spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online August 7, 2009
doi: 10.1242/10.1242/dev.037986

Development 136, 2923-2932 (2009)
Published by The Company of Biologists 2009
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Material
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Related articles in Development
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Song, M.-R.
Right arrow Articles by Pfaff, S. L.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Song, M.-R.
Right arrow Articles by Pfaff, S. L.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Islet-to-LMO stoichiometries control the function of transcription complexes that specify motor neuron and V2a interneuron identity

Mi-Ryoung Song1,2,*, Yunfu Sun3, Ami Bryson2, Gordon N. Gill3, Sylvia M. Evans3 and Samuel L. Pfaff2,*

1 Bioimaging Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea.
2 Howard Hughes Medical Institute and Gene Expression Laboratory, The Salk Institute, La Jolla, CA 92037, USA.
3 Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.

* Authors for correspondence (msong{at}gist.ac.kr; pfaff{at}salk.edu)

Accepted 23 June 2009

LIM transcription factors bind to nuclear LIM interactor (Ldb/NLI/Clim) in specific ratios to form higher-order complexes that regulate gene expression. Here we examined how the dosage of LIM homeodomain proteins Isl1 and Isl2 and LIM-only protein Lmo4 influences the assembly and function of complexes involved in the generation of spinal motor neurons (MNs) and V2a interneurons (INs). Reducing the levels of Islet proteins using a graded series of mutations favored V2a IN differentiation at the expense of MN formation. Although LIM-only proteins (LMOs) are predicted to antagonize the function of Islet proteins, we found that the presence or absence of Lmo4 had little influence on MN or V2a IN specification. We did find, however, that the loss of MNs resulting from reduced Islet levels was rescued by eliminating Lmo4, unmasking a functional interaction between these proteins. Our findings demonstrate that MN and V2a IN fates are specified by distinct complexes that are sensitive to the relative stoichiometries of the constituent factors and we present a model to explain how LIM domain proteins modulate these complexes and, thereby, this binary-cell-fate decision.

Key words: LIM transcription factor, Motor neuron, V2a interneuron, Cell-fate specification, Ldb (NLI, CLIM, Chip), Lmo4, Isl1, Isl2, Lhx3, Mouse, Chick


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?

Related articles in Development:

LIMiting concentrations for motor neurons...

Development 2009 136: e1703. [Full Text]  





© The Company of Biologists Ltd 2009