ATG5

The ATG5 protein belongs to the ATG autophagy regulator family. This family controls the highly conserved cell's homeostatic response to a wide variety of both self- and foreign-originating cellular stimuli. ATG5 itself is ubiquitously expressed in most cells and most often found co-localized with the cytoplasmic non-muscle actin protein under normal resting conditions. Upon activation of apoptosis, ATG5 expression is then dramatically intensified, with ATG5 directly complexing with its ATG family members to produce autophagosomes.

ATG5, or Autophagy Related 5, is a protein crucial for autophagy. Autophagy is a mechanism in which dysfunctional or pathogenic cells or cellular components are degraded and sometimes recycled. This process happens when ATG5 conjugates with another protein and associates with a cup shaped isolation membrane.

ATG5 is a member of the ATG family that regulates autophagy, the evolutionary conserved homeostatic response to a diverse variety of self- and foreign-originating cellular stresses. ATG5 is ubiquitously expressed in cells and found co-localized with cytoplasmic non-muscle actin under normal resting conditions, but upon the triggering of apoptosis, ATG5 expression dramatically ramps up, and ATG5 directly conjugates with other related ATG family proteins to form autophagosomes.

Autophagy is a conserved mechanism whereby cells form double membrane autophagosomes to sequester cytoplasmic components for subsequent destruction by fusion with lysosomes (eukaryotes) or vacuoles (yeast). Targets of autophagy include aging proteins, damaged organelles and invasive pathogens, and the resulting breakdown products can be recycled back to the cytoplasm for re-use under conditions of starvation (1).

Microtubule-associated protein light chain 3 (LC3) is considered one of the definitive markers of autophagy, and its use is widespread in labs throughout the world. Despite its popularity, there are several considerations when employing LC3 antibodies in immunoassays, Western blots in particular.

We at Novus Biologicals have a broad antibody database covering the area of autophagy - over 1400 reagents in total. Autophagy is the bulk degradation of cytoplasmic components - literally, self-digestion of the cell. Double-membrane vesicles, called autophagosomes, carry unwanted cell components to the lysosomes within an inner autophagic membrane. They then fuse, liberating the autophagic body and its contents into the lumen of the vacuole for degradation. This is a complex process involving at least 16 proteins.