Related Experiment Videos
Biochemical mapping of the foot-and-mouth disease virus genome
Abstract:
Four primary cleavage products, mol. wt. 10(3) X 100, 88, 56 and 52 (P100, P85, P56 and P52 respectively) are present in BHK 2I cells infected with foot-and-mouth disease virus (FMDV). However, no precursor polyprotein equal to the sum of their mol. wt. was detected, even when amino acid analogues and proteolytic enzyme inhibitors were used. Three of the primary products were shown to cleave to smaller polypeptides, including the capsid polypeptides of the virus. Polypeptide P88, which was shown to be the precursor of the capsid polypeptides, is translated from the gene located at the 5'-end of the genome. The order of the structural polypeptides, determined by the use of emetine, is VP4, VP2, VP3, VP1. The order of the remaining primary cleavage products is P52, P56 and P100. P56 is a stable product, identical with the virus infection associated (VIA) antigen found in virus harvests. The function of the other two products P52 and P100 is not known. EMDV thus differs from other picornaviruses in that there is an extra primary cleavage product, apparently resulting from translation of more of the virus genome.
Insights
Foot-and-mouth disease virus (FMDV) infection in cells yields four main cleavage products, with P88 identified as the precursor to viral capsid proteins. FMDV processing differs from other picornaviruses due to an additional primary cleavage product.
Area of Science:
- Molecular virology
- Protein biochemistry
- Cellular biology
Background:
- Foot-and-mouth disease virus (FMDV) is a significant pathogen in livestock.
- Understanding viral protein processing is crucial for developing antiviral strategies.
- Picornavirus replication involves complex polyprotein cleavage events.
Purpose of the Study:
- To elucidate the primary cleavage products of FMDV in infected cells.
- To determine the precursor-product relationships and polypeptide order.
- To compare FMDV processing with that of other picornaviruses.
Main Methods:
- Infection of BHK 21 cells with FMDV.
- Analysis of viral protein cleavage products using molecular weight determination.
- Investigation using amino acid analogues and proteolytic enzyme inhibitors.
- Determination of polypeptide order using emetine treatment.
Main Results:
- Four primary cleavage products (P100, P88, P56, P52) were identified in FMDV-infected BHK 21 cells.
- No intact precursor polyprotein was detected, even under inhibitory conditions.
- P88 was confirmed as the precursor to viral capsid polypeptides (VP4, VP2, VP3, VP1).
- P56 was identified as the stable virus infection associated (VIA) antigen.
Conclusions:
- FMDV exhibits a unique polyprotein processing pathway compared to other picornaviruses.
- The presence of an additional primary cleavage product suggests translation of a larger portion of the FMDV genome.
- The functions of P100 and P52 remain undetermined, warranting further investigation.