High impact information on Sema-2a

• In the immune system, VESPR, a member of the Plexin family, is a receptor for a viral-encoded Semaphorin [1].
• The results show that semaphorin II can function in vivo as a selective target-derived signal that inhibits the formation of specific synaptic terminal arbors [2].
• The semaphorin genes encode a family of transmembrane and secreted growth cone guidance molecules [3].
• The expression patterns of the recently discovered family of semaphorin genes suggests that they have widespread roles in embryonic development [4].
• In this issue of Neuron, two beautiful studies in Drosophila by Lattemann et al. and Sweeney et al. show that Semaphorin repulsion regulates interactions between olfactory receptor neurons to help axons find their correct targets [5].

Anatomical context of Sema-2a

• A common theme in the mechanisms of semaphorin function is that they alter the cytoskeleton and the organization of actin filaments and the microtubule network [6].
• In this study, we show that the Drosophila Semaphorin-1a (Sema1a), a transmembrane Semaphorin, is required cell autonomously in adult photoreceptor (R-cell) axons for the establishment of an appropriate topographic termination pattern in the optic lobe [7].

References