Pseudophosphatase STYXL1 depletion enhances glucocerebrosidase trafficking to lysosomes via ER stress.

Pseudophosphatases are catalytically inactive but share sequence and structural similarities with classical phosphatases. STYXL1 is a pseudophosphatase that belongs to the family of dual-specificity phosphatases and is known to regulate stress granule formation, neurite formation and apoptosis in different cell types. However, the role of STYXL1 in regulating cellular trafficking or the lysosome function has not been elucidated.

The Microscopy-Based Assay to Study and Analyze the Recycling Endosomes using SNARE Trafficking.

Recycling endosomes (REs) are tubular-vesicular organelles generated from early/sorting endosomes in all cell types. These organelles play a key role in the biogenesis of melanosomes, a lysosome-related organelle produced by melanocytes. REs deliver the melanocyte-specific cargo to premature melanosomes during their formation.

Rab22A recruits BLOC-1 and BLOC-2 to promote the biogenesis of recycling endosomes.

Recycling endosomes (REs) are transient endosomal tubular intermediates of early/sorting endosomes (E/SEs) that function in cargo recycling to the cell surface and deliver the cell type-specific cargo to lysosome-related organelles such as melanosomes in melanocytes. However, the mechanism of RE biogenesis is largely unknown. In this study, by using an endosomal Rab-specific RNAi screen, we identified Rab22A as a critical player during RE biogenesis.