World Library  

Add to Book Shelf
Flag as Inappropriate
Email this Book

Plos Biology : Three Distinct Roles for Notch in Drosophila R7 Photoreceptor Specification, Volume 9

By Desplan, Claude

Click here to view

Book Id: WPLBN0003952346
Format Type: PDF eBook :
File Size:
Reproduction Date: 2015

Title: Plos Biology : Three Distinct Roles for Notch in Drosophila R7 Photoreceptor Specification, Volume 9  
Author: Desplan, Claude
Volume: Volume 9
Language: English
Subject: Journals, Science, Biology
Collections: Periodicals: Journal and Magazine Collection (Contemporary), PLoS Biology
Publication Date:
Publisher: Plos


APA MLA Chicago

Desplan, C. (n.d.). Plos Biology : Three Distinct Roles for Notch in Drosophila R7 Photoreceptor Specification, Volume 9. Retrieved from

Description : Receptor tyrosine kinases (RTKs) and Notch (N) proteins are different types of transmembrane receptors that transduce extracellular signals and control cell fate. Here we examine cell fate specification in the Drosophila retina and ask how N acts together with the RTKs Sevenless (Sev) and the EGF receptor (DER) to specify the R7 photoreceptor. The retina is composed of many hundred ommatidia, each of which grows by recruiting surrounding, undifferentiated cells and directing them to particular fates. The R7 photoreceptor derives from a cohort of three cells that are incorporated together following specification of the R2-R5 and R8 photoreceptors. Two cells of the cohort are specified as the R1/6 photoreceptor type by DER activation. These cells then activate N in the third cell (the R7 precursor). By manipulation of N and RTK signaling in diverse combinations we establish three roles for N in specifying the R7 fate. The first role is to impose a block to photoreceptor differentiation: a block that DER activation cannot overcome. The second role, paradoxically, is to negate the first: Notch activation up-regulates Sev expression, enabling the presumptive R7 cell to receive an RTK signal from R8 that can override the block. The third role is to specify the cell as an R7 rather than an R1/6 once RTK signaling has specified the cells as a photoreceptor. We speculate why N acts both to block and to facilitate photoreceptor differentiation, and provide a model for how N and RTK signaling act combinatorially to specify the R1/6 and R7 photoreceptors as well as the surrounding non-neuronal cone cells.


Click To View

Additional Books

  • Plos Biology : the Evolution of Sex is F... (by )
  • Plos Biology : Polo-like Kinase 1 Direct... (by )
  • Plos Biology : Algorithmic Self-assembly... (by )
  • Plos Biology : Survival of Migrating Sal... (by )
  • Plos Biology : Jamm ; a Metalloprotease-... (by )
  • Plos Biology : Higher-order Oligomerizat... (by )
  • Plos Biology : Mechanisms of Aging in Bo... (by )
  • Plos Biology : the P75 Neurotrophin Rece... (by )
  • Plos Biology : Novel Melatonin-blocking ... (by )
  • Plos Biology : Experimental Evolution of... (by )
  • Plos Biology : the Evolution of Connecti... (by )
  • Plos Biology : Amplification of Trial-to... (by )
Scroll Left
Scroll Right


Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.