The iodide transport defect-causing Y348D mutation in the Na < sup > + < /sup > /I < sup > - < /sup > symporter (NIS) renders the protein intrinsically inactive and impairs its targeting to the plasma membrane

CONCLUSIONS: Y348D NIS does not reach the plasma membrane and is intrinsically inactive. Hydrophobic amino acid substitutions at position 348, however, preserve NIS activity. Our findings are consistent with our homology model's prediction that Y348 should face the side opposite the TMS9 residues that coordinate Na+ and participate in Na+ transport, and with the notion that Y348 interacts only with hydrophobic residues. Hydrophilic or charged residues at position 348 have deleterious effects on NIS plasma membrane targeting and activity, whereas a hydrophobic residue at this position rescues NIS activity.PMID:33779310 | DOI:10.1089/thy.2020.0931
Source: Thyroid : official journal of the American Thyroid Association - Category: Endocrinology Authors: Source Type: research