Genetic mechanisms control the linear scaling between related cortical primary and higher order sensory areas
- The Salk Institute For Biological Studies, United States
- Minnesota State University Moorhead, United States
- University Medical Center, Germany
- King's College London, United Kingdom
- Academia Sinica, Taiwan
- Enthought Scientific Computing Solutions, United States
- University of California, San Francisco, United States
Abstract
In mammals, the neocortical layout consists of few modality-specific primary sensory areas and a multitude of higher order ones. Abnormal layout of cortical areas may disrupt sensory function and behavior. Developmental genetic mechanisms specify primary areas, but mechanisms influencing higher order area properties are unknown. By exploiting gain-of and loss-of function mouse models of the transcription factor Emx2, we have generated bi-directional changes in primary visual cortex size in vivo and have used it as a model to show a novel and prominent function for genetic mechanisms regulating primary visual area size and also proportionally dictating the sizes of surrounding higher order visual areas. This finding redefines the role for intrinsic genetic mechanisms to concomitantly specify and scale primary and related higher order sensory areas in a linear fashion.
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Animal experimentation: All experiments were approved under Protocol #09-012 and conducted following the guidelines of the Institutional Animal Care and Use Committee at the Salk Institute and were in full compliance with the guidelines of the National Institutes of Health for the care and use of laboratory animals.
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© 2015, Zembrzycki et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Genetic mechanisms control the linear scaling between related cortical primary and higher order sensory areas
eLife 4:e11416.
https://doi.org/10.7554/eLife.11416
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