"Checkpoints" and "Molecular Sieves" Make Protein Molecules Go the Right Way
n order to improve the efficiency of information processing, the parts of our nerve cells that receive information and issue instructions are separated. This requires protein molecules that "run errands" for information to find their correct location. In the past, it was generally believed that it was because the protein molecules related to signal processing were “smart” and would automatically find the “direction”, but Shanghai scientists recently discovered that our neurons set up a clever “checkpoint”-molecular sieve, This flexible net can identify the "identity" of molecules, allowing protein molecules to go the right way, enter the right door, and do the right thing. Today's "Cell" magazine published this breakthrough discovery made by researchers Pu Muming and Duan Shumin from the Institute of Neuroscience, Shanghai Academy of Biological Sciences, Chinese Academy of Sciences, and their student Song Yuanhong.
Neuronal cells in the brain can divide into two parts: cell bodies, dendrites and axons. The enlarged cell bodies and stubby dendrites are mainly responsible for sensing external information. The long axons, like a highway extending in all directions, are responsible for quickly transmitting information to other relevant nerve cells.
molecular sieve is placed at the junction of cell body dendrites and axons. This checkpoint method of verifying "identity" is very special. It does not directly check the "identity card" of the protein, but waits for the protein to pass through like a rabbit. Don't underestimate this website. If you don't have a certain "horsepower", don't think about passing it-"Small-displacement vehicles are prohibited from being elevated." As a result, protein "information couriers" have to find the "taxi" in nerve cells-motor molecules. However, in the neuron world, motor molecules are regarded as "customers". Only specific proteins can catch motor molecules with enough horsepower to smoothly open the mesh, traverse the molecular sieve, and drive on the axon "highway". In this way, various proteins have embarked on their respective paths.
The paper’s lead author and doctoral student Song Yuanhong told reporters that the results of this research removed the "smart" halo of motor proteins. The discovery of molecular sieves confirmed that motor molecules cannot recognize the difference between axon protein molecules and cell body dendritic protein molecules. When carrying a specific motor molecule between the axon and the cell body dendrites, it is the molecular sieve that plays the final recognition role.