Rab35 GTPase recruits NDP52 to autophagy targets

Abstract

Autophagy targets intracellular molecules, damaged organelles, and invading pathogens for degradation in lysosomes. Recent studies have identified autophagy receptors that facilitate this process by binding to ubiquitinated targets, including NDP52. Here, we demonstrate that the small guanosine triphosphatase Rab35 directs NDP52 to the corresponding targets of multiple forms of autophagy. The active GTP-bound form of Rab35 accumulates on bacteria-containing endosomes, and Rab35 directly binds and recruits NDP52 to internalized bacteria. Additionally, Rab35 promotes interaction of NDP52 with ubiquitin. This process is inhibited by TBC1D10A, a GAP that inactivates Rab35, but stimulated by autophagic activation via TBK1 kinase, which associates with NDP52. Rab35, TBC1D10A, and TBK1 regulate NDP52 recruitment to damaged mitochondria and to autophagosomes to promote mitophagy and maturation of autophagosomes, respectively. We propose that Rab35-GTP is a critical regulator of autophagy through recruiting autophagy receptor NDP52.

Molecular mechanisms of Streptococcus pneumoniae ‐targeted autophagy via pneumolysin, Golgi‐resident Rab41, and Nedd4‐1‐mediated K63‐linked ubiquitination

“…In our hand, LAMP‐1 recruitment to PCV was not affected in Rab41 KO MEFs (Figure S5c). Moreover, previous studies show colocalization of Rab7, 9A, 17, 23, 30, and 35 with GAS‐containing autophagic vesicles (GcAVs), and these Rabs are involved in GcAVs formation, GcAV‐GcAV membrane fusion, and GcAVs maturation (Minowa‐Nozawa, Nozawa, Okamoto‐Furuta, Kohda, & Nakagawa, ; Nozawa et al, ; Yamaguchi et al, ). In our hands, Rab17, 23, 30, and 35 were not recruited to PcAV, indicating differing intracellular fates and autophagic responses of pyogenic‐grouped GAS and mitis‐grouped S .…”

LAMTOR2/LAMTOR1 complex is required for TAX1BP1‐mediated xenophagy

“…On the other hand, galectin 8 has been shown to be essential to NDP52 recruitment during Salmonella infection (Thurston et al, ). Because we recently reported that NDP52 recruitment to intracellular GAS is mediated by ubiquitin and Rab35 but not galectin 8 (Minowa‐Nozawa et al, ), the NDP52 recruitment mechanism into invading bacteria differs between bacterial species. In this study, we showed that LAMTOR2 is involved in TAX1BP1 recruitment both to GAS and Salmonella .…”

“…The receptors NDP52 and TAX1BP1/CALCOCO3 have been reported to perform both of these functions during Salmonella infection (Tumbarello et al, 2015). We recently reported that the endosome-resident Rab GTPase Rab35 specifically recruits NDP52 to autophagy targets and autophagosomes (Minowa-Nozawa, Nozawa, Okamoto-Furuta, Kohda, & Nakagawa, 2017), but how other autophagy receptors are spatially regulated to target invading pathogens remains poorly understood.…”

NDP 52 interacts with mitochondrial RNA poly(A) polymerase to promote mitophagy

“…These results indicate that PHB2 and NDP52-MTPAP contribute distinct mitochondrial recognition mechanisms of mitophagy. A small GTPase, Rab35, recruits NDP52 to damaged mitochondria [40]. KD of Rab35 significantly reduced mitophagic flux after valinomycin treatment for 3 h (Fig EV4D), while cells with double KD of NDP52 and Rab35 showed a comparable level of mitophagic flux to cells treated with siRab35 or siNDP52 alone.…”

“…These results indicate that the interaction between NDP52 and MTPAP is not regulated by Rab35 and TBK1. Rab35 and TBK1 are involved in regulating the interaction between NDP52 and ubiquitin [40]; therefore, we presumed that the NDP52-MTPAP interaction and irruption of NDP52 into mitochondria are part of a ubiquitin-independent mechanism. Accordingly, we showed that NDP52ΔLIM-L, a ubiquitin-binding-deficient mutant of NDP52, interacts with MTPAP ( Fig 2F).…”