MSSP, a protein binding to an origin of replication in the c-myc gene, interacts with a catalytic subunit of DNA polymerase alpha and stimulates its polymerase activity.
MSSP has been identified as a protein that binds to both single- and double-stranded sequences of a putative DNA replication origin sequence in the human c-myc gene. MSSP possesses versatile functions, including stimulation of DNA replication, transcriptional regulation, apoptosis induction, and cell transformation coordinated by c-Myc. MSSP contains two RNP domains, RNP1-A and RNP1-B, both of which are necessary for all of the functions of MSSP. In this study, we found that MSSP binds to the N-terminal region of a catalytic subunit of a human DNA polymerase alpha via its RNP domains both in vitro and in human cells. Furthermore, MSSP was released from the putative DNA replication origin of the c-myc gene after it complexed with DNA polymerase alpha, and MSSP stimulated DNA polymerase activity in vitro.
Niki
T
T
Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo, Japan.
Galli
I
I
Ariga
H
H
Iguchi-Ariga
S M
SM
D002460:Cell Line; D004256:DNA Polymerase I / Q000235:genetics* / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004789:Enzyme Activation; D016259:Genes, myc; D006801:Humans; D011485:Protein Binding; D016601:RNA-Binding Proteins; D018741:Replication Origin
D004268:DNA-Binding Proteins; C086384:RBMS1 protein, human; D016601:RNA-Binding Proteins; D004256:DNA Polymerase I