LAPosome Antibody Sampler Kit

Background

LC3-associated phagocytosis (LAP) is a process at the crossroads between autophagy and phagocytosis in which uptake of extracellular particles into phagophores utilizes components of the autophagic machinery and is targeted to the lysosome for degradation (reviewed in 1-3). Activation of LAP by infectious agents through engagement of pathogen receptors like Toll-like receptors (TLRs) are important in immune regulation and host defense. While autophagosomes and LAP phagophores both express lipidated LC3, autophagosomes are double membrane vesicles while the phagophores in LAP are single membrane. While LAP shares some components of canonical autophagy, there are some distinct differences. Both autophagy and LAP require PI3 Kinase Class III (PI3KC3; also known as VPS34) as well as the regulatory protein PIK3R4 (also known as VPS15) and Beclin-1. However, while canonical autophagy requires Atg14 and Ambra-1 in this complex, LAP requires Rubicon and UVRAG. This complex, known as the LAPosome, activates PI3KC3 and triggers nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2), generating reactive oxygen species (ROS) for phagophore maturation. The expression of Rubicon in this complex has emerged as a defining characteristic of LAP.