Genetic mutation of the class-3 semaphorin receptor component Npn-2 does not enhance rubrospinal tract regeneration
نویسندگان
چکیده
After spinal cord injury, axon outgrowth inhibitors present in myelin and in the neural scar are considered to contribute to the failure of injured axons to re-establish functional connections. Class-3 semaphorins are expressed by the meningeal cells that infiltrate the glial scar after injury and signal by binding to neuropilin-1 (Npn-1) or neuropilin-2 (Npn-2). Since neurons of the red nucleus express only Npn-2, rubrospinal axons of Npn-2 knock out (KO) animals should be insensitive to all class 3 semaphorins. To examine the effect of genetic deletion of Npn-2 on the inability of rubrospinal tract (RST) axons to regenerate, we have analysed RST regeneration in Npn-2 KO and wild type littermates. In this study we report that Npn-2 deficient mice do not exhibit improved RST axon outgrowth and do not show enhanced recovery of motor function.
منابع مشابه
Genetic mutation of the semaphorin 3A receptor component neuropilin-1 in neurons does not enhance corticospinal tract regeneration
After a spinal cord lesion, a myriad of axon growth inhibitors present in myelin and in the neural scar contribute to the failure of injured axons to regenerate. Class 3 semaphorins are repulsive axon guidance cues that are induced in the meningeal fibroblasts that infiltrate the neural scar. Most if not all injured spinal cord neurons, including neurons that form the corticospinal tract (CST),...
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