PMID- 12632175
OWN - NLM
STAT- MEDLINE
DCOM- 20030916
LR  - 20190613
IS  - 0949-944X (Print)
IS  - 0949-944X (Linking)
VI  - 213
IP  - 2
DP  - 2003 Mar
TI  - Snail is required for Delta endocytosis and Notch-dependent activation of 
      single-minded expression.
PG  - 65-72
AB  - In the Drosophila embryo, the mesectoderm corresponds to a single row of cells 
      abutting the mesoderm. It is specified by the expression of the single-minded 
      (sim) gene. The information that precisely positions the sim-expressing cells 
      along the dorso-ventral axis is incompletely understood. Previous studies have 
      shown that Dorsal and Twist activate sim expression in a large ventral domain, 
      while two negative regulators, Snail (Sna) and Suppressor of Hairless [Su(H)], 
      repress sim expression in the mesoderm and neuroectoderm, respectively. 
      Repression by Su(H) is relieved in the presumptive mesectoderm by Notch 
      signaling. In this paper, we show that Sna also has a positive regulatory 
      function on sim expression in the presumptive mesectoderm. This positive effect 
      of Sna depends on the Su(H)-binding sites within the sim promoter, suggesting 
      that Sna regulates Notch signaling. In addition, we find that Delta is 
      endocytosed together with the extracellular domain of Notch. The endocytosis of 
      Delta is only seen in the mesoderm and requires the activity of the sna and 
      neuralized (neur) genes. Interestingly, the Neur-mediated endocytosis of Delta 
      has recently been shown to be sufficient for the non-autonomous activation of 
      Notch target genes in wing imaginal discs. We therefore propose a novel model in 
      which Sna positions the mesectoderm via its dual regulatory activity. In this 
      model, Sna cell-autonomously represses sim expression in the mesoderm and 
      relieves Su(H)-dependent repression in a cell non-autonomous fashion by promoting 
      the Neur-dependent endocytosis of Delta in the mesoderm.
FAU - Morel, Veronique
AU  - Morel V
AD  - Ecole Normale Superieure, CNRS UMR 8542, 46 rue d'Ulm, 75230 Paris Cedex 05, 
      France.
FAU - Le Borgne, Roland
AU  - Le Borgne R
FAU - Schweisguth, Francois
AU  - Schweisguth F
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20030205
PL  - Germany
TA  - Dev Genes Evol
JT  - Development genes and evolution
JID - 9613264
RN  - 0 (Basic Helix-Loop-Helix Transcription Factors)
RN  - 0 (DNA-Binding Proteins)
RN  - 0 (Drosophila Proteins)
RN  - 0 (Intracellular Signaling Peptides and Proteins)
RN  - 0 (Membrane Proteins)
RN  - 0 (N protein, Drosophila)
RN  - 0 (Nuclear Proteins)
RN  - 0 (Receptors, Notch)
RN  - 0 (Snail Family Transcription Factors)
RN  - 0 (Transcription Factors)
RN  - 0 (delta protein)
RN  - 0 (sim protein, Drosophila)
RN  - 0 (sna protein, Drosophila)
SB  - IM
MH  - Animals
MH  - Basic Helix-Loop-Helix Transcription Factors
MH  - DNA-Binding Proteins/*biosynthesis/genetics/*physiology
MH  - Drosophila/*embryology/genetics/physiology
MH  - Drosophila Proteins/physiology
MH  - Embryo, Nonmammalian
MH  - Endocytosis
MH  - *Gene Expression Regulation, Developmental
MH  - Intracellular Signaling Peptides and Proteins
MH  - Membrane Proteins/*physiology
MH  - Nuclear Proteins/*biosynthesis/genetics
MH  - Receptors, Notch
MH  - Snail Family Transcription Factors
MH  - Transcription Factors/*physiology
EDAT- 2003/03/13 04:00
MHDA- 2003/09/17 05:00
CRDT- 2003/03/13 04:00
PHST- 2002/10/30 00:00 [received]
PHST- 2002/12/10 00:00 [accepted]
PHST- 2003/03/13 04:00 [pubmed]
PHST- 2003/09/17 05:00 [medline]
PHST- 2003/03/13 04:00 [entrez]
AID - 10.1007/s00427-003-0296-x [doi]
PST - ppublish
SO  - Dev Genes Evol. 2003 Mar;213(2):65-72. doi: 10.1007/s00427-003-0296-x. Epub 2003 
      Feb 5.