PUBLICATION

Loss of Llgl1 in retinal neuroepithelia reveals links between apical domain size, Notch activity and neurogenesis

Authors
Clark, B.S., Cui, S., Miesfeld, J.B., Klezovitch, O., Vasioukhin, V., and Link, B.A.
ID
ZDB-PUB-120702-2
Date
2012
Source
Development (Cambridge, England)   139(9): 1599-1610 (Journal)
Registered Authors
Clark, Brian, Cui, Shuang Alice, Link, Brian, Miesfeld, Joel B.
Keywords
neurogenesis, notch, zebrafish, lethal giant larvae, Shroom3, interkinetic nuclear migration, cell polarity
MeSH Terms
  • Animals
  • Bromodeoxyuridine
  • Cell Cycle Proteins/deficiency*
  • Cell Cycle Proteins/metabolism
  • Microfilament Proteins/metabolism
  • Neuroepithelial Cells/metabolism*
  • Neurogenesis/physiology*
  • Oligonucleotides/genetics
  • Receptors, Notch/metabolism*
  • Retina/cytology*
  • Time-Lapse Imaging
  • Zebrafish/metabolism
  • Zebrafish/physiology*
  • Zebrafish Proteins/deficiency*
  • Zebrafish Proteins/metabolism
PubMed
22492354 Full text @ Development
Abstract

To gain insights into the cellular mechanisms of neurogenesis, we analyzed retinal neuroepithelia deficient for Llgl1, a protein implicated in apicobasal cell polarity, asymmetric cell division, cell shape and cell cycle exit. We found that vertebrate retinal neuroepithelia deficient for Llgl1 retained overt apicobasal polarity, but had expanded apical domains. Llgl1 retinal progenitors also had increased Notch activity and reduced rates of neurogenesis. Blocking Notch function by depleting Rbpj restored normal neurogenesis. Experimental expansion of the apical domain, through inhibition of Shroom3, also increased Notch activity and reduced neurogenesis. Significantly, in wild-type retina, neurogenic retinal progenitors had smaller apical domains compared with proliferative neuroepithelia. As nuclear position during interkinetic nuclear migration (IKNM) has been previously linked with cell cycle exit, we analyzed this phenomenon in cells depleted of Llgl1. We found that although IKNM was normal, the relationship between nuclear position and neurogenesis was shifted away from the apical surface, consistent with increased pro-proliferative and/or anti-neurogenic signals associated with the apical domain. These data, in conjunction with other findings, suggest that, in retinal neuroepithelia, the size of the apical domain modulates the strength of polarized signals that influence neurogenesis.

Genes / Markers
Figures
Show all Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping