TEX264 is a major receptor for mammalian reticulophagy.

ABSTRACT

The endoplasmic reticulum (ER) is the main site of cellular protein and calcium homeostasis, as well as lipid synthesis in eukaryotic cells. Reticulophagy is the selective clearance and degradation of ER components and membranes by the cellular autophagy machinery. Recently, 2 groups (the laboratories of Noboru Mizushima and Wade Harper) independently identified the previously uncharacterized protein TEX264 (testis expressed gene 264) as a major receptor for selective reticulophagy in mammalian cells. Here we highlight and integrate the major findings of their recent work. Abbreviations AIM: Atg8-interacting motif; AP-MS affinity purification-mass spectrometry; ATL3 atlastin GTPase 3; Baf A1 bafilomycin A1; CCPG1 cell cycle progression 1; CRISPR clustered regularly interspaced short palindromic repeats; GABARAP gamma-aminobutyric acid receptor associated protein; GFP green fluorescent protein; GyrI gyrase inhibitor; IDR intrinsically disordered region; IP immunoprecipitation; KO knockout; LIR LC3-interacting region; MAP1LC3/LC3 microtubule-associated protein 1 light chain 3; MEF mouse embryonic fibroblast; MS mass spectrometry; MTOR mechanistic target of rapamycin kinase; RB1CC1/FIP200 RB1-inducible coiled-coil 1; RFP red fluorescent protein; RNAi RNA interference; RTN3 reticulon 3; RTN3L long isoform of RTN3; siRNA small interfering RNA; SARS selective autophagy receptors; ss signal sequence; TEM transmission electron microscopy, TEX264 testis expressed gene 264; TMT tandem mass tagging.