Rab32 family proteins regulate autophagosomal components recycling.

In autophagy, autophagosomes deliver the lumenal contents to lysosomes for degradation via autophagosome-lysosome fusion. In contrast, autophagosome outer membrane components were recycled via autophagosomal components recycling (ACR), which is mediated by the recycler complex. The recycler complex, composed of SNX4, SNX5, and SNX17, cooperate with the dynein-dynactin complex to mediate ACR.

ULK phosphorylation of STX17 controls autophagosome maturation via FLNA.

Autophagy is a conserved and tightly regulated intracellular quality control pathway. ULK is a key kinase in autophagy initiation, but whether ULK kinase activity also participates in the late stages of autophagy remains unknown. Here, we found that the autophagosomal SNARE protein, STX17, is phosphorylated by ULK at residue S289, beyond which it localizes specifically to autophagosomes.

Autophagosomal components recycling on autolysosomes.

Autophagy is a multistage, intracellular process. Here, we highlight a recently identified autophagosomal components recycling (ACR) stage and the recycler complex (SNX4-SNX5-SNX17), which mediates recycling of autophagosomal outer membrane proteins on the autolysosome surface immediately following autophagosome-lysosome fusion. This discovery opens numerous research directions into the postfusion fate of autophagosomes.

The fate of autophagosomal membrane components.

During macroautophagy/autophagy, autophagosomes fuse with lysosomes to form autolysosomes. After fusion, the autophagosome inner membrane and enclosed substrates are degraded and transported out of lysosomes for recycling. The lysosomal membrane components are recycled by autophagic lysosome reformation (ALR) to generate new lysosomes.

Recycling of autophagosomal components from autolysosomes by the recycler complex.

Autolysosomes contain components from autophagosomes and lysosomes. The contents inside the autolysosomal lumen are degraded during autophagy, while the fate of autophagosomal components on the autolysosomal membrane remains unknown. Here we report that the autophagosomal membrane components are not degraded, but recycled from autolysosomes through a process coined in this study as autophagosomal components recycling (ACR).

[Inhibitory effect of BEZ235 on human prostate carcinoma in vitro].

To determine effects of BEZ235, an inhibitor of phosphoionsitol-3-kinase (PI3K)/mTOR, on the cell proliferation and migration in human prostate carcinoma lines including RWPE-1, PC3, and DU145 cells.
 Methods: Viability of RWPE-1, PC3, and DU145 cells was detected by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, while cell migration was analyzed by wound healing assay. Western blot and immunofluorescence were used to examine the changes of relevant protein expression.