SFTPA1

Function

In presence of calcium ions, it binds to surfactant phospholipids and contributes to lower the surface tension at the air-liquid interface in the alveoli of the mammalian lung and is essential for normal respiration. Enhances the expression of MYO18A/SP-R210 on alveolar macrophages (By similarity).

(Microbial infection) Recognition of M.tuberculosis by dendritic cells may occur partially via this molecule (PubMed:17158455, PubMed:21203928). Can recognize, bind, and opsonize pathogens to enhance their elimination by alveolar macrophages (PubMed:21123169).

(Microbial infection) Binds M.pneumoniae CARDS toxin, serves as one receptor for this pathogen (PubMed:15845487, PubMed:25139904). When SFTPA1 is down-regulated by siRNA, less toxin binds to human cells and less vacuolization (a symptom of M.pneumoniae infection) is seen (PubMed:25139904).

Involvement in disease

Interstitial lung disease 1

ILD1

A form of interstitial lung disease, a heterogeneous group of diseases affecting the distal part of the lung and characterized by a progressive remodeling of the alveolar interstitium. The disease spectrum ranges from idiopathic interstitial pneumonia or pneumonitis to idiopathic pulmonary fibrosis, that is associated with an increased risk of developing lung cancer. Clinical features of interstitial lung disease include dyspnea, clubbing of the fingers, and restrictive lung capacity. ILD1 inheritance can be autosomal dominant with incomplete penetrance, and autosomal recessive.

None

The disease is caused by variants affecting the gene represented in this entry.

Respiratory distress syndrome in premature infants

RDS

A 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'.

None

Disease susceptibility may be associated with variants affecting the gene represented in this entry. The association between SFTPA1 alleles and respiratory distress syndrome in premature infants is dependent on a variation Ile to Thr at position 131 in SFTPB.

Post-translational modifications

N-acetylated.

Sequence Similarities

Belongs to the SFTPA family.

Cellular localization

• Secreted
• Secreted
• Extracellular space
• Extracellular matrix
• Secreted
• Extracellular space
• Surface film

Alternative names

COLEC4, PSAP, SFTP1, SFTPA, SFTPA1B, SFTPA1, Pulmonary surfactant-associated protein A1, PSP-A, PSPA, SP-A, SP-A1, 35 kDa pulmonary surfactant-associated protein, Alveolar proteinosis protein, Collectin-4

Database links

swissprot:Q8IWL2 entrezGene:6435 swissprot:Q8IWL1 omim:178642 omim:178630 entrezGene:6436 entrezGene:653509 entrezGene:729238