Human TUBB3 Mutations Disrupt Netrin Attractive Signaling. (15th March 2018)

• Record Type: Journal Article
• Authors: Huang, Huai; Yang, Tao; Shao, Qiangqiang; Majumder, Tanushree; Mell, Kristopher; Liu, Guofa
• Is Part Of: Neuroscience. Volume 374(2018)
• Page Start: 155
• Page End: 171
• Publication Date: 2018-03-15
• Subjects: CA commissural axon -- co-IP co-immunoprecipitation -- DCC deleted in colorectal cancer -- DSCAM Down syndrome cell adhesion molecule -- MT microtubule -- PAGE polyacrylamide gel electrophoresis -- PCC Pearson's Correlation Coefficient -- PFA paraformaldehyde -- ROI region of interest -- UNC5 uncoordinated-5 -- UTR 3′ untranslated region -- YFP yellow fluorescent protein; netrin-1 -- DCC -- TUBB3 -- missense mutations -- signal transduction -- axon guidance; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2018.01.046
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: TUBB3 mutations impair the interaction of DCC with TUBB3. TUBB3 mutations perturb netrin-1-induced interaction of DCC with polymerized TUBB3 in MTs. TUBB3 mutations block netrin-1-induced neurite outgrowth and branching. TUBB3 mutations inhibit netrin-1-promoted commissural axon attraction. TUBB3 mutations impair spinal cord commissural axon projection in vivo. Abstract: Heterozygous missense mutations in human TUBB3 gene result in a spectrum of brain malformations associated with defects in axon guidance, neuronal migration and differentiation. However, the molecular mechanisms underlying mutation-related axon guidance abnormalities are unclear. Recent studies have shown that netrin-1, a canonical guidance cue, induced the interaction of TUBB3 with the netrin receptor deleted in colorectal cancer (DCC). Furthermore, TUBB3 is required for netrin-1-induced axon outgrowth, branching and pathfinding. Here, we provide evidence that TUBB3 mutations impair netrin/DCC signaling in the developing nervous system. The interaction of DCC with most TUBB3 mutants (eight out of twelve) is significantly reduced compared to the wild-type TUBB3. TUBB3 mutants R262C and A302V exhibit decreased subcellular colocalization with DCC in the growth cones of primary neurons. Netrin-1 increases the interaction of endogenous DCC with wild-type human TUBB3, but not R262C or A302V, in primary neurons. Netrin-1 also increases co-sedimentation of DCC with polymerized microtubules (MTs) in primary neurons expressing the wild-type TUBB3, but not R262C or A302V. Expression of either R262C or A302V not only suppresses netrin-1-induced neurite outgrowth, branching and attraction in vitro, but also causes defects in spinal cord commissural axon (CA) projection and pathfinding in ovo . Our study reveals that missense TUBB3 mutations specifically disrupt netrin/DCC-mediated attractive signaling.