GRASP65

GRASP65 is a protein that in humans is encoded by the gene GORASP1. It is a member of the Golgi reassembly stacking protein family, which plays a critical role in the maintenance of the Golgi apparatus structure. GRASP65 is primarily known for its involvement in the stacking of Golgi cisternae and in the process of Golgi reassembly during the cell cycle.

Function

GRASP65 is located on the cytoplasmic face of the Golgi membrane and is involved in the stacking of Golgi cisternae and in the maintenance of the structural integrity of the Golgi apparatus. It functions by forming oligomers and then cross-linking Golgi membranes. In addition to its structural role, GRASP65 is implicated in the regulation of Golgi ribbon linking and in the mitotic breakdown of the Golgi apparatus. During mitosis, GRASP65 is phosphorylated, which leads to the disassembly of the Golgi stack, facilitating its distribution into daughter cells.

Structure

The GRASP65 protein contains a PDZ domain, which is involved in protein-protein interactions. This domain allows GRASP65 to bind to other Golgi proteins and form the necessary complexes for Golgi stacking and maintenance. The protein also has a coiled-coil domain that is essential for its oligomerization and function.

Clinical Significance

Alterations in the expression or function of GRASP65 have been linked to various diseases, including neurological disorders and cancer. Abnormalities in Golgi structure and function can affect cell signaling, protein trafficking, and apoptosis, leading to disease pathogenesis. Research into GRASP65 and its interactions with other Golgi proteins may provide insights into novel therapeutic targets for these conditions.

Research

Studies on GRASP65 have contributed to a broader understanding of Golgi apparatus dynamics, especially its reassembly during the cell cycle and its role in disease. Ongoing research is focused on elucidating the precise mechanisms by which GRASP65 and other Golgi-associated proteins regulate Golgi structure and function, as well as their implications for human health and disease.