Sec18

Sec18 is a gene found in yeast, specifically Saccharomyces cerevisiae. It encodes a protein that plays a crucial role in the cell cycle. The Sec18 protein is an essential component of the secretory pathway, which is responsible for transporting proteins and lipids out of the cell or to various internal organelles. Specifically, Sec18 is an ATPase that functions as an unfoldase, a type of molecular chaperone. Its primary role is in the disassembly of protein complexes, a process vital for membrane fusion events during vesicle transport.

Sec18 acts as a homolog to the mammalian protein NSF (N-ethylmaleimide-sensitive factor). Both Sec18 and NSF are involved in the recycling of SNARE proteins, which are essential for mediating the fusion of vesicles with their target membranes. Without functional Sec18, yeast cells are unable to properly bud from their parent cell or transport newly synthesized proteins to the cell surface, leading to cell cycle arrest and eventually cell death. Mutations in the SEC18 gene can result in pleiotropic effects, impacting various cellular processes that rely on efficient vesicle trafficking. Research into Sec18 has provided significant insights into the fundamental mechanisms of protein secretion and membrane dynamics in eukaryotic cells.