Role of the N- and C-terminal extensions on the activity of mammalian mitochondrial translational initiation factor 3.

ABSTRACT: Mammalian mitochondrial translational initiation factor 3 (IF3(mt)) promotes initiation complex formation on mitochondrial 55S ribosomes in the presence of IF2(mt), fMet-tRNA and poly(A,U,G). The mature form of IF3(mt) is predicted to be 247 residues. Alignment of IF3(mt) with bacterial IF3 indicates that it has a central region with 20-30% identity to the bacterial factors. Both the N- and C-termini of IF3(mt) have extensions of approximately 30 residues compared with bacterial IF3. To examine the role of the extensions on IF3(mt), deletion constructs were prepared in which the N-terminal extension, the C-terminal extension or both extensions were deleted. These truncated derivatives were slightly more active in promoting initiation complex formation than the mature form of IF3(mt). Mitoc

SUBMITTER: Bhargava K 

PROVIDER: S-EPMC1310894 | biostudies-literature | 2005

REPOSITORIES: biostudies-literature