title: Chemical genetic identification of NDR1/2 kinase substrates AAK1 and Rabin8 Uncovers their roles in dendrite arborization and spine development.
abstract: Dendrite arborization and synapse formation are essential for wiring the neural circuitry. The evolutionarily conserved NDR1/2 kinase pathway, important for polarized growth from yeast to mammals, controls dendrite growth and morphology in the worm and fly. The function of NDR1/2 in mammalian neurons and their downstream effectors were not known. Here we show that the expression of dominant negative (kinase-dead) NDR1/2 mutants or siRNA increase dendrite length and proximal branching of mammalian pyramidal neurons in cultures and in vivo, whereas the expression of constitutively active NDR1/2 has the opposite effect. Moreover, NDR1/2 contributes to dendritic spine development and excitatory synaptic function. We further employed chemical genetics and identified NDR1/2 substrates in the brain, including two proteins involved in intracellular vesicle trafficking: AAK1 (AP-2 associated kinase) and Rabin8, a GDP/GTP exchange factor (GEF) of Rab8 GTPase. We finally show that AAK1 contributes to dendrite growth regulation, and Rabin8 regulates spine development.
authors.affiliation: Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143, USA. sila.ultanir@gmail.com
authors.forename: Sila K
authors.initials: SK
authors.lastname: Ultanir
authors.forename: Nicholas T
authors.initials: NT
authors.lastname: Hertz
authors.forename: Guangnan
authors.initials: G
authors.lastname: Li
authors.forename: Woo-Ping
authors.initials: WP
authors.lastname: Ge
authors.forename: Alma L
authors.initials: AL
authors.lastname: Burlingame
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Pleasure
authors.forename: Kevan M
authors.initials: KM
authors.lastname: Shokat
authors.forename: Lily Yeh
authors.initials: LY
authors.lastname: Jan
authors.forename: Yuh-Nung
authors.initials: YN
authors.lastname: Jan
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001324:Autoantigens / Q000378:metabolism; D002478:Cells, Cultured; D003712:Dendrites / Q000648:ultrastructure*; D049229:Dendritic Spines / Q000502:physiology*; D018274:Electroporation; D004622:Embryo, Mammalian; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008869:Microtubule-Associated Proteins; D008954:Models, Biological; D008958:Models, Molecular; D009154:Mutation / Q000235:genetics; D009474:Neurons / Q000166:cytology* / Q000502:physiology; D018408:Patch-Clamp Techniques; D010766:Phosphorylation / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D051381:Rats; D020318:Rats, Long-Evans; D013569:Synapses / Q000235:genetics / Q000502:physiology; D014162:Transfection; D000099259:N-myc Downstream-Regulated Gene 1 Protein
chemical_list: D001324:Autoantigens; D049452:Green Fluorescent Proteins; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D017346:Protein Serine-Threonine Kinases; D034741:RNA, Small Interfering; C097741:Golgin subfamily A member 2; C489787:MAP2 protein, rat; C562295:AAK1 protein, rat; C531302:Ndr2 protein, rat; C531303:Ndrg1 protein, rat; D000099259:N-myc Downstream-Regulated Gene 1 Protein