Restoration of proper trafficking to the cell surface for membrane proteins harboring cysteine mutations.
A common phenotype for many genetic diseases is that the cell is unable to deliver full-length membrane proteins to the cell surface. For some forms of autism, hereditary spherocytosis and color blindness, the culprits are single point mutations to cysteine. We have studied two inheritable cysteine mutants of cyclic nucleotide-gated channels that produce achromatopsia, a common form of severe color blindness. By taking advantage of the reactivity of cysteine's sulfhydryl group, we modified these mutants with chemical reagents that attach moieties with similar chemistries to the wild-type amino acids' side chains. We show that these modifications restored proper delivery to the cell membrane. Once there, the channels exhibited normal functional properties. This strategy might provide a unique opportunity to assess the chemical nature of membrane protein traffic problems.
Neurophysiology Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, Maryland, USA.
Angelica
A
Lopez-Rodriguez
Miguel
M
Holmgren
D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D002417:Cattle; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000235:genetics / Q000378:metabolism; D003545:Cysteine / Q000235:genetics*; D005020:Ethyl Methanesulfonate / Q000031:analogs & derivatives / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D050505:Mutant Proteins / Q000378:metabolism; D009154:Mutation / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013997:Time Factors; D014981:Xenopus
D054815:Cyclic Nucleotide-Gated Cation Channels; D008565:Membrane Proteins; D050505:Mutant Proteins; D011993:Recombinant Fusion Proteins; C093171:methanethiosulfonate ethylammonium; D049452:Green Fluorescent Proteins; D005020:Ethyl Methanesulfonate; D003545:Cysteine