PAR-3 and PAR-1 inhibit LET-99 localization to generate a cortical band important for spindle positioning in Caenorhabditis elegans embryos

Jui Ching Wu, Lesilee S. Rose

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

The conserved PAR proteins are localized in asymmetric cortical domains and are required for the polarized localization of cell fate determinants in many organisms. In Caenorhabditis elegans embryos, LET-99 and G protein signaling act downstream of the PARs to regulate spindle positioning and ensure asymmetric division. PAR-3 and PAR-2 localize LET-99 to a posterior cortical band through an unknown mechanism. Here we report that LET-99 asymmetry depends on cortically localized PAR-1 and PAR-4 but not on cytoplasmic polarity effectors. In par-1 and par-4 embryos, LET-99 accumulates at the entire posterior cortex, but remains at low levels at the anterior cortex occupied by PAR-3. Further, PAR-3 and PAR-1 have graded cortical distributions with the highest levels at the anterior and posterior poles, respectively, and the lowest levels of these proteins correlate with high LET-99 accumulation. These results suggest that PAR-3 and PAR-1 inhibit the localization of LET-99 to generate a band pattern. In addition, PAR-1 kinase activity is required for the inhibition of LET-99 localization, and PAR-1 associates with LET-99. Finally, examination of par-1 embryos suggests that the banded pattern of LET-99 is critical for normal posterior spindle displacement and to prevent spindle misorientation caused by cell shape constraints.

Original languageEnglish (US)
Pages (from-to)4470-4482
Number of pages13
JournalMolecular Biology of the Cell
Volume18
Issue number11
DOIs
StatePublished - Nov 2007

Fingerprint

Linear Energy Transfer
Caenorhabditis elegans
Embryonic Structures
Cell Shape
GTP-Binding Proteins
Proteins
Phosphotransferases

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cell Biology

Cite this

PAR-3 and PAR-1 inhibit LET-99 localization to generate a cortical band important for spindle positioning in Caenorhabditis elegans embryos. / Wu, Jui Ching; Rose, Lesilee S.

In: Molecular Biology of the Cell, Vol. 18, No. 11, 11.2007, p. 4470-4482.

Research output: Contribution to journalArticle

@article{448555ec14af4e889951b9cce2463ff2,
title = "PAR-3 and PAR-1 inhibit LET-99 localization to generate a cortical band important for spindle positioning in Caenorhabditis elegans embryos",
abstract = "The conserved PAR proteins are localized in asymmetric cortical domains and are required for the polarized localization of cell fate determinants in many organisms. In Caenorhabditis elegans embryos, LET-99 and G protein signaling act downstream of the PARs to regulate spindle positioning and ensure asymmetric division. PAR-3 and PAR-2 localize LET-99 to a posterior cortical band through an unknown mechanism. Here we report that LET-99 asymmetry depends on cortically localized PAR-1 and PAR-4 but not on cytoplasmic polarity effectors. In par-1 and par-4 embryos, LET-99 accumulates at the entire posterior cortex, but remains at low levels at the anterior cortex occupied by PAR-3. Further, PAR-3 and PAR-1 have graded cortical distributions with the highest levels at the anterior and posterior poles, respectively, and the lowest levels of these proteins correlate with high LET-99 accumulation. These results suggest that PAR-3 and PAR-1 inhibit the localization of LET-99 to generate a band pattern. In addition, PAR-1 kinase activity is required for the inhibition of LET-99 localization, and PAR-1 associates with LET-99. Finally, examination of par-1 embryos suggests that the banded pattern of LET-99 is critical for normal posterior spindle displacement and to prevent spindle misorientation caused by cell shape constraints.",
author = "Wu, {Jui Ching} and Rose, {Lesilee S.}",
year = "2007",
month = "11",
doi = "10.1091/mbc.E07-02-0105",
language = "English (US)",
volume = "18",
pages = "4470--4482",
journal = "Molecular Biology of the Cell",
issn = "1059-1524",
publisher = "American Society for Cell Biology",
number = "11",

}

TY - JOUR

T1 - PAR-3 and PAR-1 inhibit LET-99 localization to generate a cortical band important for spindle positioning in Caenorhabditis elegans embryos

AU - Wu, Jui Ching

AU - Rose, Lesilee S.

PY - 2007/11

Y1 - 2007/11

N2 - The conserved PAR proteins are localized in asymmetric cortical domains and are required for the polarized localization of cell fate determinants in many organisms. In Caenorhabditis elegans embryos, LET-99 and G protein signaling act downstream of the PARs to regulate spindle positioning and ensure asymmetric division. PAR-3 and PAR-2 localize LET-99 to a posterior cortical band through an unknown mechanism. Here we report that LET-99 asymmetry depends on cortically localized PAR-1 and PAR-4 but not on cytoplasmic polarity effectors. In par-1 and par-4 embryos, LET-99 accumulates at the entire posterior cortex, but remains at low levels at the anterior cortex occupied by PAR-3. Further, PAR-3 and PAR-1 have graded cortical distributions with the highest levels at the anterior and posterior poles, respectively, and the lowest levels of these proteins correlate with high LET-99 accumulation. These results suggest that PAR-3 and PAR-1 inhibit the localization of LET-99 to generate a band pattern. In addition, PAR-1 kinase activity is required for the inhibition of LET-99 localization, and PAR-1 associates with LET-99. Finally, examination of par-1 embryos suggests that the banded pattern of LET-99 is critical for normal posterior spindle displacement and to prevent spindle misorientation caused by cell shape constraints.

AB - The conserved PAR proteins are localized in asymmetric cortical domains and are required for the polarized localization of cell fate determinants in many organisms. In Caenorhabditis elegans embryos, LET-99 and G protein signaling act downstream of the PARs to regulate spindle positioning and ensure asymmetric division. PAR-3 and PAR-2 localize LET-99 to a posterior cortical band through an unknown mechanism. Here we report that LET-99 asymmetry depends on cortically localized PAR-1 and PAR-4 but not on cytoplasmic polarity effectors. In par-1 and par-4 embryos, LET-99 accumulates at the entire posterior cortex, but remains at low levels at the anterior cortex occupied by PAR-3. Further, PAR-3 and PAR-1 have graded cortical distributions with the highest levels at the anterior and posterior poles, respectively, and the lowest levels of these proteins correlate with high LET-99 accumulation. These results suggest that PAR-3 and PAR-1 inhibit the localization of LET-99 to generate a band pattern. In addition, PAR-1 kinase activity is required for the inhibition of LET-99 localization, and PAR-1 associates with LET-99. Finally, examination of par-1 embryos suggests that the banded pattern of LET-99 is critical for normal posterior spindle displacement and to prevent spindle misorientation caused by cell shape constraints.

UR - http://www.scopus.com/inward/record.url?scp=35549011174&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=35549011174&partnerID=8YFLogxK

U2 - 10.1091/mbc.E07-02-0105

DO - 10.1091/mbc.E07-02-0105

M3 - Article

C2 - 17761536

AN - SCOPUS:35549011174

VL - 18

SP - 4470

EP - 4482

JO - Molecular Biology of the Cell

JF - Molecular Biology of the Cell

SN - 1059-1524

IS - 11

ER -