摘要

A Xenopus oocyte heterologous expression system was used to characterise iron transport properties of two members of the solute carrier 11 (sic11) protein family isolated from rainbow trout gills. One cDNA clone differed from the trout Slc11 alpha containing an additional 52 bp in the exon between transmembrane domains (TM) 10 and 11. The 52 bp contained a stop codon, resulting in a novel isoform lacking the last two TM (termed slc11 gamma). Sle11 gamma and another isoform slc11 beta, import Fe2+ at external pHs <= to 7.4. Trout sic11 beta Fe2+ import was more sensitive to inhibition by divalent metals. The novel vertebrate slc11 gamma isoform functions without TM11 and 12.