Polarization of the anterior–posterior axis of c. Elegans is a microtubule-directed process

ABSTRACT In _Caenorhabditis elegans_, polarity along the anterior–posterior (A/P) axis is established shortly after fertilization and is determined by the sperm, whose position specifies the

posterior end of the embryo1. Although many factors required for the establishment of A/P polarity have been described2,3, the nature of the spatial cue provided by the sperm remains

unknown. Here we show that a microtubule-organizing centre is necessary and sufficient to establish several aspects of A/P polarity. In wild-type embryos, appearance of the first molecular

asymmetries along the A/P axis correlates with and requires nucleation of microtubules by the sperm-derived centrosomes (sperm asters). In mutant embryos arrested in meiosis, sperm asters

fail to form, and posterior is defined by the position of the persistent meiotic spindle rather than by the position of the sperm. Together, our data indicate that the primary spatial cue

for A/P polarity in _C. elegans _ derives from microtubules emanating from the sperm asters. Our findings support a parallel4,5,6,7 between _C. elegans_ zygotes and other cells, such as

_Drosophila_ oocytes, which rely on microtubules to regulate polarity. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution

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references ACKNOWLEDGEMENTS We are grateful to A. Golden, P. Sadler, J. Schumacher and D. Shakes for their characterization of the _mat_ mutants. We also thank K. O'Connell and J. White

for sharing results before publication; K. Kemphues and L. Boyd for antibodies; L. Timmons and A. Fire for RNAi feeding materials; and A. Golden, P. Sadler, D. Shakes, K. Kemphues, K. 

O'Connell, Y. Zheng and members of the Seydoux lab for comments on the manuscript. Some strains used in this study were provided by the Caenorhabditis Genetics Center (University of

Minnesota). M.R.W. was an NSF predoctoral fellow. This work was supported by grants from the Searle and Packard Foundations to G.S. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department

of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, 21205 , Maryland, USA Matthew R. Wallenfang & Geraldine Seydoux Authors * Matthew R. Wallenfang

View author publications You can also search for this author inPubMed Google Scholar * Geraldine Seydoux View author publications You can also search for this author inPubMed Google Scholar

CORRESPONDING AUTHOR Correspondence to Geraldine Seydoux. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Wallenfang, M., Seydoux, G. Polarization of

the anterior–posterior axis of _C. elegans_ is a microtubule-directed process. _Nature_ 408, 89–92 (2000). https://doi.org/10.1038/35040562 Download citation * Received: 10 May 2000 *

Accepted: 16 August 2000 * Issue Date: 02 November 2000 * DOI: https://doi.org/10.1038/35040562 SHARE THIS ARTICLE Anyone you share the following link with will be able to read this content:

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