DENN domain-containing protein 3 (DENND3)

Guanine nucleotide exchange factor (GEF) activating RAB12. Promotes the exchange of GDP to GTP, converting inactive GDP-bound RAB12 to its active GTP-bound form (PubMed:20937701).

Regulates autophagy in response to starvation through RAB12 activation. Starvation contributes to ULK1/2-dependent phosphorylation of Ser-472 and Ser-490, which in turn allows recruitment of 14-3-3 adapter proteins and contributes to up-regulation of GEF activity towards RAB12 (By similarity).