Kaposi's sarcoma-associated herpesvirus K8 protein interacts with hSNF5.
Kaposi's sarcoma-associated herpesvirus (KSHV) is a human gammaherpesvirus related to Epstein-Barr virus (EBV) and herpesvirus saimiri. KSHV open reading frame K8 encodes a basic region-leucine zipper protein of 237 aa that homodimerizes. K8 shows significant similarity to the EBV immediate-early protein Zta, a key regulator of EBV reactivation and replication. In this study, a carboxyl-terminal deletion mutant of K8, K8(1-115), that had strong transactivating properties was found. Screening using transcriptionally inactive K8(1-75) showed that K8 interacts and co-localizes with hSNF5, a cellular chromatin-remodelling factor, both in vivo and in vitro. This interaction requires aa 48-183 of hSNF5 and 1-75 of K8. In a yeast expression system, the ability of K8 and K8(1-115) to activate transcription requires the presence of SNF5, the yeast homologue of hSNF5. These data suggest a mechanism by which the SWI-SNF complex is recruited to specific genes. They also suggest that K8 functions as a transcriptional activator under specific conditions and that its transactivation activity requires its interaction with the cellular chromatin remodelling factor hSNF5.
Hwang
Seungmin
S
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
Lee
Daeyoup
D
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
Gwack
Yousang
Y
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
Min
Hyesun
H
Department of Food and Nutrition, Hannam University, Daejeon 306-791, Korea.
Choe
Joonho
J
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
D050976:Basic-Leucine Zipper Transcription Factors; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D017353:Gene Deletion; D015967:Gene Expression Regulation, Viral; D019288:Herpesvirus 8, Human / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D016350:Leucine Zippers; D011485:Protein Binding; D012097:Repressor Proteins; D000071796:SMARCB1 Protein; D015534:Trans-Activators; D014157:Transcription Factors; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014775:Virus Activation; D014779:Virus Replication
D050976:Basic-Leucine Zipper Transcription Factors; D002352:Carrier Proteins; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; C118265:K8 protein, Human herpesvirus 8; D012097:Repressor Proteins; D000071796:SMARCB1 Protein; C513266:SMARCB1 protein, human; D015534:Trans-Activators; D014157:Transcription Factors; D014764:Viral Proteins