Semaphorin-5B (SEMA5B)

Semaphorin-5B is a transmembrane protein belonging to the class 5 semaphorin family, characterized by an N-terminal sema domain, a plexin-semaphorin-integrin (PSI) domain, and multiple (typically seven) thrombospondin type-1 repeats toward the C-terminus, with a short cytoplasmic region. This protein functions primarily as an axon guidance cue, playing a significant role in regulating axon growth, synapse development, and synapse elimination during postnatal and adult stages of nervous system development. SEMA5B can be proteolytically processed, resulting in the release of fragments containing the sema domain capable of regulating synaptic morphology through paracrine or autocrine signaling mechanisms. Its activity is context-dependent, with bifunctional effects on axon outgrowth influenced by extracellular matrix interactions (especially with proteoglycans), reminiscent of its homolog Sema5A. Persistent expression in the brain suggests a key role in neural circuit maintenance and synapse regulation. There is currently no evidence from the cited results for established drug interactions, recognized biomarkers, or prominent safety concerns in therapeutic contexts.

Other names

Semaphorin-5BSEMA5BKIAA1445SEMAGUNQ5867/PRO34001SemGFLJ10372semaphorin-5B(semaphorin) 5B

Not established for therapeutic drugs (no drugs identified), but SEMA5B fragments and domain interactions regulate synapse number and morphology