A novel nucleocytoplasmic traffic GTPase identified as a functional target of the bipartite geminivirus nuclear shuttle protein
| Autor: | Mariana R. Fontenelle, Elizabeth P. B. Fontes, Anésia A. Santos, Lilian H. Florentino, Claudine M. Carvalho, Francisco Murilo Zerbini |
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| Rok vydání: | 2008 |
| Předmět: |
Viral protein
Active Transport Cell Nucleus Arabidopsis Plant Science GTPase Biology medicine.disease_cause GTP Phosphohydrolases Two-Hybrid System Techniques Tobacco Genetics medicine Nuclear protein Movement protein Nuclear export signal Plant Diseases Cell Nucleus Microscopy Confocal Sequence Homology Amino Acid Arabidopsis Proteins Reverse Transcriptase Polymerase Chain Reaction Protoplasts Nuclear Proteins Cell Biology Plants Genetically Modified Cell biology Plant Leaves Plant Viral Movement Proteins Cell nucleus medicine.anatomical_structure Biochemistry RNA Plant Nucleocytoplasmic Transport Begomovirus DNA Viral Nuclear transport Sequence Alignment Plasmids |
| Zdroj: | The Plant Journal. 55:869-880 |
| ISSN: | 1365-313X 0960-7412 |
| Popis: | Summary In contrast to the accumulated data on nuclear transport mechanisms of macromolecules, little is known concerning the regulated release of nuclear-exported complexes and their subsequent trans-cytoplasmic movement. The bipartite begomovirus nuclear shuttle protein (NSP) facilitates the nuclear export of viral DNA and cooperates with the movement protein (MP) to transport viral DNA across the plant cell wall. Here, we identified a cellular NSP-interacting GTPase (NIG) with biochemical properties consistent with a nucleocytoplasmic transport role. We show that NIG is a cytosolic GTP-binding protein that accumulates around the nuclear envelope and possesses intrinsic GTPase activity. NIG interacts with NSP in vitro and in vivo (under transient expression), and redirects the viral protein from the nucleus to the cytoplasm. We propose that NIG acts as a positive contributor to geminivirus infection by modulating NSP nucleocytoplasmic shuttling and hence facilitating MP–NSP interaction in the cortical cytoplasm. In support of this, overexpression of NIG in Arabidopsis enhances susceptibility to geminivirus infection. In addition to highlighting the relevance of NIG as a cellular co-factor for NSP function, our findings also have implications for general nucleocytoplasmic trafficking of cellular macromolecules. |
| Databáze: | OpenAIRE |
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