Nerve cells need a lot of energy and oxygen. They receive both through the blood. This is why nerve tissue is usually crisscrossed by a large number of blood vessels. But what prevents neurons and vascular cells from getting in each other's way as they grow? Researchers have identified a mechanism that takes care of this. The results have now appeared in the journal Neuron.
Nerve cells are extremely hungry. About one in five calories that we consume through food goes to our brain. This is because generating voltage pulses (the action potentials) and transmitting them between neurons is very energy-intensive. For this reason, nerve tissue is usually crisscrossed by numerous blood vessels. They ensure a supply of nutrients and oxygen.
During embryonic development, a large number of vessels sprout in the brain and spinal cord, but also in the retina of the eye. Additionally, masses of neurons are formed there, which network with each other and with structures such as muscles and organs. Both processes have to be considerate of each other so as not to get in each other's way. "We have identified a new mechanism that ensures this," explains the senior author.
"The appearance of blood vessels in the spinal cord begins in the animals about 8.5 days after fertilization," the author says. "Between days 10.5 and 12.5, however, blood vessels do not grow in all directions. This is despite the fact that large amounts of growth-promoting molecules are present in their environment during this time. Instead, during this time, numerous nerve cells - the motor neurons - migrate from their place of origin in the spinal cord to their final position. There, they then form extensions called axons that lead from the spine to the various targeting muscles."
This means that the motor neurons self-organize and grow at the time that blood vessels do not grow towards them. Only then after, do the vessels begin to sprout again. "The whole thing resembles a carefully choreographed dance," explains the doctoral student. "In the course of this, each partner takes care not to get in the other's way."
But how is this dance coordinated? Apparently, by the motor neurons shouting a "stop, now it's my turn" message to the vascular cells. To do this, they use a protein that they release into their environment - semaphorin 3C (Sema3C). It diffuses to the vascular cells and docks there at a receptor called PlexinD1 - in a sense, this is the ear for which the molecular message is intended.
"When we stop the production of Sema3C in neurons in mice, blood vessels form prematurely in the region where these neurons are located," explains the senior author. "This prevents the axons of the neurons from developing properly - they are prevented from doing so by the vessels." The researchers achieved a similar effect when they experimentally stopped the formation of PlexinD1 in the vascular cells: Since these were now deaf to the Sema3C signal from the neurons, they did not stop growing but continued to sprout.
The results document the importance of coordinated operation of the two processes during embryonic development. These findings could also contribute to a better understanding of certain diseases, such as retinal defects caused by strong and uncontrolled vessel growth. The use of the newly discovered mechanism may also potentially help in regenerating destroyed brain areas, for example after a spinal cord injury, in the long term.
https://www.cell.com/neuron/fulltext/S0896-6273(22)01078-9
http://sciencemission.com/site/index.php?page=news&type=view&id=publications%2Fendothelial-plexind1&filter=22
Spinal cord vascularization during motor neuron development
- 1,099 views
- Added
Latest News
Metabolic rewiring promotes…
By newseditor
Posted 18 Apr
A drug to prevent flu-induc…
By newseditor
Posted 18 Apr
New origin of deep brain waves
By newseditor
Posted 17 Apr
Starving cells hijack prote…
By newseditor
Posted 17 Apr
Miniature battery-free epid…
By newseditor
Posted 17 Apr
Other Top Stories
Genetic basis of tail-loss in humans
Read more
Autosomal dominant Alzheimer's disease and mechanisms of disease pr…
Read more
Genetic and biochemical determinants of brain calcification
Read more
The same protein controls brain size and infertility
Read more
Age-related cognitive decline tied to immune-system molecule
Read more
Protocols
MemPrep, a new technology f…
By newseditor
Posted 08 Apr
A tangible method to assess…
By newseditor
Posted 08 Apr
Stem cell-derived vessels-o…
By newseditor
Posted 06 Apr
Single-cell biclustering fo…
By newseditor
Posted 01 Apr
Modular dual-color BiAD sen…
By newseditor
Posted 31 Mar
Publications
Will cellular immunotherapi…
By newseditor
Posted 20 Apr
How does the microbiota con…
By newseditor
Posted 18 Apr
The integrated stress respo…
By newseditor
Posted 18 Apr
The immunobiology of herpes…
By newseditor
Posted 17 Apr
Circulating microbiome DNA…
By newseditor
Posted 17 Apr
Presentations
Hydrogels in Drug Delivery
By newseditor
Posted 12 Apr
Lipids
By newseditor
Posted 31 Dec
Cell biology of carbohydrat…
By newseditor
Posted 29 Nov
RNA interference (RNAi)
By newseditor
Posted 23 Oct
RNA structure and functions
By newseditor
Posted 19 Oct
Posters
A chemical biology/modular…
By newseditor
Posted 22 Aug
Single-molecule covalent ma…
By newseditor
Posted 04 Jul
ASCO-2020-HEALTH SERVICES R…
By newseditor
Posted 23 Mar
ASCO-2020-HEAD AND NECK CANCER
By newseditor
Posted 23 Mar
ASCO-2020-GENITOURINARY CAN…
By newseditor
Posted 23 Mar