GLL23 Antibody

Introduction to GLL23 Antibody

GLL23 Antibody refers to research tools used to study the trafficking, localization, and functional mechanisms of GLL23, a 43 kDa GDSL-like lipase in Arabidopsis thaliana. This antibody enables visualization and biochemical analysis of GLL23, particularly in mutants with disrupted intracellular transport pathways. GLL23 associates with myrosinase, a β-glucosidase critical for glucosinolate metabolism, which impacts plant defense and secondary metabolism .

Role of GLL23 Antibody in Trafficking Studies

GLL23 Antibody has been pivotal in identifying two distinct trafficking defects:

• ER Accumulation in nuc Mutants: In the nuclear cage (nuc) mutant, GLL23 aggregates in perinuclear ER compartments due to the loss of NUC/MVP1/GOLD36/ERMO3, a myrosinase-associated protein. Live imaging confirmed GLL23’s retention in these structures, suggesting NUC facilitates ER export or processing .

• Cytoplasmic Body Formation in cyb Mutants: In the cytoplasmic bodies (cyb) mutant, GLL23 accumulates in small compartments contiguous with the peripheral ER. This phenotype arises from the loss of CYB, a p24 protein involved in coat protein complex (COP) vesicle-mediated ER-Golgi transport .

Table 1: Mutant Phenotypes and Trafficking Defects

NUC’s Role in ER Processing

NUC, initially identified as vacuolar-localized, is unexpectedly active in the ER for GLL23 processing. In nuc mutants, GLL23 fails to undergo post-translational modifications required for export, leading to ER retention . This highlights a dual role for NUC in both ER processing and vacuolar targeting.

CYB’s Role in ER-Golgi Export

CYB, a p24 protein, is critical for selective cargo sorting into COP vesicles. In cyb mutants, both GLL23 and NUC accumulate in cytoplasmic bodies, indicating that CYB facilitates their export. Animal and yeast homologs of CYB are known to mediate cargo selection, suggesting conserved mechanisms across eukaryotes .

Table 2: Key Proteins in GLL23 Trafficking

Implications for Plant Metabolism

GLL23’s association with myrosinase links its trafficking to glucosinolate activation, a defense mechanism against pathogens. Mis-trafficking in mutants disrupts this pathway, underscoring the importance of NUC and CYB in maintaining cellular homeostasis. These findings also highlight the interplay between ER quality control and vacuolar targeting in plants .