UNASSIGNED: The epithelial @entity1372 channel ( @entity28919 ) has an important role in regulating extracellular fluid volume and blood pressure, as well as airway surface liquid volume and mucociliary clearance. @entity28919 is a trimer of three homologous subunits (a, b and y). We previously reported that cytoplasmic residues on the b (bCys43 and b @entity2569 557) and y (yCys33 and yCys41) subunits are palmitoylated. Mutation of @entity2569 that blocked @entity28919 palmitoylation also reduced channel open probability. Furthermore, y subunit palmitoylation had a dominant role over b subunit palmitoylation in regulating @entity28919 . To determine which palmitoyltransferases (termed DHHCs) regulate the channel, @entity19 ENaCs were co-expressed in Xenopus oocytes with each of the 23 @entity19 DHHCs. @entity28919 activity was significantly increased by @entity69111 . @entity28919 activation by DHHCs was lost when y subunit palmitoylation sites were mutated, while DHHCs 1, 2 and 14 still activated @entity28919 lacking b subunit palmitoylation sites. b subunit palmitoylation was increased by @entity28919 co-expression with @entity69112 . Both wild type @entity28919 and channels lacking b and y palmitoylation sites co-immunoprecipitated with the five activating DHHCs, suggesting that @entity28919 forms a complex with multiple DHHCs. RT-PCR revealed that transcripts for the five activating DHHCs were present in cultured mCCDcl1 cells, and @entity69113 was expressed in aquaporin 2-positive principal cells of @entity19 @entity1369 -sensitive distal nephron where @entity28919 is localized. Treatment of polarized mCCDcl1 cells with a general inhibitor of palmitoylation reduced @entity28919 -mediated @entity4024 currents within minutes. Our results indicate that specific DHHCs have a role in regulating @entity28919 .

Specific Palmitoyltransferases Associate With and Activate the Epithelial XXXX Channel.

@entity69112 :: ('102193(Tax:10090)', 'Gene') :: ['DHHC 7'] @entity69111 :: ('71164;238331', 'Gene') :: ['DHHCs 1, 2, 3, 7 and 14'] @entity1369 :: ('MESH:D000450', 'Chemical') :: ['aldosterone'] @entity4024 :: ('D012964', 'Chemical') :: ['Na(+)'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity2569 :: ('CHEBI:17561', 'Chemical') :: ['Cys'] @entity1372 :: ('MESH:D012964', 'Chemical') :: ['sodium'] @entity69113 :: ('69035(Tax:10090)', 'Gene') :: ['DHHC 3'] @entity28919 :: ('20276(Tax:10090)', 'Gene') :: ['ENaC']
@entity1372 :: (MESH:D012964,Chemical) :: ['Sodium']
