RRC ID 80972
Author Bustillo ME, Douthit J, Astigarraga S, Treisman JE.
Title Two distinct mechanisms of Plexin A function in Drosophila optic lobe lamination and morphogenesis.
Journal Development
Abstract Visual circuit development is characterized by subdivision of neuropils into layers that house distinct sets of synaptic connections. We find that, in the Drosophila medulla, this layered organization depends on the axon guidance regulator Plexin A. In Plexin A null mutants, synaptic layers of the medulla neuropil and arborizations of individual neurons are wider and less distinct than in controls. Analysis of semaphorin function indicates that Semaphorin 1a, acting in a subset of medulla neurons, is the primary partner for Plexin A in medulla lamination. Removal of the cytoplasmic domain of endogenous Plexin A has little effect on the formation of medulla layers; however, both null and cytoplasmic domain deletion mutations of Plexin A result in an altered overall shape of the medulla neuropil. These data suggest that Plexin A acts as a receptor to mediate morphogenesis of the medulla neuropil, and as a ligand for Semaphorin 1a to subdivide it into layers. Its two independent functions illustrate how a few guidance molecules can organize complex brain structures by each playing multiple roles.
Volume 151(10)
Published 2024-5-15
DOI 10.1242/dev.202237
PII 352120
PMID 38738602
MeSH Animals Drosophila / embryology Drosophila / metabolism Drosophila Proteins* / genetics Drosophila Proteins* / metabolism Drosophila melanogaster / embryology Drosophila melanogaster / genetics Drosophila melanogaster / metabolism Morphogenesis* / genetics Mutation / genetics Nerve Tissue Proteins* / genetics Nerve Tissue Proteins* / metabolism Neurons / metabolism Neuropil* / metabolism Optic Lobe, Nonmammalian* / embryology Optic Lobe, Nonmammalian* / metabolism Receptors, Cell Surface* / genetics Receptors, Cell Surface* / metabolism Semaphorins* / genetics Semaphorins* / metabolism
Drosophila  M2L-3127