it. The founding member of the family, HMG1, does not specifically recognize regular BDNA but is recruited to DNA by interaction with other transcription factors and TATA box-binding protein (TBP). However, conflicting effects of HMG1 on transcription have been reported. We show that the interaction between HMG1 and TBP is species- specific. This interaction in turn affects the interaction of TBP with transcription factor (TF) IIB and is competed by TFIIA. A primary binding site was mapped to the H2' α-helix in the highly conserved core domain of human TBP. On HMG1, the primary binding site was only in the HMG box A, and HMG box A was also sufficient to interact with native TFIID. Both HMG boxes efficiently repressed transcription in vitro as fusions to the Ga14-DNA binding domain. Additionally, HMG box B showed a weak level of activation at very low amounts. These results suggest a general involvement of HMG1 at the early stages of polymerase II transcription that may result in subtle activation or repression of individual genes.
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U2 - 10.1074/jbc.274.3.1628
DO - 10.1074/jbc.274.3.1628
M3 - Article
C2 - 9880542
AN - SCOPUS:0033555550
VL - 274
SP - 1628
EP - 1634
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 3
ER -