Gene behind your thoughts
doi:10.1038/nindia.2008.128 Published online 22 February 2008
Long before a child crawls out of the mother's womb, its thinking brain begins to shape. New research has pinned down the gene that guides this shaping up process. A gene called Lhx2 acts as a master regulator playing a vital role in the formation of cerebral cortex, the study suggests. The finding could open up new vistas in therapies for brain injuries and disorders.
Cerebral cortex is the brain region that controls higher sensory and cognitive functions including vision, language, decision-making, learning, and memory. If this gene remains silent, the nerve cells of cerebral cortex will not form.
The researchers used genetically altered mice to discover that Lhx2 acts during the time when the developing cortex exclusively teems with stem cells. They discovered Lhx2 must be allowed to function before 10 days of gestation, which is mid-way through the 19-day gestation period of the mouse. The cells in which the Lhx2 gene is turned off cannot ultimately become cerebral cortex cells. Instead, these cells cluster together to become a source of signals that instructs the neighbouring cortex cells to form hippocampus, a brain region vital for learning and memory.
"The study is significant as it shows how a very simple mechanism of signals and responses creates the most complex brain structures in the embryo," says Shubha Tole, one of the researchers. The team says this understanding of brain development would provide better insight into disorders caused by improper development such as autism, epilepsy, and schizophrenia.
- Mangale, V. S. et al. Lhx2 Selector Activity Specifies Cortical Identity and Suppresses Hippocampal Organizer Fate. Science 319, 304-309 (2008)