Biotin Availability Modulates Transglutaminase Expression and Activity during Lipid Accumulation in 3T3-F442A Adipocytes.

Biotin deficiency impairs lipid accumulation in 3T3-F442A adipocytes despite allowing adipocyte differentiation. Here, we examined whether transglutaminase, a cytoskeletal remodeling enzyme associated with lipid droplets, is affected by biotin availability. Under biotin-deficient conditions, adipocytes showed reduced lipid droplet formation, cytoplasmic empty vesicle-like structures, and decreased transglutaminase expression and activity. Pharmacological inhibition of transglutaminase reduced lipid accumulation and decreased malic enzyme activity, suggesting a link between transglutaminase activity and NADPH-dependent lipogenesis. These findings identify transglutaminase as a biotin-sensitive component associated with lipid accumulation in 3T3-F442A adipocytes.