The Mitochondrial Ribosome Associated Protein Quality Control System and Diseases / 中国生物化学与分子生物学报

ABSTRACT

Protein synthesis is a complex process. Under certain circumstances, abnormal ribosome stalling will occur during translation, resulting in the inability to effectively recover the ribosome for the next round of translation. Nascent polypeptides arisen from the stalled ribosome are at risk of forming aggregate species, and disturbing protein homeostasis and contributing to development of diseases. The ribosome-associated protein quality control(RQC) pathway provides a rescue method for recovering of stalled ribosomes and for proteasomal degradation of nascent polypeptides obstructed on 60S subunits. The latest researches show that there are RQC rescue pathways on the surface of mitochondria (called mitochondrial ribosome-associated protein quality control, mitoRQC). Mitochondria are important organelles involved in energy production and metabolism in eukaryotic cells. More than 98% of mitochondrial proteins are encoded by nuclear genes and transported from the cytoplasm to mitochondria. These proteins are potential targets for mitoRQC, which works synergistically with the internal regulation system of mitochondria to maintain mitochondrial stability. In this review, we will focus on the recent progress on the RQC and mitoRQC pathway as well as their implications in the progression of diseases.