Introducing the brain: a new synapse control (Introduction)

by David Turell , Wednesday, December 07, 2022, 16:57 (500 days ago) @ David Turell

Recent biochemical research:

https://www.the-scientist.com/the-literature/a-novel-player-at-the-neuromuscular-juncti...

"In vertebrates, this signaling happens at the neuromus-cular junction (NMJ), a synaptic connection between motor neurons and muscle fibers. Once stimulated, a neuron will release the neurotransmitter acetylcholine, which then traverses the synapse to bind specialized receptors on the surface of the muscle, triggering a contraction.

A suite of molecular machinery is required for the development and maintenance of the NMJ, which can otherwise become disorganized over time. One well-known player is muscle-specific kinase (MuSK), which forms a complex involved in cell signaling. Recent research has also implicated the Wnt family of proteins, peptides involved in multiple developmental pathways in animals.

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"Strochlic’s group previously reported that Vangl2, a transmembrane protein found on both the neuron and muscle sides of the NMJ, interacts with certain Wnt
proteins—and that mice with mutated Vangl2 have NMJ defects. For their latest project, Strochlic, PhD student Myriam Boëx, and colleagues created location-
specific mouse knockouts, disrupting Vangl2 function either in the motor neuron or in skeletal muscle. Knocking out the protein in the neuron had little effect on NMJ architecture, the team found. But disrupting Vangl2 in the muscle resulted in mice with structurally disorganized junctions, reduced synaptic transmission, and weakness in their diaphragm or leg muscles.

"In vitro biochemical and genetics assays suggested that Vangl2 directly binds to MuSK and mediates Wnt-induced MuSK signaling, Strochlic adds. Although the precise details of the interactions aren’t yet clear, the findings point to Vangl2 being an important component of the complex that helps develop and maintain the NMJ, she says."

Comment: what is required is a complex orchestra of specialized function proteins. In a creative mode, one must think of inventing each protein and setting them up to work together. Logically, this cannot have happened naturally. A designer is required.