Abstract
hRPB11 is a core subunit of RNA polymerase II (pol II) specifically down-regulated on doxorubicin (dox) treatment. Levels of this protein profoundly affect cell differentiation, cell proliferation, and tumorigenicity in vivo. Here we describe Che-1, a novel human protein that interacts with hRPB11. Che-1 possesses a domain of high homology with Escherichia coli RNA polymerase final sigma-factor 70 and SV40 large T antigen. In addition, we report that Che-1 interacts with the retinoblastoma susceptibility gene (Rb) by two distinct domains. Functionally, we demonstrate that Che-1 represses the growth suppression function of Rb, counteracting the inhibitory action of Rb on the trans-activation function of E2F1. These results identify a novel protein that binds Rb and the core of pol II, and suggest that Che-1 may be part of transcription regulatory complex.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Amino Acid Sequence
-
Carrier Proteins*
-
Cell Cycle / physiology
-
Cell Cycle Proteins*
-
Cell Division / physiology
-
Cell Line
-
Cloning, Molecular
-
DNA-Binding Proteins*
-
E2F Transcription Factors
-
E2F1 Transcription Factor
-
Humans
-
Molecular Sequence Data
-
Protein Binding
-
RNA Polymerase II / chemistry
-
RNA Polymerase II / metabolism*
-
Retinoblastoma Protein / antagonists & inhibitors
-
Retinoblastoma Protein / metabolism*
-
Retinoblastoma Protein / physiology
-
Retinoblastoma-Binding Protein 1
-
Sequence Homology, Amino Acid
-
Transcription Factor DP1
-
Transcription Factors / metabolism
Substances
-
Carrier Proteins
-
Cell Cycle Proteins
-
DNA-Binding Proteins
-
E2F Transcription Factors
-
E2F1 Transcription Factor
-
E2F1 protein, human
-
Retinoblastoma Protein
-
Retinoblastoma-Binding Protein 1
-
Transcription Factor DP1
-
Transcription Factors
-
RNA Polymerase II