A Role for Nusap in Linking Microtubules to Mitotic Chromosomes.
From: European Molecular Biology Laboratory, Meyerhofstrasse 1, D-69117 Heidelberg, Germany. katharina_ribbeck@hms.harvard.edu
Current biology : CB
- Publish Date: Feb 2007
- ISSN: 0960-9822
- Volume: 17
- Issue: 3
- Pages: 230-6
- Medium: Print
- Language: English
- Citation (JAMA): Ribbeck Katharina, Raemaekers Tim, Carmeliet Geert, et al. A Role for Nusap in Linking Microtubules to Mitotic Chromosomes.. Curr. Biol. Feb 2007;17:230-6
Abstract
The spindle apparatus is a microtubule (MT)-based machinery that attaches to and segregates the chromosomes during mitosis and meiosis. Self-organization of the spindle around chromatin involves the assembly of MTs, their attachment to the chromosomes, and their organization into a bipolar array. One regulator of spindle self-organization is RanGTP. RanGTP is generated at chromatin and activates a set of soluble, Ran-regulated spindle factors such as TPX2, NuMA, and NuSAP . How the spindle factors direct and attach MTs to the chromosomes are key open questions. Nucleolar and Spindle-Associated Protein (NuSAP) was recently identified as an essential MT-stabilizing and bundling protein that is enriched at the central part of the spindle . Here, we show by biochemical reconstitution that NuSAP efficiently adsorbs to isolated chromatin and DNA and that it can directly produce and retain high concentrations of MTs in the immediate vicinity of chromatin or DNA. Moreover, our data reveal that NuSAP-chromatin interaction is subject to Ran regulation and can be suppressed by Importin alpha (Impalpha) and Imp7. We propose that the presence of MT binding agents such as NuSAP, which can be directly immobilized on chromatin, are critical for targeting MT production to vertebrate chromosomes during spindle self-organization.
Mesh Headings (Keywords): Animals, Cell Line, Chromosomes, Chromosomes, Mammalian, DNA, Hela Cells, Humans, Karyopherins, Mice, Microtubule-Associated Proteins, Microtubules, Mitosis, Mitotic Spindle Apparatus, Oocytes, Recombinant Proteins, Xenopus Proteins, Xenopus laevis, ran GTP-Binding Protein
Check for Full Text / PubMed Unique Identifier (PMID): 17276916
This abstract is part of PubMed, a service of the U.S. National Library of Medicine. PubMed includes more than 17 million citations from MEDLINE and other life science journals for biomedical articles. See Copyright and Disclaimers.
Linked medical terms appearing on this page are added by Healia to help readers find more information and are not part of the original PubMed document.
The data herein was last updated on July 8th, 2008 and may not reflect the most current and accurate data available from NLM.