TRAPPC3L encodes a trafficking protein particle complex subunit involved in vesicular transport. Based on limited published evidence, TRAPPC3L functions as a component of the TRAPP complex and mediates endoplasmic reticulum to Golgi transport and intra-Golgi vesicle trafficking through guanyl-nucleotide exchange factor activity. The protein localizes to the cis-Golgi network membrane and cytosol. One study identified TRAPPC3L downregulation and hypermethylation in aflatoxin B1-induced hepatocellular carcinoma transformation 1, suggesting potential involvement in cancer-related pathways, though mechanistic details remain unclear.