Campus Units

Biochemistry, Biophysics and Molecular Biology, Roy J. Carver Department of

Document Type

Article

Publication Version

Published Version

Publication Date

11-2004

Journal or Book Title

Molecular Biology of the Cell

Volume

15

Issue

11

First Page

4854

Last Page

4865

DOI

10.1091/mbc.e04-07-0579

Abstract

We have used immunocytochemistry and cross-immunoprecipitation analysis to demonstrate that Megator (Bx34 antigen), a Tpr ortholog in Drosophila with an extended coiled-coil domain, colocalizes with the putative spindle matrix proteins Skeletor and Chromator during mitosis. Analysis of P-element mutations in the Megator locus showed that Megator is an essential protein. During interphase Megator is localized to the nuclear rim and occupies the intranuclear space surrounding the chromosomes. However, during mitosis Megator reorganizes and aligns together with Skeletor and Chromator into a fusiform spindle structure. The Megator metaphase spindle persists in the absence of microtubule spindles, strongly implying that the existence of the Megator-defined spindle does not require polymerized microtubules. Deletion construct analysis in S2 cells indicates that the COOH-terminal part of Megator without the coiled-coil region was sufficient for both nuclear as well as spindle localization. In contrast, the NH2-terminal coiled-coil region remains in the cytoplasm; however, we show that it is capable of assembling into spherical structures. On the basis of these findings we propose that the COOH-terminal domain of Megator functions as a targeting and localization domain, whereas the NH2-terminal domain is responsible for forming polymers that may serve as a structural basis for the putative spindle matrix complex.

Comments

This article is published as Qi, Hongying, Uttama Rath, Dong Wang, Ying-Zhi Xu, Yun Ding, Weiguo Zhang, Melissa J. Blacketer et al. "Megator, an essential coiled-coil protein that localizes to the putative spindle matrix during mitosis in Drosophila." Molecular biology of the cell 15, no. 11 (2004): 4854-4865. doi: 10.1091/mbc.e04-07-0579.

Creative Commons License

Creative Commons Attribution-Noncommercial-Share Alike 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.

Copyright Owner

The American Society for Cell Biology

Language

en

File Format

application/pdf

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