Semaphorins with class

Adams, R. H., Betz, H., and Piischel, A. W. (1996). A novel class of murine semaphorins with homology to thrombospondin is differentially expressed during early embryo-genesis. Mech. Dev. 57, 33-45. 

Vertebrate A-Plexins are the signaling subunits for secreted class 3 semaphorins, while other plexins interact with semaphorins from different classes (Fiore and Piischel, 2003). In contrast to SemaSA, which is not able to bind directly to A-Plexins, SemalD and Sema7A directly interact with Plexin-Bl and Plexin-Cl, respectively (Takahashi et al, 1999 Tamagnone et al, 1999). Interestingly, all Plexins contain an extracellular semaphorin domain that is strictly required for their function (Fig. 7). A semaphorin domain is also present in the scatter-factor receptor MET (Tamagnone et al, 1999). 

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