|
|
|
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Development, Vol 125, Issue 7 1337-1346, Copyright © 1998 by Company of Biologists
JOURNAL ARTICLES |
LS Rose and K Kemphues
Section of Genetics and Development, Cornell University, Ithaca, NY 14853, USA. lsrose@ucdavis.edu
The orientation of cell division is a critical aspect of development. In 2-cell C. elegans embryos, the spindle in the posterior cell is aligned along the long axis of the embryo and contributes to the unequal partitioning of cytoplasm, while the spindle in the anterior cell is oriented transverse to the long axis. Differing spindle alignments arise from blastomere-specific rotations of the nuclear-centrosome complex at prophase. We have found that mutations in the maternally expressed gene let-99 affect spindle orientation in all cells during the first three cleavages. During these divisions, the nuclear-centrosome complex appears unstable in position. In addition, in almost half of the mutant embryos, there are reversals of the normal pattern of spindle orientations at second cleavage: the spindle of the anterior cell is aligned with the long axis of the embryo and nuclear rotation fails in the posterior cell causing the spindle to form transverse to the long axis. In most of the remaining embryos, spindles in both cells are transverse at second cleavage. The distributions of several asymmetrically localized proteins, including P granules and PAR-3, are normal in early let-99 embryos, but are perturbed by the abnormal cell division orientations at second cleavage. The accumulation of actin and actin capping protein, which marks the site involved in nuclear rotation in 2-cell wild-type embryos, is abnormal but is not reversed in let-99 mutant embryos. Based on these data, we conclude that let-99(+) is required for the proper orientation of spindles after the establishment of polarity, and we postulate that let-99(+) plays a role in interactions between the astral microtubules and the cortical cytoskeleton.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati 
Twitter What's this?
This article has been cited by other articles:
|
|
 |
|
  W. Li, L. R. DeBella, T. Guven-Ozkan, R. Lin, and L. S. Rose An eIF4E-binding protein regulates katanin protein levels in C. elegans embryos J. Cell Biol., October 5, 2009; 187(1): 33 - 42. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. K. Baruni, E. M. Munro, and G. von Dassow Cytokinetic furrowing in toroidal, binucleate and anucleate cells in C. elegans embryos J. Cell Sci., February 1, 2008; 121(3): 306 - 316. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Kimura and S. Onami Local cortical pulling-force repression switches centrosomal centration and posterior displacement in C. elegans J. Cell Biol., December 31, 2007; 179(7): 1347 - 1354. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.-C. Wu and L. S. Rose PAR-3 and PAR-1 Inhibit LET-99 Localization to Generate a Cortical Band Important for Spindle Positioning in Caenorhabditis elegans Embryos Mol. Biol. Cell, November 1, 2007; 18(11): 4470 - 4482. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. B. Goulding, J. C. Canman, E. N. Senning, A. H. Marcus, and B. Bowerman Control of nuclear centration in the C. elegans zygote by receptor-independent G{alpha} signaling and myosin II J. Cell Biol., September 24, 2007; 178(7): 1177 - 1191. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. R. DeBella, A. Hayashi, and L. S. Rose LET-711, the Caenorhabditis elegans NOT1 Ortholog, Is Required for Spindle Positioning and Regulation of Microtubule Length in Embryos Mol. Biol. Cell, November 1, 2006; 17(11): 4911 - 4924. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M.-F. B. Tsou, A. Hayashi, and L. S. Rose LET-99 opposes G{alpha}/GPR signaling to generate asymmetry for spindle positioning in response to PAR and MES-1/SRC-1 signaling Development, December 1, 2003; 130(23): 5717 - 5730. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. C. Bergmann, M. Lee, B. Robertson, M.-F. B. Tsou, L. S. Rose, and W. B. Wood Embryonic handedness choice in C. elegans involves the G{alpha} protein GPA-16 Development, December 1, 2003; 130(23): 5731 - 5740. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Colombo, S. W. Grill, R. J. Kimple, F. S. Willard, D. P. Siderovski, and P. Gonczy Translation of Polarity Cues into Asymmetric Spindle Positioning in Caenorhabditis elegans Embryos Science, June 20, 2003; 300(5627): 1957 - 1961. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M.-F. B. Tsou, W. Ku, A. Hayashi, and L. S. Rose PAR-dependent and geometry-dependent mechanisms of spindle positioning J. Cell Biol., March 17, 2003; 160(6): 845 - 855. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M.-F. B. Tsou, A. Hayashi, L. R. DeBella, G. McGrath, and L. S. Rose LET-99 determines spindle position and is asymmetrically enriched in response to PAR polarity cues in C. elegans embryos Development, January 10, 2002; 129(19): 4469 - 4481. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-E. Gomes, S. E. Encalada, K. A. Swan, C. A. Shelton, J. C. Carter, and B. Bowerman The maternal gene spn-4 encodes a predicted RRM protein required for mitotic spindle orientation and cell fate patterning in early C. elegans embryos Development, November 1, 2001; 128(21): 4301 - 4314. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Berkowitz and S Strome MES-1, a protein required for unequal divisions of the germline in early C. elegans embryos, resembles receptor tyrosine kinases and is localized to the boundary between the germline and gut cells Development, January 10, 2000; 127(20): 4419 - 4431. [Abstract] [PDF]
|
|
|
|
|
|
P. Gonczy, H. Schnabel, T. Kaletta, A. D. Amores, T. Hyman, and R. Schnabel Dissection of Cell Division Processes in the One Cell Stage Caenorhabditis elegans Embryo by Mutational Analysis J. Cell Biol., March 8, 1999; 144(5): 927 - 946. [Abstract] [Full Text] [PDF]
|
|
