FXYD domain-containing ion transport regulator 1; FXYD domain-containing ion transport regulator 1 (FXYD1), also known as phospholemman (PLM), or sodium/potassium-transporting ATPase subunit FXYD1, associates with and regulates the activity of the sodium/potassium-transporting ATPase (NKA) which transports Na+ out of the cell and K+ into the cell. It is a plasma membrane substrate for several kinases, including protein kinase A, protein kinase C, NIMA kinase, and myotonic dystrophy kinase. It is thought to form an ion channel or regulate ion channel activity. Transcript variants with different 5' UTR sequences have been described in the literature.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1916010  23 PKEHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRCRCKFNQQQRTGEPDEEEGTFRSSIRR 86
Cdd:cd20317  1 PQEHDPFTYDYQSLRIGGLIIAGILFILGILIILSRRCRCKFNQQQRTGEPDEEEGTFRSSIRR 64

FXYD domain-containing ion transport regulator 1; FXYD domain-containing ion transport regulator 1 (FXYD1), also known as phospholemman (PLM), or sodium/potassium-transporting ATPase subunit FXYD1, associates with and regulates the activity of the sodium/potassium-transporting ATPase (NKA) which transports Na+ out of the cell and K+ into the cell. It is a plasma membrane substrate for several kinases, including protein kinase A, protein kinase C, NIMA kinase, and myotonic dystrophy kinase. It is thought to form an ion channel or regulate ion channel activity. Transcript variants with different 5' UTR sequences have been described in the literature.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1916010  23 PKEHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRCRCKFNQQQRTGEPDEEEGTFRSSIRR 86
Cdd:cd20317  1 PQEHDPFTYDYQSLRIGGLIIAGILFILGILIILSRRCRCKFNQQQRTGEPDEEEGTFRSSIRR 64

FXYD domain-containing ion transport regulator 1; FXYD domain-containing ion transport regulator 1 (FXYD1), also known as phospholemman (PLM), or sodium/potassium-transporting ATPase subunit FXYD1, associates with and regulates the activity of the sodium/potassium-transporting ATPase (NKA) which transports Na+ out of the cell and K+ into the cell. It is a plasma membrane substrate for several kinases, including protein kinase A, protein kinase C, NIMA kinase, and myotonic dystrophy kinase. It is thought to form an ion channel or regulate ion channel activity. Transcript variants with different 5' UTR sequences have been described in the literature.

                       10        20        30        40        50        60
               ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1916010  23 PKEHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRCRCKFNQQQRTGEPDEEEGTFRSSIRR 86
Cdd:cd20317  1 PQEHDPFTYDYQSLRIGGLIIAGILFILGILIILSRRCRCKFNQQQRTGEPDEEEGTFRSSIRR 64

ATP1G1/PLM/MAT8 family;

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                 ....*....|....*....|....*....|....*....|....*..
gi 1916010    24 KEHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRCRCKFNQQQRT 70
Cdd:pfam02038  1 DEDDPFYYDYETLRIGGLIFAGLLFIVGILIILSKKCKCKFNQKPRS 47

FXYD domain-containing ion transport regulator 4; FXYD domain-containing ion transport regulator 4 (FXYD4), also known as CHIF (channel-inducing factor or corticosteroid hormone-induced factor), evokes K+ conductance in oocytes and is localized in the distal parts of the nephron and in the colon. CHIF, a putative K channel regulator, is regulated by aldosterone in the colon and by K+ intake in the kidney.

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               ....*....|....*....|....*....|....*....|...
gi 1916010  25 EHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRCRCKFNQQ 67
Cdd:cd20322  6 KDSPFYYDWESLQLGGMICAGLLCIAGIAFALSGKCKCKHSQK 48

FXYD domain-containing ion transport regulator 7; FXYD domain-containing ion transport regulator 7 (FXYD7) has a potential splice variant with an additional 3 residues. In rats, expression of FXYD7 was restricted to the brain, with highest levels in the cerebrum, followed by brainstem, and hippocampus, and relatively weak expression in the hypothalamus. Immunofluorescence microscopy demonstrated colocalization with synaptophysin and modest colocalization with glial fibrillary acidic protein, indicating predominant expression in neurons and lower expression in astroglial cells. The FXYD7 gene maps to chromosome 19.

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               ....*....|....*....|....*....|....*....|....*...
gi 1916010  23 PKEHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRCRCKFNQQQRT 70
Cdd:cd20325  1 FEDQSPFEYDYETLRTTGVILAVVMFVLGILIALSKKFKCKKSDSSKS 48

phenylalanine-X-tyrosine-aspartate (FXYD) family; FXYDs are small single-transmembrane proteins that act as novel regulators of Na+/K+-ATPase (NKA). The transmembrane domain and the conserved Phe-X-Tyr-Asp motif of FXYD play a role in the binding of FXYD to the alpha- and beta-subunits of NKA. PFXYD (proline-phenylalanine-X-tyrosine-aspartate) at the beginning of the signature sequence is invariant in all known examples in mammals and identical except for the proline in other vertebrates; X is usually Y (tyrosine), but can also be E, T, or H (glutamate, threonine, or histidine). The FXYD protein family contains at least twelve members that have the extracellular FXYD motif, transmembrane domain, and intracellular domain. Members share a 35-amino acid signature sequence domain, beginning with PFXYD and containing 7 invariant and 6 highly conserved amino acids. In mammals, members of the FXYD family include FXYD1 (phospholemman, PLM), FXYD2 (the gamma-subunit of NKA), FXYD3 (mammary tumor marker Mat-8), FXYD4 (corticosteroid hormone-induced factor, CHIF), FXYD5 (dysadherin), FXYD6 (phosphohippolin), and FXYD7. In elasmobranchs, FXYD10 (phospholemman-like protein from shark, PLMS) was first identified in the rectal glands of Squalus acanthias. In addition, studies on sharks reported that the functions of FXYD10 via its C-terminal cysteine residue interactions were associated with negative regulation of shark NKA activity. Teleostean FXYD proteins (FXYD2, 5-9, 11, and 12) have been reported in certain teleosts such as the Tetraodon nigroviridis, Salmo salar, Danio rerio, and Oryzias dancena. Recent studies have demonstrated that several teleost FXYD isoforms are expressed in the gills and kidneys of the fish, and their expression levels are altered in response to salinity changes, suggesting that these FXYDs may regulate electrolyte homeostasis and body fluid of the fish.

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gi 1916010  29 FTYDYQSLQIGGLVIAGILFILGILIVLSR 58
Cdd:cd20277  1 FYYDYETLRIGGLVFAAVLFIVGILILLSG 30

FXYD domain-containing ion transport regulator 11; FXYD domain-containing ion transport regulator 11 (FXYD11) is a putative regulatory subunit of the Na(+)/K(+)-ATPase (NKA) pump. FXYD11 is expressed predominantly in the gills of euryhaline teleosts, such as the spotted scat, Scatophagus argus. It regulates NKA activity through protein-protein interactions. The regulation of NKA and FXYD11 is of critical importance for osmotic homeostasis. The expression and activity of NKA, as well as FXYD11 mRNA expression in gills have been shown to respond to different environmental salinity by dual-labeling immunohistochemistry and quantitative PCR (RT-qPCR) methods, indicating that there is an interaction between NKA and FXYD.

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               ....*....|....*....|....*....|....*.
gi 1916010  25 EHDPFTYDYQSLQIGGLVIAGILFILGILIVLSRRC 60
Cdd:cd20329 21 EANPFVYNYERLRIGGLVFACLLVAGGISVLLYNKC 56