MAP1LC3B Antibody – Rabbit Polyclonal

Function: Ubiquitin-like modifier involved in formation of autophagosomal vacuoles (autophagosomes). Plays a role in mitophagy which contributes to regulate mitochondrial quantity and quality by eliminating the mitochondria to a basal level to fulfill cellular energy requirements and preventing excess ROS production. Whereas LC3s are involved in elongation of the phagophore membrane, the GABARAP/GATE-16 subfamily is essential for a later stage in autophagosome maturation. Ref.11 Ref.20

Subunit structure: 3 different light chains, LC1, LC2 and LC3, can associate with MAP1A and MAP1B proteins

By similarity. Interacts at microtubules with CABP1 (via EF-hands 1 and 2) but not with calmodulin. Interacts with FYCO1 (via C-terminus). Interacts with TP53INP1 and TP53INP2. Interacts with TBC1D25. Directly interacts with SQSTM1; this interaction leads to MAP1LC3B recruitment to inclusion bodies containing polyubiquitinated protein aggregates and to inclusion body degradation by autophagy. Interacts with ATG4B, MAPK15 and BNIP3. Interacts with TECPR2. Ref.9 Ref.10 Ref.12 Ref.13 Ref.14 Ref.15 Ref.17 Ref.20

Subcellular location: Cytoplasm › cytoskeleton. Endomembrane system; Lipid-anchor. Cytoplasmic vesicle › autophagosome membrane; Lipid-anchor. Note: LC3-II binds to the autophagic membranes. Ref.3 Ref.10 Ref.16

Tissue specificity: Most abundant in heart, brain, skeletal muscle and testis. Little expression observed in liver. Ref.3

Post-translational modification: The precursor molecule is cleaved by ATG4B to form the cytosolic form, LC3-I. This is activated by APG7L/ATG7, transferred to ATG3 and conjugated to phospholipid to form the membrane-bound form, LC3-II. Ref.3 Ref.6 Ref.7 Ref.19The Legionella effector RavZ is a deconjugating enzyme that produces an ATG8 product that would be resistant to reconjugation by the host machinery due to the cleavage of the reactive C-terminal glycine.Phosphorylation at Thr-12 by PKA inhibits conjugation to phosphatidylethanolamine (PE)

By similarity. Interaction with MAPK15 reduces the inhibitory phosphorylation and increases autophagy activity.

Sequence similarities: Belongs to the ATG8 family.

Caution: Ref.3 has shown that the protein is cleaved at Lys-122 but Ref.7 has shown that the cleavage site is at Gly-120 as in other mammalian orthologs.