Details for: SFTA2

Gene ID: 389376

Gene Type:  Protein-coding  - A gene that serves as a template for producing a messenger RNA (mRNA) molecule, which is then translated into a functional protein.

Symbol: SFTA2

Ensembl ID: ENSG00000196260

Description: surfactant associated 2

Selected Context(s):  Overall

Cell Significance Landscape

Contexts:

Associated with

Significant Cells

Cell Significance Index (CSI) scores for the chosen context(s)

  • epithelial cell of lung CL0000082
    CSI 7.12
    rCSI 5.9%
    PRS 98.72
  • pulmonary alveolar type 2 cell CL0002063
    CSI 5.96
    rCSI 9.25%
    PRS 98.07
  • kidney loop of Henle thin descending limb epithelial cell CL1001111
    CSI 4.2
    rCSI 5.96%
    PRS 97.64
  • stem cell CL0000034
    CSI 3.04
    rCSI 2.93%
    PRS 97.4
  • ciliated epithelial cell CL0000067
    CSI 2.79
    rCSI 2.45%
    PRS 94.56
  • epithelial cell CL0000066
    CSI 2.7
    rCSI 4.15%
    PRS 92.3
  • lung ciliated cell CL1000271
    CSI 2.66
    rCSI 3.08%
    PRS 95.91
  • kidney loop of Henle thin ascending limb epithelial cell CL1001107
    CSI 2.19
    rCSI 5.67%
    PRS 97.46
  • foveolar cell of stomach CL0002179
    CSI 2
    rCSI 4.25%
    PRS 98.27
  • pancreatic ductal cell CL0002079
    CSI 1.95
    rCSI 3.79%
    PRS 97.99
  • pulmonary alveolar type 1 cell CL0002062
    CSI 1.39
    rCSI 8.02%
    PRS 96.95
  • epithelial cell of esophagus CL0002252
    CSI 0.6
    rCSI 5.89%
    PRS 95.67

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this specific cell.

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this cell type. Calculated using techniques like effect size estimation and bootstrapping for reliability.

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this cell type. Calculated using techniques like effect size estimation and bootstrapping for reliability.
Network Configuration

Explore relationships of the current gene. Select an Interaction Source: 'ONTOLOGY' for shared pathways (GO/Reactome) or 'STRING' for protein-protein interactions. Further refine by selecting context genes and comparing Cell Significance Index (CSI) scores between baseline and target cell types and their specific contexts.

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  • Node Color (Target Cell CSI, relative to current network):
    • Very High
    • High
    • Medium
    • Low
    • Very Low
    • CSI N/A
  • Node Size: Proportional to Target Cell CSI magnitude
  • STRING PPI Edge
  • Shared Pathway Edge (ONTOLOGY)

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Other Information

This section provides additional information about the gene, including a description generated by an AI language model and details about associated proteins.

## Summary [SFTA2](/details-gene/389376) (surfactant associated 2) is a protein-coding gene located on human chromosome 6p21.33. As its name suggests, it encodes a secreted protein that shows a highly specific expression pattern. **Overall**, the expression data strongly indicates that [SFTA2](/details-gene/389376) is a key marker for specialized secretory epithelial cells, particularly within the pulmonary system. Its function is closely tied to the extracellular environment, consistent with its identification as a novel secretory peptide involved in the response to inflammatory stimuli ([Link](https://doi.org/10.1371/journal.pone.0040011)). ## Cellular Roles and Expression Landscape The expression profile of [SFTA2](/details-gene/389376) is characterized by its high significance in a distinct set of epithelial cell types, primarily located in the lung. It is most prominently expressed in the [epithelial cell of lung](/details-cell/CL0000082) (CSI: 7.12) and, more specifically, the [pulmonary alveolar type 2 cell](/details-cell/CL0002063) (CSI: 5.96), which are responsible for producing and secreting pulmonary surfactant. Significant expression is also noted in [lung ciliated cell](/details-cell/CL1000271) and [pulmonary alveolar type 1 cell](/details-cell/CL0002062), reinforcing its role as a key component of the lung's cellular machinery. Beyond the respiratory system, [SFTA2](/details-gene/389376) expression extends to other secretory epithelial tissues. It shows significant expression in the [kidney loop of Henle thin descending limb epithelial cell](/details-cell/CL1001111) (CSI: 4.20), [foveolar cell of stomach](/details-cell/CL0002179) (CSI: 2.00), and [pancreatic ductal cell](/details-cell/CL0002079) (CSI: 1.95). This pattern suggests that while its primary role may be in the lung, it could participate in broader physiological processes related to epithelial secretion and mucosal surfaces in multiple organs. ## Pathways and Molecular Function Functional annotation aligns with the observed expression pattern, placing [SFTA2](/details-gene/389376) squarely within the secretory pathway. Gene Ontology terms indicate its localization to the [Extracellular region](/details-cell/GO:0005576), with processing occurring via the [Golgi apparatus](/details-cell/GO:0005794) and [Transport vesicle](/details-cell/GO:0030133). This is consistent with its high expression in professional secretory cells like [pulmonary alveolar type 2 cell](/details-cell/CL0002063). Research has identified [SFTA2](/details-gene/389376) as a secreted peptide whose expression is modulated by lipopolysaccharide (LPS), a component of gram-negative bacteria, but not by hyperoxia ([Link](https://doi.org/10.1371/journal.pone.0040011)). This suggests a specific role in the host's innate immune response to bacterial components, particularly within the lung, rather than a general stress-response function. ## Research Directions The specific expression of [SFTA2](/details-gene/389376) in lung epithelial cells and its regulation by bacterial LPS point toward a specialized function in pulmonary host defense. This opens several avenues for future investigation. **Proposed Hypotheses:** 1. Given its secretory nature and upregulation by LPS, [SFTA2](/details-gene/389376) may function as an opsonin or a danger-associated molecular pattern (DAMP) that modulates the inflammatory response of alveolar macrophages and epithelial cells during bacterial pneumonia. 2. The expression of [SFTA2](/details-gene/389376) in diverse mucosal epithelia (lung, stomach, pancreas) suggests it may contribute to a common mechanism of maintaining barrier integrity or regulating the local microbiome at these surfaces. **Suggested Experimental Approach:** To test the hypothesis that [SFTA2](/details-gene/389376) plays a direct role in pulmonary host defense, a conditional knockout mouse model could be generated with specific deletion in alveolar type 2 cells. These mice and their wild-type littermates would be challenged via intratracheal instillation of *Pseudomonas aeruginosa*. The impact of [SFTA2](/details-gene/389376) deletion could be assessed by quantifying bacterial clearance (colony-forming units in lung homogenates), measuring inflammatory cytokine levels (e.g., TNF-alpha, IL-6) in bronchoalveolar lavage fluid, and evaluating lung injury and immune cell infiltration through histopathology. **Therapeutic Potential:** As a secreted protein, SFTA2 is an accessible target. Its induction during bacterial stimulation suggests a protective role. Therefore, administration of recombinant SFTA2 protein could be explored as a potential therapeutic strategy (activation) to augment the innate immune response in patients with severe bacterial pneumonia or those at risk for ventilator-associated pneumonia. It could also serve as a valuable biomarker in bronchoalveolar lavage fluid to monitor the host response to lung infections.

Genular Protein ID: 374571956

Symbol: SFTA2_HUMAN

Name: Surfactant-associated protein 2

UniProtKB Accession Codes:

Q6UW10 A2ABK7 A2ACH1 B7ZCJ7

Database IDs:

AGR 1 AlphaFoldDB 1 Antibodypedia 1 Bgee 1 BioGRID 1 BioGRID-ORCS 1 BioMuta 1 CCDS 1 CTD 1 DNASU 1 DisGeNET 1 EMBL 9 Ensembl 5 ExpressionAtlas 1 GO 3 GeneCards 1 GeneTree 1 GenomeRNAi 1 GlyCosmos 1 GlyGen 1 HGNC 1 HOGENOM 1 HPA 1 InParanoid 1 IntAct 1 InterPro 1 KEGG 1 MANE-Select 1 MassIVE 1 NCBI Taxonomy 1 OMA 1 OpenTargets 1 PANTHER 2 PRO 1 PathwayCommons 1 PaxDb 1 PeptideAtlas 1 Pfam 1 PharmGKB 1 Pharos 1 PhosphoSitePlus 1 PhylomeDB 1 Proteomes 1 RNAct 1 RefSeq 1 STRING 1 SignaLink 1 TreeFam 1 UCSC 1 VEuPathDB 1 eggNOG 1 iPTMnet 1 neXtProt 1

Citations:

PubMed ID: 12975309

Title: The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment.

PubMed ID: 12975309

DOI: 10.1101/gr.1293003

PubMed ID: 14574404

Title: The DNA sequence and analysis of human chromosome 6.

PubMed ID: 14574404

DOI: 10.1038/nature02055

PubMed ID: 15489334

Title: The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

PubMed ID: 15489334

DOI: 10.1101/gr.2596504

PubMed ID: 15340161

Title: Signal peptide prediction based on analysis of experimentally verified cleavage sites.

PubMed ID: 15340161

DOI: 10.1110/ps.04682504

PubMed ID: 22768197

Title: SFTA2--a novel secretory peptide highly expressed in the lung--is modulated by lipopolysaccharide but not hyperoxia.

PubMed ID: 22768197

DOI: 10.1371/journal.pone.0040011

Sequence Information:

  • Length: 78
  • Mass: 8396
  • Checksum: 4470CEE55D025483
  • Sequence:
    • MGSGLPLVLL LTLLGSSHGT GPGMTLQLKL KESFLTNSSY ESSFLELLEK LCLLLHLPSG 
TSVTLHHARS QHHVVCNT