TRAPPC13 Antibody

TRAPPC13 Antibody: Definition and Applications

TRAPPC13 antibodies are polyclonal or monoclonal antibodies specifically targeting the TRAPPC13 protein, which is part of the TRAPPIII complex in humans. These antibodies are utilized in techniques such as:

• Western blotting (detecting endogenous TRAPPC13 in cell lysates)

• Immunofluorescence microscopy (localizing TRAPPC13 to Golgi and ER-associated compartments)

• Co-immunoprecipitation (Co-IP) (identifying TRAPPC13 interaction partners like TRAPPC3, TRAPPC4, and Rab1 GTPases)

• Functional studies (assessing autophagy flux and Golgi integrity under stress conditions)

Role in Autophagy and Golgi Stress Resistance

• Autophagy regulation: TRAPPC13 depletion reduces Rab1a/b GTPase activity, impairing autophagosome formation and flux . Antibody-based assays confirmed that TRAPPC13 knockdown cells exhibit diminished LC3-II accumulation under brefeldin A (BFA) treatment, indicating defective autophagy .

• Golgi stress survival: Cells lacking TRAPPC13 show resistance to Golgi-disrupting agents (e.g., BFA, golgicide A) due to preserved ARF1-GBF1 activity and reduced ER stress . Immunofluorescence using TRAPPC13 antibodies revealed less fragmented Golgi structures in knockdown cells during BFA exposure .

Interaction With Pathogens

• TRAPPC13 antibodies identified its interaction with Shigella flexneri, a bacterial pathogen. Depletion of TRAPPC13 increases bacterial infectivity by impairing autophagy-mediated clearance .

• In plants, TRAPPC13 interacts with Mesorhizobium amorphae effector protein NopP, as shown by yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays .

Table 1: TRAPPC13 Antibody Applications and Outcomes

Mechanistic Insights

• TRAPP complex integrity: TRAPPC13 antibodies confirmed that TRAPPC13 loss does not disrupt core TRAPP complex assembly but reduces Rab1 activation, critical for autophagosome maturation .

• ARF1 dependency: Antibody-based ARF-GTP pulldown assays showed TRAPPC13 knockdown maintains ARF1 activity during BFA treatment, enabling secretory pathway preservation .

Research Implications

TRAPPC13 antibodies have proven essential in elucidating:

• The TRAPPIII complex’s role as a Rab1 GEF in metazoans.

• Cross-talk between Golgi stress, autophagy, and pathogen susceptibility.

• Evolutionary divergence (e.g., TRAPPC13 is TRAPPII-associated in yeast but TRAPPIII-specific in mammals) .