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Human pentatricopeptide proteins: only a few and what do they do?
Robert N Lightowlers1, Zofia M A Chrzanowska-Lightowlers2
1The Wellcome Trust Centre for Mitochondrial Research; Institute for Cell and Molecular Biosciences; Newcastle University; The Medical School; Framlington Place; Newcastle upon Tyne, UK.
Abstract:
Pentatricopeptide repeat (PPR) proteins constitute a large family of RNA-binding proteins that contain a canonical 35 residue repeat motif. Originally identified in Arabidopsis thaliana, family members are found in protists, fungi, and metazoan but are by far most abundant in plant organelles. Seven examples have been identified in human mitochondria and roles have been tentatively ascribed to each. In this review, we briefly outline each of these PPR proteins and discuss the role each is believed to play in facilitating mitochondrial gene expression.
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