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bioRxiv · 10.1101/2020.08.29.272369

Proximity labeling at non-centrosomal microtubule-organizing centers reveals VAB-10B and WDR-62 as distinct microtubule regulators

Sanchez, A. D.·Branon, T. C.·Cote, L. E.·Papagiannakis, A.·Liang, X.·Shen, K.·Jacobs-Wagner, C.·Ting, A. Y.·Feldman, J. L.
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Abstract

Reorganization of microtubules from the centrosome to non-centrosomal subcellular sites is central to cell differentiation. To identify components of non-centrosomal microtubule organizing centers in differentiated cells of a living organism, we developed the biotin ligase-based proximity labeling approach TurboID for use in C. elegans. We identified proteins proximal to the non-centrosomal microtubule minus end protein PTRN-1/Patronin at the apical membrane of epithelial cells, focusing on two conserved proteins: spectraplakin protein VAB-10B and WDR-62, a protein we identify as homologous to vertebrate primary microcephaly disease gene WDR62. We found that WDR-62 and VAB-10B independently regulate the growth and localization of non-centrosomal microtubules and the apical targeting of microtubule minus end proteins. This regulation occurs downstream of cell polarity and in conjunction with actin. Our data suggest a division of labor where microtubule growth and anchoring are regulated by distinct complexes and uncover novel functions of spectraplakins and WDR62 family proteins.

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Sanchez, A. D., Branon, T. C., Cote, L. E., Papagiannakis, A., Liang, X., Shen, K., Jacobs-Wagner, C., Ting, A. Y., Feldman, J. L.. 2020-08-29. Proximity labeling at non-centrosomal microtubule-organizing centers reveals VAB-10B and WDR-62 as distinct microtubule regulators. https://doi.org/10.1101/2020.08.29.272369

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