UniProtKB/Swiss-Prot P51168: Variant p.Glu539Lys

Amiloride-sensitive sodium channel subunit beta
Gene: SCNN1B
Chromosomal location: 16p12.1-p12.2
Variant information

Variant position:  539
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  Disease [Disclaimer]
The variants are classified into three categories: Disease, Polymorphism and Unclassified.
  • Disease: Variants have been found in patients and disease-association is reported in literature. However, this classification is not a definitive assessment of variant pathogenicity.
  • Polymorphism: No disease-association has been reported.
  • Unclassified: Variants have been found in patients but disease-association remains unclear.

Residue change:  From Glutamate (E) to Lysine (K) at position 539 (E539K, p.Glu539Lys).
Indicates the amino acid change of the variant. The one-letter and three-letter codes for amino acids used in UniProtKB/Swiss-Prot are those adopted by the commission on Biochemical Nomenclature of the IUPAC-IUB.

Physico-chemical properties:  Change from medium size and acidic (E) to large size and basic (K)
The physico-chemical property of the reference and variant residues and the change implicated.

BLOSUM score:  1
The score within a Blosum matrix for the corresponding wild-type to variant amino acid change. The log-odds score measures the logarithm for the ratio of the likelihood of two amino acids appearing by chance. The Blosum62 substitution matrix is used. This substitution matrix contains scores for all possible exchanges of one amino acid with another:
  • Lowest score: -4 (low probability of substitution).
  • Highest score: 11 (high probability of substitution).
More information can be found on the following page

Involvement in disease:  Bronchiectasis with or without elevated sweat chloride 1 (BESC1) [MIM:211400]: A debilitating respiratory disease characterized by chronic, abnormal dilatation of the bronchi and other cystic fibrosis-like symptoms in the absence of known causes of bronchiectasis (cystic fibrosis, autoimmune diseases, ciliary dyskinesia, common variable immunodeficiency, foreign body obstruction). Clinical features include sub-normal lung function, sinopulmonary infections, chronic productive cough, excessive sputum production, and elevated sweat chloride in some cases. Note=The disease is caused by mutations affecting the gene represented in this entry.
The name and a short description of the disease associated with the variant. For more information about the disease, the user can refer to OMIM, following the link provided after the disease acronym.

Variant description:  In BESC1; decreased channel activity.
Any additional useful information about the variant.



Sequence information

Variant position:  539
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  640
The length of the canonical sequence.

Location on the sequence:   LSNLGGQFGFWMGGSVLCLI  E FGEIIIDFVWITIIKLVALA
The residue change on the sequence. Unless the variant is located at the beginning or at the end of the protein sequence, both residues upstream (20) and downstream (20) of the variant will be shown.

Residue conservation: 
The multiple alignment of the region surrounding the variant against various orthologous sequences.

Human                         LSNLGGQFGFWMGGSVLCLIEFGEIIIDFVWITIIKLVALA

Mouse                         LSNLGGQFGFWMGGSVLCLIEFGEIIIDFIWITIIKLVASC

Rat                           LSNLGGQFGFWMGGSVLCLIEFGEIIIDFIWITVIKLVASC

Rabbit                        LSNLGGQFGFWMGGSVLCLIEFAEIIIDFVWITIIKLVALA

Xenopus laevis                LSNLGGQFGFWMGGSVLCIIEFGEIIIDCMWITILKFLAWS

Sequence annotation in neighborhood:  
The regions or sites of interest surrounding the variant. In general the features listed are posttranslational modifications, binding sites, enzyme active sites, local secondary structure or other characteristics reported in the cited references. The "Sequence annotation in neighborhood" lines have a fixed format:
  • Type: the type of sequence feature.
  • Positions: endpoints of the sequence feature.
  • Description: contains additional information about the feature.

TypePositionsDescription
Chain 1 – 640 Amiloride-sensitive sodium channel subunit beta
Transmembrane 515 – 545 Helical;


Literature citations

Mutations in the beta-subunit of the epithelial Na+ channel in patients with a cystic fibrosis-like syndrome.
Sheridan M.B.; Fong P.; Groman J.D.; Conrad C.; Flume P.; Diaz R.; Harris C.; Knowles M.; Cutting G.R.;
Hum. Mol. Genet. 14:3493-3498(2005)
Cited for: VARIANTS BESC1 CYS-82; LEU-267; SER-294 AND LYS-539; CHARACTERIZATION OF VARIANTS BESC1 LEU-267; SER-294 AND LYS-539;

Disclaimer: Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. They are not in any way intended to be used as a substitute for professional medical advice, diagnostic, treatment or care.