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Protein

Pulmonary surfactant-associated protein B

Gene

SFTPB

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: -Experimental evidence at protein leveli

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).

GO - Biological processi

Keywordsi

Biological processGaseous exchange

Enzyme and pathway databases

ReactomeiR-HSA-5683826 Surfactant metabolism
R-HSA-5688031 Defective pro-SFTPB causes pulmonary surfactant metabolism dysfunction 1 (SMDP1) and respiratory distress syndrome (RDS)
R-HSA-5688354 Defective pro-SFTPC causes pulmonary surfactant metabolism dysfunction 2 (SMDP2) and respiratory distress syndrome (RDS)
R-HSA-5688849 Defective CSF2RB causes pulmonary surfactant metabolism dysfunction 5 (SMDP5)
R-HSA-5688890 Defective CSF2RA causes pulmonary surfactant metabolism dysfunction 4 (SMDP4)
SIGNORiP07988

Names & Taxonomyi

Protein namesi
Recommended name:
Pulmonary surfactant-associated protein B
Short name:
SP-B
Alternative name(s):
18 kDa pulmonary-surfactant protein
6 kDa protein
Pulmonary surfactant-associated proteolipid SPL(Phe)
Gene namesi
Name:SFTPB
Synonyms:SFTP3
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 2

Organism-specific databases

EuPathDBiHostDB:ENSG00000168878.16
HGNCiHGNC:10801 SFTPB
MIMi178640 gene
neXtProtiNX_P07988

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; Source: COMPARTMENTS

Keywords - Cellular componenti

Secreted, Surface film

Pathology & Biotechi

Involvement in diseasei

Pulmonary surfactant metabolism dysfunction 1 (SMDP1)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA rare lung disorder due to impaired surfactant homeostasis. It is characterized by alveolar filling with floccular material that stains positive using the periodic acid-Schiff method and is derived from surfactant phospholipids and protein components. Excessive lipoproteins accumulation in the alveoli results in severe respiratory distress.
See also OMIM:265120
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_036856236R → C in SMDP1. 1 PublicationCorresponds to variant dbSNP:rs137853202Ensembl.1
Respiratory distress syndrome in premature infants (RDS)1 Publication
Disease susceptibility may be associated with variations affecting the gene represented in this entry. A variation Ile to Thr at position 131 influences the association between specific alleles of SFTPA1 and respiratory distress syndrome in premature infants.
Disease descriptionA lung disease affecting usually premature newborn infants. It is characterized by deficient gas exchange, diffuse atelectasis, high-permeability lung edema and fibrin-rich alveolar deposits called 'hyaline membranes'.
See also OMIM:267450

Keywords - Diseasei

Disease mutation

Organism-specific databases

DisGeNETi6439
MalaCardsiSFTPB
MIMi265120 phenotype
267450 phenotype
OpenTargetsiENSG00000168878
Orphaneti70587 Infant acute respiratory distress syndrome
217563 Neonatal acute respiratory distress due to SP-B deficiency
PharmGKBiPA35713

Polymorphism and mutation databases

BioMutaiSFTPB
DMDMi131418

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Signal peptidei1 – 24Sequence analysisAdd BLAST24
PropeptideiPRO_000003164725 – 200Add BLAST176
ChainiPRO_0000031648201 – 279Pulmonary surfactant-associated protein BAdd BLAST79
PropeptideiPRO_0000031649280 – 381Add BLAST102

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Disulfide bondi69 ↔ 143PROSITE-ProRule annotation
Disulfide bondi72 ↔ 137PROSITE-ProRule annotation
Disulfide bondi100 ↔ 112PROSITE-ProRule annotation
Glycosylationi129N-linked (GlcNAc...) asparaginePROSITE-ProRule annotation1
Disulfide bondi208 ↔ 277PROSITE-ProRule annotation1 Publication
Disulfide bondi211 ↔ 271PROSITE-ProRule annotation1 Publication
Disulfide bondi235 ↔ 246PROSITE-ProRule annotation1 Publication
Disulfide bondi248InterchainPROSITE-ProRule annotation1 Publication
Disulfide bondi299 ↔ 366PROSITE-ProRule annotation
Disulfide bondi302 ↔ 360PROSITE-ProRule annotation
Glycosylationi311N-linked (GlcNAc...) asparaginePROSITE-ProRule annotation1
Disulfide bondi325 ↔ 335PROSITE-ProRule annotation

Keywords - PTMi

Disulfide bond, Glycoprotein

Proteomic databases

PaxDbiP07988
PeptideAtlasiP07988
PRIDEiP07988
ProteomicsDBi52054

Miscellaneous databases

PMAP-CutDBiP07988

Expressioni

Gene expression databases

BgeeiENSG00000168878 Expressed in 211 organ(s), highest expression level in visceral pleura
CleanExiHS_SFTPB
ExpressionAtlasiP07988 baseline and differential
GenevisibleiP07988 HS

Organism-specific databases

HPAiCAB002440
HPA034820
HPA062148

Interactioni

Subunit structurei

Homodimer; disulfide-linked.1 Publication

Protein-protein interaction databases

IntActiP07988, 1 interactor
STRINGi9606.ENSP00000377409

Structurei

Secondary structure

1381
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details

3D structure databases

ProteinModelPortaliP07988
SMRiP07988
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP07988

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini25 – 65Saposin A-typePROSITE-ProRule annotationAdd BLAST41
Domaini65 – 147Saposin B-type 1PROSITE-ProRule annotationAdd BLAST83
Domaini204 – 281Saposin B-type 2PROSITE-ProRule annotationAdd BLAST78
Domaini295 – 370Saposin B-type 3PROSITE-ProRule annotationAdd BLAST76

Keywords - Domaini

Repeat, Signal

Phylogenomic databases

eggNOGiKOG1340 Eukaryota
ENOG410XSI5 LUCA
GeneTreeiENSGT00530000063434
HOGENOMiHOG000115745
HOVERGENiHBG006905
InParanoidiP07988
PhylomeDBiP07988

Family and domain databases

InterProiView protein in InterPro
IPR003119 SAP_A
IPR007856 SapB_1
IPR008138 SapB_2
IPR008373 Saposin
IPR011001 Saposin-like
IPR008139 SaposinB_dom
PfamiView protein in Pfam
PF02199 SapA, 1 hit
PF05184 SapB_1, 1 hit
PF03489 SapB_2, 2 hits
PRINTSiPR01797 SAPOSIN
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

Sequence (1+)i

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

This entry has 1 described isoform and 3 potential isoforms that are computationally mapped.Show allAlign All

P07988-1 [UniParc]FASTAAdd to basket
« Hide
        10         20         30         40         50
MAESHLLQWL LLLLPTLCGP GTAAWTTSSL ACAQGPEFWC QSLEQALQCR
60 70 80 90 100
ALGHCLQEVW GHVGADDLCQ ECEDIVHILN KMAKEAIFQD TMRKFLEQEC
110 120 130 140 150
NVLPLKLLMP QCNQVLDDYF PLVIDYFQNQ TDSNGICMHL GLCKSRQPEP
160 170 180 190 200
EQEPGMSDPL PKPLRDPLPD PLLDKLVLPV LPGALQARPG PHTQDLSEQQ
210 220 230 240 250
FPIPLPYCWL CRALIKRIQA MIPKGALAVA VAQVCRVVPL VAGGICQCLA
260 270 280 290 300
ERYSVILLDT LLGRMLPQLV CRLVLRCSMD DSAGPRSPTG EWLPRDSECH
310 320 330 340 350
LCMSVTTQAG NSSEQAIPQA MLQACVGSWL DREKCKQFVE QHTPQLLTLV
360 370 380
PRGWDAHTTC QALGVCGTMS SPLQCIHSPD L
Length:381
Mass (Da):42,117
Last modified:May 1, 1992 - v3
Checksum:i9FD7F66678A35153
GO

Computationally mapped potential isoform sequencesi

There are 3 potential isoforms mapped to this entry.BLASTAlignShow allAdd to basket
EntryEntry nameProtein names
Gene namesLengthAnnotation
D6W5L6D6W5L6_HUMAN
Pulmonary surfactant-associated pro...
SFTPB hCG_34600
393Annotation score:
H0Y7V6H0Y7V6_HUMAN
Pulmonary surfactant-associated pro...
SFTPB
374Annotation score:
U3KQT2U3KQT2_HUMAN
Pulmonary surfactant-associated pro...
SFTPB
92Annotation score:

Sequence cautioni

The sequence AAA88099 differs from that shown. Reason: Erroneous initiation.Curated

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti178L → V in AAA36628 (PubMed:3343343).Curated1
Sequence conflicti318P → L in AAA88099 (PubMed:3035561).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_006948131T → I2 PublicationsCorresponds to variant dbSNP:rs1130866Ensembl.1
Natural variantiVAR_013099176L → F1 PublicationCorresponds to variant dbSNP:rs3024801Ensembl.1
Natural variantiVAR_006950228A → I Requires 2 nucleotide substitutions. 1 Publication1
Natural variantiVAR_006949228A → R Requires 2 nucleotide substitutions. 2 Publications1
Natural variantiVAR_036856236R → C in SMDP1. 1 PublicationCorresponds to variant dbSNP:rs137853202Ensembl.1
Natural variantiVAR_013100272R → H1 PublicationCorresponds to variant dbSNP:rs3024809Ensembl.1

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
J02761 mRNA Translation: AAA60212.1
M24461 Genomic DNA Translation: AAB59541.1
AF400074 Genomic DNA Translation: AAK77913.1
BC032785 mRNA Translation: AAH32785.1
M16764 mRNA Translation: AAA88099.1 Different initiation.
M19097 mRNA Translation: AAA36628.1
PIRiA31361 LNHUB
RefSeqiNP_000533.3, NM_000542.3
NP_942140.2, NM_198843.2
UniGeneiHs.512690

Genome annotation databases

EnsembliENST00000393822; ENSP00000377409; ENSG00000168878
ENST00000519937; ENSP00000428719; ENSG00000168878
GeneIDi6439
KEGGihsa:6439
UCSCiuc061lja.1 human

Keywords - Coding sequence diversityi

Polymorphism

Similar proteinsi

Cross-referencesi

Web resourcesi

SeattleSNPs

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
J02761 mRNA Translation: AAA60212.1
M24461 Genomic DNA Translation: AAB59541.1
AF400074 Genomic DNA Translation: AAK77913.1
BC032785 mRNA Translation: AAH32785.1
M16764 mRNA Translation: AAA88099.1 Different initiation.
M19097 mRNA Translation: AAA36628.1
PIRiA31361 LNHUB
RefSeqiNP_000533.3, NM_000542.3
NP_942140.2, NM_198843.2
UniGeneiHs.512690

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1DFWinfrared-A201-225[»]
1KMRNMR-A211-225[»]
1RG3NMR-A263-278[»]
1RG4NMR-A263-278[»]
1SSZinfrared-A208-278[»]
2DWFNMR-A208-278[»]
2JOUNMR-A208-278[»]
2M0HNMR-A259-280[»]
2M1TNMR-A259-278[»]
ProteinModelPortaliP07988
SMRiP07988
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

IntActiP07988, 1 interactor
STRINGi9606.ENSP00000377409

Polymorphism and mutation databases

BioMutaiSFTPB
DMDMi131418

Proteomic databases

PaxDbiP07988
PeptideAtlasiP07988
PRIDEiP07988
ProteomicsDBi52054

Protocols and materials databases

DNASUi6439
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000393822; ENSP00000377409; ENSG00000168878
ENST00000519937; ENSP00000428719; ENSG00000168878
GeneIDi6439
KEGGihsa:6439
UCSCiuc061lja.1 human

Organism-specific databases

CTDi6439
DisGeNETi6439
EuPathDBiHostDB:ENSG00000168878.16
GeneCardsiSFTPB
HGNCiHGNC:10801 SFTPB
HPAiCAB002440
HPA034820
HPA062148
MalaCardsiSFTPB
MIMi178640 gene
265120 phenotype
267450 phenotype
neXtProtiNX_P07988
OpenTargetsiENSG00000168878
Orphaneti70587 Infant acute respiratory distress syndrome
217563 Neonatal acute respiratory distress due to SP-B deficiency
PharmGKBiPA35713
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG1340 Eukaryota
ENOG410XSI5 LUCA
GeneTreeiENSGT00530000063434
HOGENOMiHOG000115745
HOVERGENiHBG006905
InParanoidiP07988
PhylomeDBiP07988

Enzyme and pathway databases

ReactomeiR-HSA-5683826 Surfactant metabolism
R-HSA-5688031 Defective pro-SFTPB causes pulmonary surfactant metabolism dysfunction 1 (SMDP1) and respiratory distress syndrome (RDS)
R-HSA-5688354 Defective pro-SFTPC causes pulmonary surfactant metabolism dysfunction 2 (SMDP2) and respiratory distress syndrome (RDS)
R-HSA-5688849 Defective CSF2RB causes pulmonary surfactant metabolism dysfunction 5 (SMDP5)
R-HSA-5688890 Defective CSF2RA causes pulmonary surfactant metabolism dysfunction 4 (SMDP4)
SIGNORiP07988

Miscellaneous databases

ChiTaRSiSFTPB human
EvolutionaryTraceiP07988
GeneWikiiPulmonary_surfactant-associated_protein_B
GenomeRNAii6439
PMAP-CutDBiP07988
PROiPR:P07988
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000168878 Expressed in 211 organ(s), highest expression level in visceral pleura
CleanExiHS_SFTPB
ExpressionAtlasiP07988 baseline and differential
GenevisibleiP07988 HS

Family and domain databases

InterProiView protein in InterPro
IPR003119 SAP_A
IPR007856 SapB_1
IPR008138 SapB_2
IPR008373 Saposin
IPR011001 Saposin-like
IPR008139 SaposinB_dom
PfamiView protein in Pfam
PF02199 SapA, 1 hit
PF05184 SapB_1, 1 hit
PF03489 SapB_2, 2 hits
PRINTSiPR01797 SAPOSIN
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
ProtoNetiSearch...

Entry informationi

Entry nameiPSPB_HUMAN
AccessioniPrimary (citable) accession number: P07988
Secondary accession number(s): Q96R04
Entry historyiIntegrated into UniProtKB/Swiss-Prot: August 1, 1988
Last sequence update: May 1, 1992
Last modified: November 7, 2018
This is version 196 of the entry and version 3 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 2
    Human chromosome 2: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
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Main funding by: National Institutes of Health

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