Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Entry version 114 (03 Jul 2019)
Sequence version 1 (01 Aug 1990)
Previous versions | rss
Help videoAdd a publicationFeedback
Protein

Pulmonary surfactant-associated protein B

Gene

SFTPB

Organism
Canis lupus familiaris (Dog) (Canis familiaris)
Status
Reviewed-Annotation score:

Annotation score:4 out of 5

<p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
-Experimental evidence at protein leveli <p>This indicates the type of evidence that supports the existence of the protein. Note that the ‘protein existence’ evidence does not give information on the accuracy or correctness of the sequence(s) displayed.<p><a href='/help/protein_existence' target='_top'>More...</a></p>

<p>This section provides any useful information about the protein, mostly biological knowledge.<p><a href='/help/function_section' target='_top'>More...</a></p>Functioni

Pulmonary surfactant-associated proteins promote alveolar stability by lowering the surface tension at the air-liquid interface in the peripheral air spaces. SP-B increases the collapse pressure of palmitic acid to nearly 70 millinewtons per meter.

Miscellaneous

Pulmonary surfactant consists of 90% lipid and 10% protein. There are 4 surfactant-associated proteins: 2 collagenous, carbohydrate-binding glycoproteins (SP-A and SP-D) and 2 small hydrophobic proteins (SP-B and SP-C).

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:<p><a href='/help/gene_ontology' target='_top'>More...</a></p>GO - Biological processi

<p>UniProtKB Keywords constitute a <a href="http://www.uniprot.org/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='/help/keywords' target='_top'>More...</a></p>Keywordsi

Biological processGaseous exchange

<p>This section provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.<p><a href='/help/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyi

<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides an exhaustive list of all names of the protein, from commonly used to obsolete, to allow unambiguous identification of a protein.<p><a href='/help/protein_names' target='_top'>More...</a></p>Protein namesi
Recommended name:
Pulmonary surfactant-associated protein B
Short name:
SP-B
Alternative name(s):
6 kDa protein
Pulmonary surfactant protein 18
Short name:
SP 18
Pulmonary surfactant-associated proteolipid SPL(Phe)
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section indicates the name(s) of the gene(s) that code for the protein sequence(s) described in the entry. Four distinct tokens exist: ‘Name’, ‘Synonyms’, ‘Ordered locus names’ and ‘ORF names’.<p><a href='/help/gene_name' target='_top'>More...</a></p>Gene namesi
Name:SFTPB
Synonyms:SFTP3
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides information on the name(s) of the organism that is the source of the protein sequence.<p><a href='/help/organism-name' target='_top'>More...</a></p>OrganismiCanis lupus familiaris (Dog) (Canis familiaris)
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section shows the unique identifier assigned by the NCBI to the source organism of the protein. This is known as the ‘taxonomic identifier’ or ‘taxid’.<p><a href='/help/taxonomic_identifier' target='_top'>More...</a></p>Taxonomic identifieri9615 [NCBI]
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section contains the taxonomic hierarchical classification lineage of the source organism. It lists the nodes as they appear top-down in the taxonomic tree, with the more general grouping listed first.<p><a href='/help/taxonomic_lineage' target='_top'>More...</a></p>Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaLaurasiatheriaCarnivoraCaniformiaCanidaeCanis
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section is present for entries that are part of a <a href="http://www.uniprot.org/proteomes">proteome</a>, i.e. of a set of proteins thought to be expressed by organisms whose genomes have been completely sequenced.<p><a href='/help/proteomes_manual' target='_top'>More...</a></p>Proteomesi
  • UP000002254 <p>A UniProt <a href="http://www.uniprot.org/manual/proteomes_manual">proteome</a> can consist of several components. <br></br>The component name refers to the genomic component encoding a set of proteins.<p><a href='/help/proteome_component' target='_top'>More...</a></p> Componenti: Unplaced

<p>This section provides information on the location and the topology of the mature protein in the cell.<p><a href='/help/subcellular_location_section' target='_top'>More...</a></p>Subcellular locationi

Extracellular region or secreted Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi apparatus Nucleus Mitochondrion Manual annotation Automatic computational assertionGraphics by Christian Stolte & Seán O’Donoghue; Source: COMPARTMENTS

Keywords - Cellular componenti

Secreted, Surface film

<p>This section describes post-translational modifications (PTMs) and/or processing events.<p><a href='/help/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the ‘PTM / Processing’ section denotes the presence of an N-terminal signal peptide.<p><a href='/help/signal' target='_top'>More...</a></p>Signal peptidei‹1 – 16Sequence analysisAdd BLAST›16
<p>This subsection of the <a href="http://www.uniprot.org/help/ptm_processing_section">PTM / Processing</a> section describes a propeptide, which is a part of a protein that is cleaved during maturation or activation. Once cleaved, a propeptide generally has no independent biological function.<p><a href='/help/propep' target='_top'>More...</a></p>PropeptideiPRO_000003164417 – 180Add BLAST164
<p>This subsection of the ‘PTM / Processing’ section describes the extent of a polypeptide chain in the mature protein following processing.<p><a href='/help/chain' target='_top'>More...</a></p>ChainiPRO_0000031645181 – 259Pulmonary surfactant-associated protein BAdd BLAST79
PropeptideiPRO_0000031646260 – 363Add BLAST104

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the PTM / Processing":/help/ptm_processing_section section describes the positions of cysteine residues participating in disulfide bonds.<p><a href='/help/disulfid' target='_top'>More...</a></p>Disulfide bondi62 ↔ 136PROSITE-ProRule annotation
Disulfide bondi65 ↔ 130PROSITE-ProRule annotation
Disulfide bondi93 ↔ 105PROSITE-ProRule annotation
Disulfide bondi188 ↔ 257PROSITE-ProRule annotation
Disulfide bondi191 ↔ 251PROSITE-ProRule annotation
Disulfide bondi215 ↔ 226PROSITE-ProRule annotation
Disulfide bondi228InterchainPROSITE-ProRule annotation
Disulfide bondi281 ↔ 348PROSITE-ProRule annotation
Disulfide bondi284 ↔ 342PROSITE-ProRule annotation
<p>This subsection of the <a href="http://www.uniprot.org/help/ptm_processing_section">PTM / Processing</a> section specifies the position and type of each covalently attached glycan group (mono-, di-, or polysaccharide).<p><a href='/help/carbohyd' target='_top'>More...</a></p>Glycosylationi293N-linked (GlcNAc...) asparaginePROSITE-ProRule annotation1
Disulfide bondi307 ↔ 317PROSITE-ProRule annotation

Keywords - PTMi

Disulfide bond, Glycoprotein

<p>This section provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.<p><a href='/help/interaction_section' target='_top'>More...</a></p>Interactioni

<p>This subsection of the <a href="http://www.uniprot.org/help/interaction_section">'Interaction'</a> section provides information about the protein quaternary structure and interaction(s) with other proteins or protein complexes (with the exception of physiological receptor-ligand interactions which are annotated in the <a href="http://www.uniprot.org/help/function_section">'Function'</a> section).<p><a href='/help/subunit_structure' target='_top'>More...</a></p>Subunit structurei

Homodimer; disulfide-linked.

<p>This section provides information on the tertiary and secondary structure of a protein.<p><a href='/help/structure_section' target='_top'>More...</a></p>Structurei

3D structure databases

SWISS-MODEL Repository - a database of annotated 3D protein structure models

More...
SMRi
P17129

Database of comparative protein structure models

More...
ModBasei
Search...

<p>This section provides information on sequence similarities with other proteins and the domain(s) present in a protein.<p><a href='/help/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the <a href="http://www.uniprot.org/help/family_and_domains_section">Family and Domains</a> section describes the position and type of a domain, which is defined as a specific combination of secondary structures organized into a characteristic three-dimensional structure or fold.<p><a href='/help/domain' target='_top'>More...</a></p>Domaini18 – 58Saposin A-typePROSITE-ProRule annotationAdd BLAST41
Domaini58 – 140Saposin B-type 1PROSITE-ProRule annotationAdd BLAST83
Domaini184 – 261Saposin B-type 2PROSITE-ProRule annotationAdd BLAST78
Domaini277 – 352Saposin B-type 3PROSITE-ProRule annotationAdd BLAST76

Keywords - Domaini

Repeat, Signal

Phylogenomic databases

InParanoid: Eukaryotic Ortholog Groups

More...
InParanoidi
P17129

Family and domain databases

Integrated resource of protein families, domains and functional sites

More...
InterProi
View protein in InterPro
IPR003119 SAP_A
IPR007856 SapB_1
IPR008138 SapB_2
IPR011001 Saposin-like
IPR008139 SaposinB_dom

Pfam protein domain database

More...
Pfami
View protein in Pfam
PF02199 SapA, 1 hit
PF05184 SapB_1, 1 hit
PF03489 SapB_2, 2 hits

Simple Modular Architecture Research Tool; a protein domain database

More...
SMARTi
View protein in SMART
SM00162 SAPA, 1 hit
SM00741 SapB, 3 hits

Superfamily database of structural and functional annotation

More...
SUPFAMi
SSF47862 SSF47862, 3 hits

PROSITE; a protein domain and family database

More...
PROSITEi
View protein in PROSITE
PS51110 SAP_A, 1 hit
PS50015 SAP_B, 3 hits

<p>This section displays by default the canonical protein sequence and upon request all isoforms described in the entry. It also includes information pertinent to the sequence(s), including <a href="http://www.uniprot.org/help/sequence_length">length</a> and <a href="http://www.uniprot.org/help/sequences">molecular weight</a>. The information is filed in different subsections. The current subsections and their content are listed below:<p><a href='/help/sequences_section' target='_top'>More...</a></p>Sequencei

<p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is complete or not.<p><a href='/help/sequence_status' target='_top'>More...</a></p>Sequence statusi: Fragment.

<p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is in its mature form or if it represents the precursor.<p><a href='/help/sequence_processing' target='_top'>More...</a></p>Sequence processingi: The displayed sequence is further processed into a mature form.

P17129-1 [UniParc]FASTAAdd to basket
« Hide
        10         20         30         40         50
LLWLLLLPTL CGLGAADWSA PSLACARGPA FWCQSLEQAL QCRALGHCLQ
60 70 80 90 100
EVWGNARADD LCQECQDIVR ILTKMTKEAI FQDMVRKFLE HECDVLPLKL
110 120 130 140 150
LTPQCHHMLG TYFPVVVDYF QSQINPKIIC KHLGLCKPGL PEPEQESELS
160 170 180 190 200
DPLLDKLILP ELPGALQVTG PHTQDLSEQQ LPIPLPYCWL CRTLIKRIQA
210 220 230 240 250
MIPKGVLAVT VGQVCHVVPL VVGGICQCLG ERYTVLLLDA LLGRMLPQLV
260 270 280 290 300
CGLVLRCSHE DSAGPALASL PSEWSPQESK CQLCMFVTTQ AGNHSEQATP
310 320 330 340 350
QAIRQACLSS WLDRQKCEQF VEQHMPRLQT LASGGRDAHT TCQALGACRT
360
TFSPLQCIHI PHF
Length:363
Mass (Da):40,180
Last modified:August 1, 1990 - v1
<p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.</p> <p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.</p> <p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).</p> <p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x<sup>64</sup> + x<sup>4</sup> + x<sup>3</sup> + x + 1. The algorithm is described in the ISO 3309 standard. </p> <p class="publication">Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.<br /> <strong>Cyclic redundancy and other checksums</strong><br /> <a href="http://www.nrbook.com/b/bookcpdf.php">Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993)</a>)</p> Checksum:iF4DAD0E02D8B2719
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the ‘Sequence’ section is used for sequence fragments to indicate that the residue at the extremity of the sequence is not the actual terminal residue in the complete protein sequence.<p><a href='/help/non_ter' target='_top'>More...</a></p>Non-terminal residuei11

Sequence databases

Select the link destinations:

EMBL nucleotide sequence database

More...
EMBLi

GenBank nucleotide sequence database

More...
GenBanki

DNA Data Bank of Japan; a nucleotide sequence database

More...
DDBJi
Links Updated
M15170 mRNA Translation: AAA30893.1

Protein sequence database of the Protein Information Resource

More...
PIRi
B29072 A29072

<p>This section provides links to proteins that are similar to the protein sequence(s) described in this entry at different levels of sequence identity thresholds (100%, 90% and 50%) based on their membership in UniProt Reference Clusters (<a href="http://www.uniprot.org/help/uniref">UniRef</a>).<p><a href='/help/similar_proteins_section' target='_top'>More...</a></p>Similar proteinsi

<p>This section is used to point to information related to entries and found in data collections other than UniProtKB.<p><a href='/help/cross_references_section' target='_top'>More...</a></p>Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M15170 mRNA Translation: AAA30893.1
PIRiB29072 A29072

3D structure databases

SMRiP17129
ModBaseiSearch...

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Phylogenomic databases

InParanoidiP17129

Family and domain databases

InterProiView protein in InterPro
IPR003119 SAP_A
IPR007856 SapB_1
IPR008138 SapB_2
IPR011001 Saposin-like
IPR008139 SaposinB_dom
PfamiView protein in Pfam
PF02199 SapA, 1 hit
PF05184 SapB_1, 1 hit
PF03489 SapB_2, 2 hits
SMARTiView protein in SMART
SM00162 SAPA, 1 hit
SM00741 SapB, 3 hits
SUPFAMiSSF47862 SSF47862, 3 hits
PROSITEiView protein in PROSITE
PS51110 SAP_A, 1 hit
PS50015 SAP_B, 3 hits

ProtoNet; Automatic hierarchical classification of proteins

More...
ProtoNeti
Search...

MobiDB: a database of protein disorder and mobility annotations

More...
MobiDBi
Search...

<p>This section provides general information on the entry.<p><a href='/help/entry_information_section' target='_top'>More...</a></p>Entry informationi

<p>This subsection of the ‘Entry information’ section provides a mnemonic identifier for a UniProtKB entry, but it is not a stable identifier. Each reviewed entry is assigned a unique entry name upon integration into UniProtKB/Swiss-Prot.<p><a href='/help/entry_name' target='_top'>More...</a></p>Entry nameiPSPB_CANLF
<p>This subsection of the ‘Entry information’ section provides one or more accession number(s). These are stable identifiers and should be used to cite UniProtKB entries. Upon integration into UniProtKB, each entry is assigned a unique accession number, which is called ‘Primary (citable) accession number’.<p><a href='/help/accession_numbers' target='_top'>More...</a></p>AccessioniPrimary (citable) accession number: P17129
<p>This subsection of the ‘Entry information’ section shows the date of integration of the entry into UniProtKB, the date of the last sequence update and the date of the last annotation modification (‘Last modified’). The version number for both the entry and the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> are also displayed.<p><a href='/help/entry_history' target='_top'>More...</a></p>Entry historyiIntegrated into UniProtKB/Swiss-Prot: August 1, 1990
Last sequence update: August 1, 1990
Last modified: July 3, 2019
This is version 114 of the entry and version 1 of the sequence. See complete history.
<p>This subsection of the ‘Entry information’ section indicates whether the entry has been manually annotated and reviewed by UniProtKB curators or not, in other words, if the entry belongs to the Swiss-Prot section of UniProtKB (<strong>reviewed</strong>) or to the computer-annotated TrEMBL section (<strong>unreviewed</strong>).<p><a href='/help/entry_status' target='_top'>More...</a></p>Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

<p>This section contains any relevant information that doesn’t fit in any other defined sections<p><a href='/help/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousi

Keywords - Technical termi

Complete proteome, Direct protein sequencing, Reference proteome
UniProt is an ELIXIR core data resource
Main funding by: National Institutes of Health

We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.

Do not show this banner again