Autophagy Research Update: What a difference a year makes!

Animal Models to Study Autophagy

Best Methods to Induce and Inhibit Autophagy Pharmacologically

E-syt in Autophagosome biogenesis: What is the source of it all?

Lysosomal Dysfunction is Linked to Exosomal Secretion

UVRAG - A regulator of membrane trafficking in autophagy and endocytosis

UV resistance-associated gene (UVRAG) is a tumor suppressor that is commonly mutated in colon and breast cancer. While UVRAG was discovered for its ability to complement UV sensitivity in xeroderma pigmentosum cells, its main functions are in autophagy, endocytosis, and apoptosis. During autophagy UVRAG interacts with Beclin 1 to promote autophagosome formation. UVRAG can also interact with VPS16 to recruit membrane fusion machinery to mediate autophagosome maturation.

VPS34 - autophagy initiator and regulator of endosomal trafficking

VPS34, vacuolar protein sorting 34, is the only identified Class III phosphoinositide-3 kinase (PI3K) in mammals and is ubiquitously expressed in all eukaryotic cells. VPS34 is a 100 kDa protein responsible for phosphorylating phosphatidylinositol to produce phosphatidylinositol 3-phosphate (PI3P). PI3P is an important intermediate in the development of the double-membraned autophagosome during autophagy, indicating a role for VPS34 in autophagy initiation. PI3P allows VPS34 to form complexes with ATG14L during the elongation of the autophagosome membrane.

ULK1 - mammalian homologue of the yeast ATG1 kinase

Autophagy is an important cellular process involved in degradation and recycling of cellular macromolecules in response to stress or starvation. Autophagy is carried out in four main phases: phagophore nucleation, autophagosome elongation, docking and fusion with a lysosome, and vesicle breakdown and degradation. ULK1, also known as UNC51-like autophagy activating kinase 1, is a 112 kDa protein with serine-threonine kinase activity. ULK1 is one of two mammalian homologues of the yeast ATG1 kinase, known for its role in autophagy initiation (1).

VPS41 - An important regulator of lysosomal trafficking

Membrane fusion is an essential step during the trafficking of endosomes and vesicles throughout the cell. Membrane fusion events are facilitated by multisubunit tethering complexes (MTC) including CORVET and HOPS. These complexes interact with Rab GTPases and SNARE proteins to promote the fusion of endosomes and lysosomes (1). In yeast VPS41 is a component of the HOPS complex that is needed for transport of endosomes and Golgi-derived vesicles to the vacuole. The choice between these two substrates is facilitated by the phosphorylation of VPS1 by Yck3 (2). Carbrera et al.

Beclin 2, a mammal-specific homolog of Beclin 1 with unique functional similarities and differences

Beclin 2 (BECN2) is also called Beclin-1-like protein 1/ BECN1P1 and it was recently identified by He et al 2013 as a mammal-specific homolog of the evolutionarily conserved protein Beclin 1 which is well established for its role in the regulation of autophagy and oncogenic suppression (1). He et al 2013 documented that human Beclin 2 is 57% similar to Beclin 1, and they confirmed its presence in several tissues including brain, placenta, thymus, uterus and skeletal muscles.