Scientists have reached an important milestone in understanding the complex mechanisms that control the development of the cerebral cortex, the part of the brain that plays a key role in attention, perception, consciousness, thought, memory, language, and consciousness.
Brains are composed of billions of neurons that communicate with each other by forming numerous connections and synapses. The cerebral cortex (multiple cortex) is the outermost layer of neural tissue of the cerebrum of the brain in humans and other mammals. Previous studies have shown that brain evolution in mammals was accompanied by a gradual enlargement of the cerebral cortex.
The intentional study, led by Prof. Lars Allan Larsen and Prof. Søren Tvorup Christensen at the University of Copenhagen (UCPH), Denmark, is published in Nature Communications.
The team started with genetic analyzes of a large family in which children were born with primary microcephaly, a rare congenital brain disease characterized by a reduction in the size of the cerebral cortex and varying degrees of cognitive dysfunction.
The scientists found that the children carried a mutation in both copies of the gene, RRP7A, and using stem cell cultures and zebrafish as a model organism, RRP7A was found to play a crucial role in brain stem cell proliferation. and form new neurons. This process is extremely complex and minor disruptions can have serious consequences, which may explain why the mutation affects the brain and not other tissues and organs.
“Our discovery is surprising because it reveals hitherto unknown mechanisms involved in brain development. In addition, it emphasizes the value of research on rare diseases, which is important for both the patients and families affected by the disease, but also beneficial to society in the form of new knowledge about human biology, ”said Prof Larsen, Department of Cellular and Molecular Medicine.
The researchers further found that the mutation in RRP7A affects the function of the so-called primary cilia, which in a single copy project as antenna-like structures on the surface of cells to register environmental cues and control the formation of new neurons in development. brain.
“Our results open a new way to understand how primary cilia control developmental processes, and how certain mutations on these antenna-like structures compromise the formation of tissues and organs during development. To this end, we have already initiated a series of studies to understand the mechanisms by which RRP7A regulates ciliary signaling to control the formation and organization of neurons in the brain, and how defects in this signaling can lead to brain malformation and cognitive impairment, said Prof. Christensen at Department of Biology.
Scientists discover a mechanism that regulates brain development
The cognitive abilities of the human brain increased in the course of evolution