Advances in the study of mitophagy-related receptor proteins / 生理学报

Cells selectively scavenge redundant or damaged mitochondria by mitophagy, which is an important mechanism of mitochondrial quality control. Recent studies have shown that mitophagy is mainly regulated by autophagy-related genes (Atgs) in yeast cells, while mitochondrial membrane associated proteins such as PTEN-induced putative kinase 1 (PINK1), NIX/BNIP3L, BNIP3, FUN14 domain containing 1 (FUNDC1), FKBP8/FKBP38, Bcl-2-like protein 13 (Bcl2L13), nucleotide binding domain and leucine-rich-repeat-containing proteins X1 (NLRX1), prohibitin 2 (PHB2) and lipids such as cardiolipin (CL) are the key mitophagic receptors in mammalian cells, which can selectively recognize damaged mitochondria, recruit them into isolation membranes by binding to microtubule-associated protein 1 light chain 3 (LC3) or γ-aminobutyric acid receptor-associated protein (GABARAP), and then fuse with lysosomes to eliminate the trapped mitochondria. This article reviews recent research progress of mitophagy-related receptor proteins.

The role and mechanism of leucyl-tRNA synthetase in the regulation of protein synthesis in aging skeletal muscle / 生理学报

The imbalance of protein metabolism is the major cause of skeletal muscle atrophy, and the decrease of protein synthesis directly leads to the occurrence and development of age-related sarcopenia. The canonical role of leucyl-tRNA synthetase (LeuRS) is ligating leucine to the cognate tRNA, and thus it plays a central role in genetic coding. With the further studies of LeuRS in recent years, LeuRS has been found to control protein homeostasis in aging skeletal muscle via its non-canonical role. In this paper, we reviewed the structure and biological features of aminoacyl-tRNA synthetase and LeuRS, and summarized the recent advances in studies on the effects of LeuRS in regulating aging skeletal muscle protein synthesis as an intracellular leucine sensor. Moreover, we also analyzed the potential role of LeuRS in activation of mammalian target of rapamycin complex 1 (mTORC1) signaling transduction pathway in response to anabolic stimuli such as exercise and amino acids ingestion. This paper may provide some new ideas for the prevention, diagnosis and treatment of age-related sarcopenia.