TIAM-1/GEF can shape somatosensory dendrites independently of its GEF activity by regulating F-actin localization

• DOI: 10.7554/elife.38949
• Publication Date: 2019-01-29T13:04:29Z
• Authors: Leo TH Tang; Carlos A Diaz-Balzac; Maisha Rahman; Nelson J Ramirez-...; Yehuda Salzberg; Maria I Lázaro-Peña; Hannes E Bülow
• Keywords: PDZ domain

Dendritic arbors are crucial for nervous system assembly, but the intracellular mechanisms that govern their assembly remain incompletely understood. Here, we show dendrites of PVD neurons in Caenorhabditis elegans patterned by distinct pathways downstream DMA-1 leucine-rich transmembrane (LRR-TM) receptor. DMA-1/LRR-TM interacts through a PDZ ligand motif with guanine nucleotide exchange factor TIAM-1/GEF complex act-4/Actin to pattern higher order 4° dendrite branches localizing F-actin distal ends developing dendrites. Surprisingly, appears function independently Rac1 activity. A partially redundant pathway, dependent on HPO-30/Claudin, regulates formation 2° and 3° branches, possibly regulating membrane localization trafficking DMA-1/LRR-TM. Collectively, our experiments suggest HPO-30/Claudin localizes receptor dendrites, which turn can control patterning directly modulating dynamics TIAM-1/GEF.