The Kaposi's sarcoma-associated herpesvirus K8 protein interacts with CREB-binding protein (CBP) and represses CBP-mediated transcription.
Kaposi's sarcoma-associated herpesvirus (KSHV) open reading frame K8 encodes a basic region-leucine zipper protein of 237 amino acids that homodimerizes with its bZIP domain. KSHV K8 shows significant homology to the Epstein-Barr virus (EBV) immediate-early protein Zta, a key regulator in the reactivation and replication of EBV. In this study, we report that K8, like its homolog EBV Zta, interacts with cellular CREB-binding protein (CBP) in vivo and in vitro. This interaction requires the C/H3 domain of CBP and the basic region of K8. K8 represses CBP-mediated transcription by competing with limited amounts of cellular CBP, exemplified by the reduced expression from the AP-1 and human immunodeficiency virus long terminal repeat promoters.
Hwang
S
S
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
Gwack
Y
Y
Byun
H
H
Lim
C
C
Choe
J
J
D050882:CREB-Binding Protein; D002460:Cell Line; D015967:Gene Expression Regulation, Viral; D019288:Herpesvirus 8, Human / Q000502:physiology*; D006801:Humans; D009687:Nuclear Proteins / Q000502:physiology*; D015534:Trans-Activators / Q000502:physiology*; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000502:physiology*; D014779:Virus Replication
D009687:Nuclear Proteins; D015534:Trans-Activators; D014764:Viral Proteins; D050882:CREB-Binding Protein; C494363:CREBBP protein, human