NuMA-microtubule interactions are critical for spindle orientation and the morphogenesis of diverse epidermal structures
Abstract
Mitotic spindle orientation is used to generate cell fate diversity and tissue architecture. A complex of NuMA and dynein/dynactin is required for robust spindle orientation in a number of cell types. Previous research proposed that dynein/dynactin was sufficient to generate forces on microtubules (MTs) to orient spindles, with NuMA acting as a passive tether. In this study, we demonstrate that dynein/dynactin is insufficient for spindle orientation and that NuMA's MT-binding domain, which targets MT tips, is also required. Loss of NuMA-MT interactions caused defects in spindle orientation and epidermal differentiation, leading to neonatal lethality. We also show that loss of NuMA-MT interactions disrupts spindle orientation in the hair follicle matrix, resulting in defective differentiation of matrix-derived lineages. Our results reveal an additional and direct function of NuMA during mitotic spindle positioning, as well as a reiterative use of spindle orientation in the skin to build diverse structures.
Article and author information
Author details
Reviewing Editor
- Yukiko M Yamashita, University of Michigan, United States
Ethics
Animal experimentation: All mouse studies were performed in accordance with our protocol (A147-15-05) approved by the Institutional Animal Care and Use Committee of Duke University (A147-15-05).
Version history
- Received: October 22, 2015
- Accepted: January 13, 2016
- Accepted Manuscript published: January 14, 2016 (version 1)
- Version of Record published: February 8, 2016 (version 2)
Copyright
© 2016, Seldin et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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