Disease relevance of AURAVgp1

• The Semliki Forest virus capsid protein contains a chymotrypsin-like protease domain that must fold before it can autocatalytically cleave the protein from a larger polyprotein precursor [1].
• Here we describe a new packaging system for Semliki Forest virus (SFV) based on a the use of a two-helper system in which the capsid and spike proteins of the C-p62-6K-E1 polyprotein are expressed from two independent RNA molecules [2].
• The polyprotein P1234 is produced when translational readthrough occurs or when the opal termination codon has been replaced by a sense codon in the alphavirus genome [3].
• The structural proteins are also translated as a polyprotein precursor which is cleaved to produce a nucleocapsid protein and two integral membrane glycoproteins as well as two small peptides not present in the mature virion [4].
• A high level of similarity was detected between the leader protease of foot-and-mouth-disease virus and the protease of murine hepatitis coronavirus which cleaves the N-terminal p28 protein from the polyprotein [5].

High impact information on AURAVgp1

• In addition, the capsid protein has an autoproteolytic activity whereby the C-terminal tryptophan is used as the substrate for cotranslational cleavage of the viral structure polyprotein [6].
• This construct has correct processing of the replicase polyprotein, produces viable virus and expresses detectable EGFP fluorescence upon infection of cultured cells and cells of the mouse brain [7].
• At the C terminus of the C protein is a stretch of 20 hydrophobic aa which also serves as the signal sequence for E2, indicating that the cleavage of C from the polyprotein precursor may be catalyzed by signalase in the lumen of the endoplasmic reticulum [8].
• Translation of the 26S mRNA began at the first AUG (positions 59 to 61) initiation codon and continued with an open reading frame that coded for a polyprotein of 1258 amino acids ending at a UAA ochre termination codon (positions 3776 to 3778) [9].
• The deduced amino acid sequence of the VEE polyprotein shows an overall homology of 44 to 46% with the precursor polyproteins of SIN, SF, and RR viruses [10].

Associations of AURAVgp1 with chemical compounds

• Negative strand synthesis is unstable because of the failure to form initial transcription complexes after host factors that are part of the replicase are depleted or the half-life of polyprotein precursors like P23 is shortened [11].

References