Identification of a short amino acid sequence essential for efficient nuclear targeting of the Kaposi's sarcoma-associated herpesvirus/human herpesvirus-8 K8 protein.
The K8 protein of Kaposi's sarcoma-associated herpesvirus (KSHV)/human herpesvirus-8 is a member of the bZIP family of transcription factors, which has homology with the Epstein-Barr virus transcription and replication factor, EB1. In this report, we have analysed the subcellular localization of the K8 protein and characterized a 12 amino acid sequence rich in basic residues which is responsible for targeting the protein to the cell nucleus. Furthermore, we show that a K8 mutant lacking the nuclear localization sequence can be directed to the nucleus by co-expression with an intact K8 protein, suggesting that K8 homodimerizes in the cytoplasm of the cell in vivo.
Portes-Sentis
Stéphanie
S
Laboratoire de virologie humaine, U412 INSERM, ENS-Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France1.
Manet
Evelyne
E
Laboratoire de virologie humaine, U412 INSERM, ENS-Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France1.
Gourru
Géraldine
G
Laboratoire de virologie humaine, U412 INSERM, ENS-Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France1.
Sergeant
Alain
A
Laboratoire de virologie humaine, U412 INSERM, ENS-Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France1.
Gruffat
Henri
H
Laboratoire de virologie humaine, U412 INSERM, ENS-Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France1.
D000596:Amino Acids; D000818:Animals; D050976:Basic-Leucine Zipper Transcription Factors; D001665:Binding Sites; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism / Q000821:virology*; D006367:HeLa Cells; D019288:Herpesvirus 8, Human / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D016350:Leucine Zippers / Q000235:genetics; D016296:Mutagenesis; D019913:Nuclear Localization Signals / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D010446:Peptide Fragments; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins; D012514:Sarcoma, Kaposi / Q000821:virology; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*
D000596:Amino Acids; D050976:Basic-Leucine Zipper Transcription Factors; D002352:Carrier Proteins; C118265:K8 protein, Human herpesvirus 8; D019913:Nuclear Localization Signals; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D014764:Viral Proteins