Analyses of the terminal sequences of West Nile virus structural proteins and of the in vitro translation of these proteins allow the proposal of a complete scheme of the proteolytic cleavages involved in their synthesis
| Autor: | Thomas Nowak, Petra M. Färber, Gisela Wengler, Gerd Wengler |
|---|---|
| Rok vydání: | 1989 |
| Předmět: |
viruses
Proteolysis medicine.medical_treatment Molecular Sequence Data Peptide Biology In Vitro Techniques Cleavage (embryo) Endoplasmic Reticulum Peptide Mapping chemistry.chemical_compound Viral Proteins Biosynthesis Virology medicine Amino Acid Sequence Peptide sequence chemistry.chemical_classification Viral Structural Proteins Messenger RNA Protease medicine.diagnostic_test Cell-Free System Hydrolysis NS2-3 protease Molecular Weight chemistry Biochemistry Protein Biosynthesis Protein Processing Post-Translational West Nile virus |
| Zdroj: | Virology. 169(2) |
| ISSN: | 0042-6822 |
| Popis: | The proteolytic processes involved in the synthesis of the structural proteins of the West Nile (WN) flavivirus were analyzed: The carboxy-terminal sequences of the structural proteins were determined and the proteins translated in vitro in the presence of membranes from a mRNA coding for the structural polyprotein were analyzed. The results obtained indicate that the following proteolytic activities are involved in the synthesis and assembly of WN virus structural proteins: The growing peptide chain which contains the sequences of the structural proteins in the order C-pre-M-E is cleaved at three places by cellular signalase(s). This cleavage generates the primary amino acid sequence of the mature structural proteins pre-M and E (and the amino-terminus of the ensuing nonstructural protein NS 1). The amino-terminal part of the polyprotein containing the amino acid residues 1 to 123 is released as a molecule which migrates slightly slower than the mature viral core protein and which presumably is associated to the RER membranes via its carboxy-terminal sequence. This protein is called the anchored C protein. Priorto or during assembly of intracellular virus particles the anchored C protein is converted into mature C protein by removal of the carboxy-terminal hydrophobic segment containing the amino acid residues 106 to 123. Presumably a virus-coded protease which can cleave the polyprotein after two basic amino acid residues is responsible for this cleavage. The cell-associated WN virus particles are constructed from the proteins C, pre-M, and E which contain the amino residues 1–105, 124–290, and 291–787 of the polyprotein, respectively. Cleavage of the pre-M protein between amino acid residues 215 and 216, presumably by a cellular enzyme located in the Golgi vesicles, and loss of the amino-terminal fragment of this protein are associated with the release of virus from the cells. |
| Databáze: | OpenAIRE |
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