SEC24A is a component of the coat protein complex II (COPII) that plays a crucial role in endoplasmic reticulum (ER) to Golgi vesicular transport. As part of the COPII machinery, SEC24A promotes formation of transport vesicles from the ER and participates in cargo selection for transport to the Golgi complex 1. The protein shows selective cargo recognition, particularly for proteins containing cytoplasmic DxE or LxxLE motifs, and associates with SEC24B but not SEC24C and SEC24D 1. SEC24A demonstrates specific interactions with certain cargo proteins, notably serving as the cargo adaptor for PCSK9 secretion through its interaction with the ER export receptor SURF4 2. Complete genetic deficiency of SEC24A in mice is compatible with survival but results in markedly reduced plasma cholesterol due to impaired PCSK9 secretion and subsequent upregulation of hepatic LDLR levels 3. The protein has been implicated in disease contexts, including gastric cancer progression where it shows elevated expression in tumor tissues 4, and hepatitis B virus exploitation where HBV selectively uses SEC24A and SEC23B for viral envelope particle transport 5. These findings highlight SEC24A's importance in both normal cellular physiology and pathological processes.