The enterovirus 2B protein contains a putative amphipathic alpha-helix that includes three positively charged and one negatively charged residue. Previously, we observed that replacement of the @entity367 -40 residue with a @entity376 residue (mutation 2B-E[40]K) in the amphipathic alpha-helix of the coxsackie B3 virus 2B protein resulted in a quasi-infectious phenotype. On one occasion, however, transfection of 2B-E[40]K RNA transcripts gave rise to a virus stock in which the mutation was retained. This study was aimed at elucidating the molecular mechanism underlying this observation. Sequence analysis of the viral RNA provided no evidence for a second-site suppression mutation that rescued the defect of the 2B-E[40]K mutation in cis. Therefore, the possibility was considered that the defect caused by the 2B-E[40]K mutation was complemented in trans by viable revertants that had emerged in the virus population. The transfection-derived virus stock indeed contained a small fraction of (pseudo)revertant viruses, carrying the original @entity367 -40, @entity1889 -40 or @entity2734 -40, rather than the introduced @entity376 -40. Consistent with the idea that the 2B-E[40] @entity60418 is unable to grow without the aid of trans-acting wild-type(-like) proteins, only the (pseudo)revertant viruses were able to produce individual plaques. Further support for the idea of trans-rescue was obtained using a genetic complementation assay, which revealed the occurrence of a low level of trans-complementation of the 2B-E[40]K mutation by wild-type virus. This is the first report that provides evidence that a @entity74 in the enterovirus 2B protein can be complemented in trans.

Trans-complementation of a XXXX in the coxsackie B3 virus 2B protein.

@entity2734 :: ('CHEBI:17196', 'Chemical') :: ['asparagine'] @entity60418 :: ('260684', 'Species') :: ['K virus'] @entity376 :: ('CHEBI:25094', 'Chemical') :: ['lysine'] @entity74 :: ('MESH:D030342', 'Disease') :: ['genetic defect'] @entity367 :: ('CHEBI:18237', 'Chemical') :: ['glutamic acid'] @entity1889 :: ('CHEBI:26986', 'Chemical') :: ['threonine']
@entity74 :: (MESH:D030342,Disease) :: ['genetic defect']
