Neurexin and neuroligin-based adhesion complexes drive axonal arborisation growth independent of synaptic activity

TY - JOUR

T1 - Neurexin and neuroligin-based adhesion complexes drive axonal arborisation growth independent of synaptic activity

AU - Constance, William D.

AU - Mukherjee, Amrita

AU - Fisher, Yvette E.

AU - Pop, Sinziana

AU - Blanc, Eric

AU - Toyama, Yusuke

AU - Williams, Darren W.

PY - 2018/3/5

Y1 - 2018/3/5

N2 - Building arborisations of the right size and shape is fundamental for neural network function. Live imaging in vertebrate brains strongly suggests that nascent synapses are critical for branch growth during development. The molecular mechanisms underlying this are largely unknown. Here we present a novel system in Drosophila for studying the development of complex arborisations live, in vivo during metamorphosis. In growing arborisations we see branch dynamics and localisations of presynaptic proteins very similar to the ‘synaptotropic growth’ described in fish/frogs. These accumulations of presynaptic proteins do not appear to be presynaptic release sites and are not paired with neurotransmitter receptors. Knockdowns of either evoked or spontaneous neurotransmission do not impact arbor growth. Instead, we find that axonal branch growth is regulated by dynamic, focal localisations of Neurexin and Neuroligin. These adhesion complexes provide stability for filopodia by a ‘stick-and-grow’ based mechanism wholly independent of synaptic activity.

AB - Building arborisations of the right size and shape is fundamental for neural network function. Live imaging in vertebrate brains strongly suggests that nascent synapses are critical for branch growth during development. The molecular mechanisms underlying this are largely unknown. Here we present a novel system in Drosophila for studying the development of complex arborisations live, in vivo during metamorphosis. In growing arborisations we see branch dynamics and localisations of presynaptic proteins very similar to the ‘synaptotropic growth’ described in fish/frogs. These accumulations of presynaptic proteins do not appear to be presynaptic release sites and are not paired with neurotransmitter receptors. Knockdowns of either evoked or spontaneous neurotransmission do not impact arbor growth. Instead, we find that axonal branch growth is regulated by dynamic, focal localisations of Neurexin and Neuroligin. These adhesion complexes provide stability for filopodia by a ‘stick-and-grow’ based mechanism wholly independent of synaptic activity.

UR - http://www.scopus.com/inward/record.url?scp=85045656584&partnerID=8YFLogxK

U2 - 10.7554/eLife.31659

DO - 10.7554/eLife.31659

M3 - Article

AN - SCOPUS:85045656584

SN - 2050-084X

VL - 7

JO - eLife

JF - eLife

M1 - e31659

ER -