TRARG1 (trafficking regulator of GLUT4-1) is a transmembrane protein that regulates insulin-mediated glucose uptake in adipose tissue by modulating GLUT4 recycling and trafficking 1. The protein contains one transmembrane domain and a re-entrant loop, with its N-terminus facing the cytoplasm and C-terminus in the luminal space 2. TRARG1 functions as a substrate for GSK3 kinase and undergoes dephosphorylation in response to insulin through a PI3K/Akt-dependent pathway 1. This phosphorylation regulation is critical for proper GLUT4 trafficking, as pharmacological GSK3 inhibition increases cell surface GLUT4 in a TRARG1-dependent manner 1. TRARG1 is abundantly expressed in adipose tissues, with expression patterns that differ between lean and obese states 3. The gene belongs to the dispanin family of transmembrane proteins and may have additional roles in peripheral nervous system function 4. Disease relevance includes potential involvement in metabolic disorders through its role in insulin sensitivity, and genetic variants near TRARG1 have been associated with intestinal malrotation in genome-wide association studies 5. The protein represents an important component of the insulin signaling network regulating glucose homeostasis.