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Published on: February 2, 2016
Lhx2 regulates the development of the forebrain hem system
Achira Roy1, Miriam Gonzalez-Gomez, Alessandra Pierani
1Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.
Cerebral Cortex (New York, N.Y. : 1991)
|January 12, 2013
Summary
The transcription factor Lhx2 is crucial for regulating early brain development by controlling the size of three key forebrain signaling centers. Its absence leads to expanded structures and increased Cajal-Retzius cells, potentially causing malformations.
Area of Science:
- Neuroscience
- Developmental Biology
- Genetics
Background:
- Early brain development relies on coordinated signaling centers at compartment boundaries.
- Three telencephalic midline structures—cortical hem, septum, and thalamic eminence—are critical for forebrain patterning.
- Cajal-Retzius cells, produced by these structures, are thought to migrate and influence patterning.
Purpose of the Study:
- To investigate the role of the transcription factor Lhx2 in regulating the development of telencephalic midline structures.
- To understand how Lhx2 controls the extent of the cortical hem, septum, and thalamic eminence.
- To explore the implications of disruptions in this system for brain malformations and evolution.
Main Methods:
- Analysis of Lhx2 function in early brain development.
- Examination of the impact of Lhx2 absence on telencephalic midline structures.
- Assessment of Cajal-Retzius cell populations and migration patterns.
Main Results:
- Lhx2 is required to delimit the extent of the cortical hem, septum, and thalamic eminence.
- Loss of Lhx2 function leads to significant expansion of these three structures.
- The Cajal-Retzius cell population is dramatically increased in the absence of Lhx2.
Conclusions:
- The cortical hem, septum, and thalamic eminence form a 'forebrain hem system' regulated by Lhx2.
- This system is essential for defining and regulating the telencephalic midline.
- Dysregulation of the forebrain hem system may contribute to brain malformations like holoprosencephaly and has implications for forebrain evolution.
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