syntaxin17

Syntaxin 17 (STX17) is a member of the syntaxin family of SNARE proteins. In humans, the STX17 gene encodes this tail-anchored membrane protein. STX17 is anchored in membranes by a C-terminal transmembrane domain and localizes predominantly to autophagosomal membranes, with additional presence at lysosomes and, under some conditions, mitochondria-associated membranes.

Functionally, STX17 plays an essential role in autophagy by promoting the fusion of mature autophagosomes with lysosomes. It acts as a target membrane (t-SNARE) that forms a SNARE complex with its partners SNAP29 and VAMP8 to drive membrane fusion. This complex facilitates the delivery of autophagic cargo to lysosomes for degradation and recycling of macromolecules. The recruitment of STX17 to autophagosomes is a key maturation step in autophagy.

Regulation and interactions of STX17 are tied to cellular nutrient status and signaling pathways that control autophagy. The protein can interact with additional SNAREs and tethering factors, and disruptions in STX17 function impair autophagic flux, leading to accumulation of autophagosomes or impaired cargo degradation.

Clinical and research notes indicate that because autophagy participates in many physiological and pathological processes, STX17 has been studied in contexts such as neurodegenerative diseases, cancer, and host–pathogen interactions. Ongoing research aims to clarify its regulatory mechanisms and assess its potential as a therapeutic target to modulate autophagy.