ID   SCNNB_LITCT             Reviewed;         273 AA.
AC   Q9W754;
DT   01-DEC-2000, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1999, sequence version 1.
DT   25-MAY-2022, entry version 87.
DE   RecName: Full=Amiloride-sensitive sodium channel subunit beta;
DE   AltName: Full=Beta-NaCH;
DE   AltName: Full=Epithelial Na(+) channel subunit beta;
DE            Short=Beta-ENaC;
DE   AltName: Full=Nonvoltage-gated sodium channel 1 subunit beta;
DE   AltName: Full=SCNEB;
DE   Flags: Fragment;
GN   Name=SCNN1B;
OS   Lithobates catesbeianus (American bullfrog) (Rana catesbeiana).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC   Batrachia; Anura; Neobatrachia; Ranoidea; Ranidae; Lithobates.
OX   NCBI_TaxID=8400;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Skin;
RA   Al-Khalili O.K., Stockand J.D., Eaton D.C.;
RT   "Rana catesbiana epithelial sodium channel (larval skin): beta subunit.";
RL   Submitted (MAY-1999) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Sodium permeable non-voltage-sensitive ion channel inhibited
CC       by the diuretic amiloride. Mediates the electrodiffusion of the luminal
CC       sodium (and water, which follows osmotically) through the apical
CC       membrane of epithelial cells. Plays an essential role in electrolyte
CC       and blood pressure homeostasis, but also in airway surface liquid
CC       homeostasis, which is important for proper clearance of mucus.
CC       {ECO:0000250|UniProtKB:P51168}.
CC   -!- SUBUNIT: Heterotrimer containing an alpha/SCNN1A, a beta/SCNN1B and a
CC       gamma/SCNN1G subunit. An additional delta/SCNN1D subunit exists only in
CC       some organisms and can replace the alpha/SCNN1A subunit to form an
CC       alternative channel with specific properties.
CC       {ECO:0000250|UniProtKB:P51168}.
CC   -!- SUBCELLULAR LOCATION: Apical cell membrane
CC       {ECO:0000250|UniProtKB:P37090}; Multi-pass membrane protein
CC       {ECO:0000250|UniProtKB:P37089}. Cytoplasmic vesicle membrane
CC       {ECO:0000250|UniProtKB:P37090}. Note=Apical membrane of epithelial
CC       cells. {ECO:0000250|UniProtKB:P37090}.
CC   -!- SIMILARITY: Belongs to the amiloride-sensitive sodium channel (TC
CC       1.A.6) family. SCNN1B subfamily. {ECO:0000305}.
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DR   EMBL; AF153690; AAD40246.1; -; mRNA.
DR   AlphaFoldDB; Q9W754; -.
DR   SMR; Q9W754; -.
DR   GO; GO:0016324; C:apical plasma membrane; ISS:UniProtKB.
DR   GO; GO:0030659; C:cytoplasmic vesicle membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0005887; C:integral component of plasma membrane; ISS:UniProtKB.
DR   GO; GO:0034706; C:sodium channel complex; ISS:UniProtKB.
DR   GO; GO:0015280; F:ligand-gated sodium channel activity; IEA:InterPro.
DR   GO; GO:0050891; P:multicellular organismal water homeostasis; ISS:UniProtKB.
DR   GO; GO:0055078; P:sodium ion homeostasis; ISS:UniProtKB.
DR   GO; GO:0035725; P:sodium ion transmembrane transport; ISS:UniProtKB.
DR   InterPro; IPR001873; ENaC.
DR   InterPro; IPR004724; ENaC_chordates.
DR   InterPro; IPR020903; ENaC_CS.
DR   PANTHER; PTHR11690; PTHR11690; 1.
DR   Pfam; PF00858; ASC; 1.
DR   PRINTS; PR01078; AMINACHANNEL.
DR   TIGRFAMs; TIGR00859; ENaC; 1.
DR   PROSITE; PS01206; ASC; 1.
PE   2: Evidence at transcript level;
KW   Cell membrane; Cytoplasmic vesicle; Ion channel; Ion transport; Membrane;
KW   Sodium; Sodium channel; Sodium transport; Transmembrane;
KW   Transmembrane helix; Transport.
FT   CHAIN           <1..>273
FT                   /note="Amiloride-sensitive sodium channel subunit beta"
FT                   /id="PRO_0000181273"
FT   TOPO_DOM        <1..245
FT                   /note="Extracellular"
FT                   /evidence="ECO:0000250"
FT   TRANSMEM        246..>273
FT                   /note="Helical"
FT                   /evidence="ECO:0000250"
FT   NON_TER         1
FT   NON_TER         273
SQ   SEQUENCE   273 AA;  31214 MW;  CEE57DB051EE5291 CRC64;
     NCYIFNWGQE GQELLESANP GADFGLKMVL DIDQKEYIPF LQSTAAARII LHQQRSFPFL
     KDLGIYAMPG TETSIAVLED QTQHLEAPYS SCTVDGSDIP VANIYSKFNS SYSIQSCLRS
     CFQEIMVKYC KCAYYLFPLL NGAHYCNNQE DPDWVPCYYN IWDTVSHREQ CINMCQQPCN
     DSNYKMTISM ADWPSAAAED WIFHVLSYEK DTSLDITVNR DGIMRLNIYF EEFNYRSISE
     SPTTNVVWLL SNLGGQFGFW MGGSVLCIIE FGE