Datasheet

生物学的記述

Specificity	ATG4B Antibody [P14M3] detects endogenous levels of total ATG4B protein.
Background	ATG4B is a crucial cysteine protease in autophagy, responsible for processing and recycling ATG8 family proteins such as LC3 and GABARAP, thereby enabling autophagosome biogenesis across eukaryotes. ATG4B contains a catalytic triad composed of Cys74, Asp278, and His280 within a papain-like fold, with a regulatory loop and Trp142 that maintain the enzyme in an autoinhibited state until substrate engagement induces conformational changes for peptide bond hydrolysis. N-terminal motifs further enhance specificity for LC3 conjugated to phosphatidylethanolamine (PE) on autophagic membranes. ATG4B’s primary function is to expose the C-terminal glycine on pro-LC3 through an initial priming cleavage, preparing it for conjugation to PE via the ATG7/ATG3 ubiquitin-like cascade, and subsequently to catalyze the delipidation of LC3-PE on the outer autophagosomal membrane, facilitating the recycling of free LC3. With the broadest substrate selectivity among ATG4 paralogs, ATG4B primarily favors LC3, balancing autophagosome membrane elongation, tethering, and autophagic flux. Its activity is tightly regulated through redox modifications at Cys292 and Cys361 and by phosphorylation, adapting autophagy to cellular stress; overexpression of wild-type ATG4B can block LC3 lipidation by excessive deconjugation, while catalytically inactive mutants like C74A sequester LC3 and inhibit autophagy. Dysregulation of ATG4B activity is linked to tumorigenesis due to impaired autophagic flux.

Specificity

ATG4B Antibody [P14M3] detects endogenous levels of total ATG4B protein.

Background

ATG4B is a crucial cysteine protease in autophagy, responsible for processing and recycling ATG8 family proteins such as LC3 and GABARAP, thereby enabling autophagosome biogenesis across eukaryotes. ATG4B contains a catalytic triad composed of Cys74, Asp278, and His280 within a papain-like fold, with a regulatory loop and Trp142 that maintain the enzyme in an autoinhibited state until substrate engagement induces conformational changes for peptide bond hydrolysis. N-terminal motifs further enhance specificity for LC3 conjugated to phosphatidylethanolamine (PE) on autophagic membranes. ATG4B’s primary function is to expose the C-terminal glycine on pro-LC3 through an initial priming cleavage, preparing it for conjugation to PE via the ATG7/ATG3 ubiquitin-like cascade, and subsequently to catalyze the delipidation of LC3-PE on the outer autophagosomal membrane, facilitating the recycling of free LC3. With the broadest substrate selectivity among ATG4 paralogs, ATG4B primarily favors LC3, balancing autophagosome membrane elongation, tethering, and autophagic flux. Its activity is tightly regulated through redox modifications at Cys292 and Cys361 and by phosphorylation, adapting autophagy to cellular stress; overexpression of wild-type ATG4B can block LC3 lipidation by excessive deconjugation, while catalytically inactive mutants like C74A sequester LC3 and inhibit autophagy. Dysregulation of ATG4B activity is linked to tumorigenesis due to impaired autophagic flux.

使用情報

Application

WB, FCM

Dilution

WB	FCM
1:1000 - 1:10000	1:100 - 1:500

Reactivity

Mouse, Human

Source

Rabbit Monoclonal Antibody

MW

44 kDa

Storage Buffer

PBS, pH 7.2+50% Glycerol+0.05% BSA+0.01% NaN3

Storage
(from the date of receipt)

-20°C (avoid freeze-thaw cycles), 2 years

プロトコール

References

https://pubmed.ncbi.nlm.nih.gov/28901328/
https://pubmed.ncbi.nlm.nih.gov/35456009/

Application Data

WB

Validated by Selleck

Lane 1: Ramos, Lane 2: 293T, Lane 3: Jurkat, Lane 4: Hela