Qb-SNARE proteins are a subclass of SNARE (Soluble N-ethylmaleimide sensitive factor Attachment protein REceptor) proteins that play a crucial role in intracellular membrane fusion events, particularly in synaptic vesicle exocytosis. They are called Qb-SNAREs because they contain a conserved SNARE motif that is characterized by the presence of glutamine (Q) and bulky hydrophobic residues. Specifically, Qb-SNAREs contribute to the formation of the core SNARE complex along with Qc- and R-SNAREs, which brings two opposing membranes into close proximity, allowing for fusion and subsequent release of neurotransmitters or other vesicle contents. A well-known example of a Qb-SNARE protein is syntaxin 1B, which is abundantly expressed in neurons and interacts with synaptotagmin on the synaptic vesicle membrane to regulate calcium-dependent neurotransmitter release.