PMID- 17344225
OWN - NLM
STAT- MEDLINE
DCOM- 20070621
LR  - 20091119
IS  - 0950-1991 (Print)
IS  - 0950-1991 (Linking)
VI  - 134
IP  - 8
DP  - 2007 Apr
TI  - Ephrin-Eph signalling drives the asymmetric division of notochord/neural 
      precursors in Ciona embryos.
PG  - 1491-7
AB  - Asymmetric cell divisions produce two sibling cells with distinct fates, 
      providing an important means of generating cell diversity in developing embryos. 
      Many examples of such cell divisions have been described, but so far only a 
      limited number of the underlying mechanisms have been elucidated. Here, we have 
      uncovered a novel mechanism controlling an asymmetric cell division in the 
      ascidian embryo. This division produces one notochord and one neural precursor. 
      Differential activation of extracellular-signal-regulated kinase (ERK) between 
      the sibling cells determines their distinct fates, with ERK activation promoting 
      notochord fate. We first demonstrate that the segregation of notochord and neural 
      fates is an autonomous property of the mother cell and that the mother cell 
      acquires this functional polarity via interactions with neighbouring ectoderm 
      precursors. We show that these cellular interactions are mediated by the 
      ephrin-Eph signalling system, previously implicated in controlling cell movement 
      and adhesion. Disruption of contacts with the signalling cells or inhibition of 
      the ephrin-Eph signal results in the symmetric division of the mother cell, 
      generating two notochord precursors. Finally, we demonstrate that the ephrin-Eph 
      signal acts via attenuation of ERK activation in the neural-fated daughter cell. 
      We propose a model whereby directional ephrin-Eph signals functionally polarise 
      the notochord/neural mother cell, leading to asymmetric modulation of the 
      FGF-Ras-ERK pathway between the daughter cells and, thus, to their differential 
      fate specification.
FAU - Picco, Vincent
AU  - Picco V
AD  - Developmental Biology Unit, Universite Pierre et Marie Curie (Paris VI), CNRS, 
      Villefranche sur mer, France.
FAU - Hudson, Clare
AU  - Hudson C
FAU - Yasuo, Hitoyoshi
AU  - Yasuo H
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20070307
PL  - England
TA  - Development
JT  - Development (Cambridge, England)
JID - 8701744
RN  - 0 (Ephrins)
RN  - EC 2.7.10.1 (Receptors, Eph Family)
RN  - EC 2.7.11.24 (Extracellular Signal-Regulated MAP Kinases)
SB  - IM
MH  - Animals
MH  - Body Patterning
MH  - Cell Communication
MH  - Cell Division
MH  - Ciona intestinalis/*cytology/embryology
MH  - Ectoderm/cytology
MH  - Embryo, Nonmammalian/cytology
MH  - Enzyme Activation
MH  - Ephrins/*physiology
MH  - Extracellular Signal-Regulated MAP Kinases/metabolism
MH  - Neurons/cytology/metabolism
MH  - Notochord/*cytology/embryology/metabolism
MH  - Receptors, Eph Family/*physiology
MH  - Signal Transduction
MH  - Stem Cells/*cytology/metabolism
EDAT- 2007/03/09 09:00
MHDA- 2007/06/22 09:00
CRDT- 2007/03/09 09:00
PHST- 2007/03/09 09:00 [pubmed]
PHST- 2007/06/22 09:00 [medline]
PHST- 2007/03/09 09:00 [entrez]
AID - dev.003939 [pii]
AID - 10.1242/dev.003939 [doi]
PST - ppublish
SO  - Development. 2007 Apr;134(8):1491-7. doi: 10.1242/dev.003939. Epub 2007 Mar 7.