RT Journal Article SR Electronic(1) A1 Mottet, Geneviève A1 Müller, Virginie A1 Roux, Laurent YR 1999 T1 Characterization of Sendai virus M protein mutants that can partially interfere with virus particle production JF Journal of General Virology, VO 80 IS 11 SP 2977 OP 2986 DO https://doi.org/10.1099/0022-1317-80-11-2977 PB Microbiology Society, SN 1465-2099, AB Substitution of Val113 in Sendai virus (SeV) M protein generates non-functional polypeptides, characterized by their exclusion from virus particles and by their ability to interfere with virus particle production. These phenotypic traits correlate with a single-band PAGE migration profile, in contrast to wild-type M (Mwt ), which separates into two species, one of which is a phosphorylated form. The single-band migration is likely to result from a conformational change, as evidenced by the lack of maturation of a native epitope and by a particular tryptic digestion profile, and not from the phosphorylation of all M molecules, an assumption consistent with the PAGE migration feature. One of the M mutants (HA–M30 , an M protein carrying Thr112Met and Val113 Glu substitutions tagged with an influenza virus haemagglutinin epitope) was characterized further in the context of SeV infection, i.e. under conditions of co-expression with Mwt. HA–M 30 is shown (i) to bind mainly to membrane fractions, (ii) not to co-precipitate Mwt, as HA–Mwt does, (iii) to interfere with the binding of nucleocapsids to membranes and (iv) to accumulate in perinuclear regions, in contrast to HA-Mwt , which is also found at the cell periphery. Such mutants constitute potential tools for the identification of critical steps in paramyxovirus assembly and budding., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-80-11-2977