Open AccessTransient localization of the Arp2/3 complex initiates neuronal dendrite branching in vivo
Author(s) -
Tomke Stürner,
Anastasia Tatarnikova,
Jan O. Mueller,
Barbara Schaffran,
Hermann Cuntz,
Yun Zhang,
Maria Nemethova,
Sven Bogdan,
Vic Small,
Gaia Tavosanis
Publication year - 2019
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.754
H-Index - 325
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.171397
Subject(s) - biology , dendrite (mathematics) , microbiology and biotechnology , neuroscience , actin , morphogenesis , anatomy , genetics , geometry , mathematics , gene
The formation of neuronal dendrite branches is fundamental for the wiring and function of the nervous system. Indeed, dendrite branching enhances the coverage of the neuron's receptive field and modulates the initial processing of incoming stimuli. Complex dendrite patterns are achieved in vivo through a dynamic process of de novo branch formation, branch extension and retraction. The first step towards branch formation is the generation of a dynamic filopodium-like branchlet. The mechanisms underlying the initiation of dendrite branchlets are therefore crucial to the shaping of dendrites. Through in vivo time-lapse imaging of the subcellular localization of actin during the process of branching of Drosophila larva sensory neuron combined with genetic analysis and electron tomography we identified the (Actin related protein) Arp2/3 complex as the major actin-nucleator involved in the initiation of dendrite branchlet formation, under the control of the activator WAVE and of the small GTPase Rac1. Transient recruitment of an Arp2/3 component marks in vivo the site of branchlet initiation. These data position the activation of Arp2/3 as an early hub for the initiation of branchlet formation.