MEC-10 and MEC-19 Reduce the Neurotoxicity of the MEC-4(d) DEG/ENaC Channel in Caenorhabditis elegans
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چکیده
The Caenorhabditis elegans DEG/ENaC proteins MEC-4 and MEC-10 transduce gentle touch in the six touch receptor neurons . Gain-of-function mutations of mec-4 and mec-4(d) result in a hyperactive channel and neurodegeneration in vivo Loss of MEC-6, a putative DEG/ENaC-specific chaperone, and of the similar protein POML-1 suppresses the neurodegeneration caused by a mec-4(d) mutation. We find that mutation of two genes, mec-10 and a new gene mec-19 (previously named C49G9.1), prevents this action of POML-1, allowing the touch receptor neurons to die in poml-1 mec-4(d) animals. The proteins encoded by these genes normally inhibit mec-4(d) neurotoxicity through different mechanisms. MEC-10, a subunit of the mechanosensory transduction channel with MEC-4, inhibits MEC-4(d) activity without affecting MEC-4 expression. In contrast, MEC-19, a membrane protein specific to nematodes, inhibits MEC-4(d) activity and reduces MEC-4 surface expression.
منابع مشابه
Caenorhabditis elegans paraoxonase-like proteins control the functional expression of DEG/ENaC mechanosensory proteins
Caenorhabditis eleganssenses gentle touch via a mechanotransduction channel formed from the DEG/ENaC proteins MEC-4 and MEC-10. An additional protein, the paraoxonase-like protein MEC-6, is essential for transduction, and previous work suggested that MEC-6 was part of the transduction complex. We found that MEC-6 and a similar protein, POML-1, reside primarily in the endoplasmic reticulum and d...
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