ID   SFTPA_HORSE             Reviewed;         248 AA.
AC   Q95L88; Q9N0G1;
DT   01-MAR-2005, integrated into UniProtKB/Swiss-Prot.
DT   01-DEC-2001, sequence version 1.
DT   03-AUG-2022, entry version 105.
DE   RecName: Full=Pulmonary surfactant-associated protein A;
DE            Short=PSAP;
DE            Short=PSP-A;
DE            Short=SP-A;
DE   Flags: Precursor;
GN   Name=SFTPA1;
OS   Equus caballus (Horse).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Laurasiatheria; Perissodactyla; Equidae; Equus.
OX   NCBI_TaxID=9796;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   STRAIN=Thoroughbred; TISSUE=Lung;
RA   Hobo S.;
RT   "Molecular cloning of equine pulmonary surfactant proteins.";
RL   Submitted (JUL-1998) to the EMBL/GenBank/DDBJ databases.
RN   [2]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RA   Weber B.I.L., Hospes R., Gortner L.;
RL   Submitted (JUL-2001) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: In presence of calcium ions, it binds to surfactant
CC       phospholipids and contributes to lower the surface tension at the air-
CC       liquid interface in the alveoli of the mammalian lung and is essential
CC       for normal respiration. Enhances the expression of MYO18A/SP-R210 on
CC       alveolar macrophages. {ECO:0000250|UniProtKB:P35242}.
CC   -!- SUBUNIT: Oligomeric complex of 6 set of homotrimers.
CC       {ECO:0000250|UniProtKB:Q8IWL2}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:Q8IWL2}.
CC       Secreted, extracellular space, extracellular matrix
CC       {ECO:0000250|UniProtKB:Q8IWL2}. Secreted, extracellular space, surface
CC       film {ECO:0000250|UniProtKB:Q8IWL2}.
CC   -!- SIMILARITY: Belongs to the SFTPA family. {ECO:0000305}.
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DR   EMBL; AB015963; BAA97976.1; -; mRNA.
DR   EMBL; AF400580; AAL07690.1; -; Genomic_DNA.
DR   RefSeq; NP_001075281.1; NM_001081812.2.
DR   AlphaFoldDB; Q95L88; -.
DR   SMR; Q95L88; -.
DR   STRING; 9796.ENSECAP00000016397; -.
DR   PaxDb; Q95L88; -.
DR   PRIDE; Q95L88; -.
DR   GeneID; 100033826; -.
DR   KEGG; ecb:100033826; -.
DR   CTD; 653509; -.
DR   InParanoid; Q95L88; -.
DR   OrthoDB; 1172460at2759; -.
DR   Proteomes; UP000002281; Unplaced.
DR   GO; GO:0005581; C:collagen trimer; IEA:UniProtKB-KW.
DR   GO; GO:0005615; C:extracellular space; IEA:UniProtKB-SubCell.
DR   GO; GO:0030246; F:carbohydrate binding; IEA:UniProtKB-KW.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   GO; GO:0007585; P:respiratory gaseous exchange by respiratory system; IEA:UniProtKB-KW.
DR   CDD; cd03591; CLECT_collectin_like; 1.
DR   Gene3D; 3.10.100.10; -; 1.
DR   InterPro; IPR001304; C-type_lectin-like.
DR   InterPro; IPR016186; C-type_lectin-like/link_sf.
DR   InterPro; IPR018378; C-type_lectin_CS.
DR   InterPro; IPR033990; Collectin_CTLD.
DR   InterPro; IPR016187; CTDL_fold.
DR   Pfam; PF00059; Lectin_C; 1.
DR   SMART; SM00034; CLECT; 1.
DR   SUPFAM; SSF56436; SSF56436; 1.
DR   PROSITE; PS00615; C_TYPE_LECTIN_1; 1.
DR   PROSITE; PS50041; C_TYPE_LECTIN_2; 1.
PE   2: Evidence at transcript level;
KW   Calcium; Collagen; Disulfide bond; Extracellular matrix; Gaseous exchange;
KW   Glycoprotein; Lectin; Metal-binding; Reference proteome; Secreted; Signal;
KW   Surface film.
FT   SIGNAL          1..20
FT                   /evidence="ECO:0000255"
FT   CHAIN           21..248
FT                   /note="Pulmonary surfactant-associated protein A"
FT                   /id="PRO_0000017456"
FT   DOMAIN          31..100
FT                   /note="Collagen-like"
FT   DOMAIN          134..247
FT                   /note="C-type lectin"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00040"
FT   REGION          34..105
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   BINDING         215
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000250"
FT   BINDING         217
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000250"
FT   BINDING         234
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000250"
FT   BINDING         235
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000250"
FT   CARBOHYD        207
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   DISULFID        26
FT                   /note="Interchain"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00040"
FT   DISULFID        155..246
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00040"
FT   DISULFID        224..238
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00040"
FT   CONFLICT        128
FT                   /note="Q -> L (in Ref. 1; BAA97976)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        131
FT                   /note="M -> V (in Ref. 1; BAA97976)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   248 AA;  26047 MW;  B71133E005C9A5C1 CRC64;
     MLLCSLTLTL ILLAVSGTKC DVKEFCAACS GVPGIPGSPG LPGRDGRDGV KGDPGPPGPI
     GPPGGMPGSP GHDGLIGPPG PPGERGDKGE PGERGPPGPP AYPDEELQTT LHDIRHQILQ
     LMGALSLQGS MLAVGEKVFS TNGQVVDFDA IRESCARAGG RIAVPKSLEE NAAIASLVTK
     HNTYAYLGLE EGPTAGDFYY LDGAPVNYTN WYPGEPRGRG KEKCVEMYTD GQWNDRSCLQ
     YRLAICEF