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Updated: Oct 1, 2026

Rapid Isolation of the Mitoribosome from HEK Cells
Published on: October 4, 2018
The nascent polypeptide-associated complex (NAC) promotes interaction of ribosomes with the mitochondrial surface in
Rebecca George1, Peter Walsh, Travis Beddoe
1Department of Biochemistry, La Trobe University, 3083, Bundoora, Australia.
Abstract:
The nascent polypeptide-associated complex (NAC) is a peripheral component of cytoplasmic ribosomes, and interacts with nascent chains as they leave the ribosome. Yeast mutants lacking NAC translate polypeptides normally, but have fewer ribosomes associated with the mitochondrial surface. The mutants lacking NAC suffer mitochondrial defects and have decreased levels of proteins like fumarase, normally targeted to mitochondria co-translationally. NAC might contribute to a ribosomal environment in which amino-terminal, mitochondrial targeting sequences can effectively adopt their appropriate conformation.
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