α-Tropomyosin with a D175N or E180G mutation in only one chain differs from tropomyosin with mutations in both chains.

ABSTRACT: α-Tropomyosin (Tm) carrying hypertrophic cardiomyopathy mutation D175N or E180G was expressed in Escherichia coli. We have assembled dimers of two polypeptide chains in vitro that carry one (αα*) or two (α*α*) copies of the mutation. We found that the presence of the mutation has little effect on dimer assembly, thereby predicting that individuals heterozygous for the Tm mutations are likely to express both αα* and α*α* Tm. Depending on the expression level, the heterodimer may be the predominant form in individuals carrying the mutation. Thus, it is important to define differences in the properties of Tm molecules carrying one or two copies of the mutation. We examined the Tm homo- and heterodimer properties: actin affinity, thermal stability, calcium regulation of myosin subfragment 1 bi

SUBMITTER: Janco M 

PROVIDER: S-EPMC3711130 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature