Details for: CA13

Gene ID: 377677

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: CA13

Ensembl ID: ENSG00000185015

Description: carbonic anhydrase 13

Cell Significance Landscape

Associated with

Significant Cells

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

  • epithelial cell of lower respiratory tract CL0002632
    CSI 5.4
    rCSI 4.18%
    PRS 99.5
  • secretory cell CL0000151
    CSI 4.8
    rCSI 5.01%
    PRS 98.76
  • lamp5 GABAergic cortical interneuron CL4023011
    CSI 4.55
    rCSI 7.64%
    PRS 96.67
  • mesothelial cell CL0000077
    CSI 3.76
    rCSI 14.72%
    PRS 95.33
  • colon epithelial cell CL0011108
    CSI 3.57
    rCSI 3.74%
    PRS 98.78
  • conjunctival epithelial cell CL1000432
    CSI 3.06
    rCSI 4.67%
    PRS 98.52
  • lung secretory cell CL1000272
    CSI 2.98
    rCSI 7.37%
    PRS 99.42
  • retinal cone cell CL0000573
    CSI 2.88
    rCSI 4.63%
    PRS 96.62
  • BEST4+ enteroycte CL4030026
    CSI 2.64
    rCSI 3.29%
    PRS 98.58
  • colonocyte CL1000347
    CSI 2.5
    rCSI 3.59%
    PRS 98.72
  • enterocyte CL0000584
    CSI 2.48
    rCSI 4%
    PRS 97.92
  • cardiac neuron CL0010022
    CSI 2.04
    rCSI 6.53%
    PRS 98.61
  • cardiac muscle cell CL0000746
    CSI 1.89
    rCSI 2.71%
    PRS 96.63
  • caudal ganglionic eminence derived cortical interneuron CL4023064
    CSI 1.88
    rCSI 3.33%
    PRS 96.47
  • regular atrial cardiac myocyte CL0002129
    CSI 1.72
    rCSI 5.53%
    PRS 97.49
  • regular ventricular cardiac myocyte CL0002131
    CSI 1.28
    rCSI 8.01%
    PRS 96.96
  • megakaryocyte CL0000556
    CSI 1.1
    rCSI 4.75%
    PRS 97.94

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.

Comma-separated if multiple.
Comma-separated if multiple.
Legend:
  • Query Gene
  • 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 [CA13](/details-gene/377677), or Carbonic Anhydrase 13, is a protein-coding gene located on chromosome 8q21.2. As a member of the carbonic anhydrase family of metalloenzymes, it plays a fundamental role in metabolism by catalyzing the reversible hydration of carbon dioxide to bicarbonate and protons, a process central to pH regulation and ion transport. This function is annotated as carbonate dehydratase activity ([GO:0004089](https://www.ebi.ac.uk/QuickGO/term/GO:0004089)) and is part of the 'Reversible hydration of carbon dioxide' pathway ([R-HSA-1475029](https://reactome.org/content/detail/R-HSA-1475029)). Primarily localized to the cytoplasm ([GO:0005737](https://www.ebi.ac.uk/QuickGO/term/GO:0005737)), [CA13](/details-gene/377677) shows its most significant expression in a variety of epithelial and secretory cells, particularly those of the respiratory and digestive systems, as well as in specific neuronal and cardiac cell types, suggesting a broad role in maintaining physiological homeostasis across multiple tissues. ## Cellular Roles and Expression Landscape The expression profile of [CA13](/details-gene/377677) highlights its crucial function in tissues characterized by active secretion and ion exchange. **Overall**, the gene demonstrates the highest significance in epithelial and secretory cell populations. It is a top marker in the [epithelial cell of lower respiratory tract](/details-cell/CL0002632) (CSI: 5.40) and [lung secretory cell](/details-cell/CL1000272) (CSI: 2.98), indicating a primary role in the physiology of the airway. This is complemented by its high significance in [secretory cell](/details-cell/CL0000151) (CSI: 4.80) more broadly. A similar pattern is observed in the gastrointestinal tract, with high CSI scores in [colon epithelial cell](/details-cell/CL0011108) (CSI: 3.57), [colonocyte](/details-cell/CL1000347) (CSI: 2.50), [enterocyte](/details-cell/CL0000584) (CSI: 2.48), and specialized [BEST4+ enteroycte](/details-cell/CL4030026) (CSI: 2.64). Furthermore, its relevance in [mesothelial cell](/details-cell/CL0000077) (CSI: 3.76) and [conjunctival epithelial cell](/details-cell/CL1000432) (CSI: 3.06) underscores its widespread importance in lining and secretory surfaces throughout the body. Interestingly, [CA13](/details-gene/377677) also shows notable significance in specific excitable cell types. It is highly ranked in the [lamp5 GABAergic cortical interneuron](/details-cell/CL4023011) (CSI: 4.55), suggesting a specialized function in a subset of inhibitory neurons. A role in the cardiovascular system is also suggested by its expression in [cardiac neuron](/details-cell/CL0010022) (CSI: 2.04) and [cardiac muscle cell](/details-cell/CL0000746) (CSI: 1.89), particularly the [regular atrial cardiac myocyte](/details-cell/CL0002129) (CSI: 1.72). This diverse expression pattern points to a fundamental housekeeping role in pH balance that is adapted for the specialized physiological demands of different cell types. ## Pathways and Molecular Function The molecular function of [CA13](/details-gene/377677) is well-defined as a zinc-dependent enzyme involved in pH regulation. Its primary annotated molecular function is carbonate dehydratase activity ([GO:0004089](https://www.ebi.ac.uk/QuickGO/term/GO:0004089)), which requires zinc ion binding ([GO:0008270](https://www.ebi.ac.uk/QuickGO/term/GO:0008270)) for its catalytic mechanism, as demonstrated by crystallographic studies ([Link](https://doi.org/10.1002/prot.22144)). This activity is a key step in the 'Reversible hydration of carbon dioxide' ([R-HSA-1475029](https://reactome.org/content/detail/R-HSA-1475029)) and the broader one-carbon metabolic process ([GO:0006730](https://www.ebi.ac.uk/QuickGO/term/GO:0006730)). Functionally, this enzymatic activity is critical in cells with high metabolic rates or those involved in transepithelial ion transport. In respiratory and intestinal epithelial cells, the rapid conversion of CO2 to bicarbonate is essential for secreting bicarbonate ions, which in turn regulates the pH of mucosal surfaces. In neurons and muscle cells, this activity is crucial for managing pH shifts resulting from intense metabolic and electrical activity, thereby maintaining cellular integrity and function. The protein is primarily located in the cytoplasm ([GO:0005737](https://www.ebi.ac.uk/QuickGO/term/GO:0005737)) and cytosol ([GO:0005829](https://www.ebi.ac.uk/QuickGO/term/GO:0005829)), positioning it to buffer the intracellular environment effectively. ## Research Directions The well-defined enzymatic function and specific cellular expression pattern of [CA13](/details-gene/377677) provide a strong foundation for targeted functional studies. While its general role is understood, its specific contribution relative to other carbonic anhydrase isozymes in these key cell types warrants further investigation. **Proposed Testable Hypotheses:** 1. Given its high significance in [epithelial cell of lower respiratory tract](/details-cell/CL0002632), [CA13](/details-gene/377677) is essential for maintaining the pH and bicarbonate concentration of the airway surface liquid, a critical factor for proper mucociliary clearance. Its dysfunction could contribute to pathologies characterized by mucus accumulation, such as chronic obstructive pulmonary disease (COPD) or cystic fibrosis-like symptoms. 2. The high CSI score in [lamp5 GABAergic cortical interneuron](/details-cell/CL4023011) suggests that [CA13](/details-gene/377677) plays a specialized role in regulating intracellular pH and bicarbonate-dependent GABAergic signaling in this neuronal subtype. Inhibition of [CA13](/details-gene/377677) may alter the inhibitory tone provided by these interneurons, potentially impacting cortical network activity. 3. In [colon epithelial cell](/details-cell/CL0011108), [CA13](/details-gene/377677) likely facilitates the high-capacity bicarbonate secretion required to neutralize luminal acid and create an optimal pH environment for digestive enzymes and the gut microbiome. **Proposed Experimental Approach:** To test the first hypothesis regarding the respiratory function of [CA13](/details-gene/377677), a study using primary human bronchial epithelial cells cultured at an air-liquid interface (ALI) would be highly informative. 1. **Genetic Perturbation:** Use CRISPR-Cas9 to generate a stable knockout of [CA13](/details-gene/377677) in these cells. 2. **Functional Readouts:** Measure the pH and bicarbonate concentration of the apical airway surface liquid in knockout versus wild-type cultures using ion-selective microelectrodes. 3. **Physiological Assessment:** Evaluate the impact on mucociliary clearance by measuring ciliary beat frequency via high-speed video microscopy and assessing mucus transport rates using fluorescent microbeads. 4. **Transcriptomic Analysis:** Perform RNA-sequencing to determine if the loss of [CA13](/details-gene/377677) induces compensatory changes in other carbonic anhydrases or ion transporter genes. **Therapeutic Potential:** As an enzyme, [CA13](/details-gene/377677) is a potentially druggable target. The carbonic anhydrase family is already targeted by a class of drugs (e.g., acetazolamide). While [CA13](/details-gene/377677) is an intracellular protein, making it inaccessible to antibody-based therapies, small molecule inhibitors could be developed. If its activity is found to be aberrantly high in specific disease contexts, such as certain cancers that rely on pH regulation for survival and metastasis, or in respiratory diseases involving altered ion transport, a specific inhibitor for [CA13](/details-gene/377677) could offer a therapeutic benefit. The strategy would focus on **inhibition** to normalize cellular pH dynamics. However, the development of isozyme-specific inhibitors would be critical to avoid off-target effects, given the presence of multiple carbonic anhydrases in the human body.

Genular Protein ID: 3591493752

Symbol: CAH13_HUMAN

Name: Carbonic anhydrase 13

UniProtKB Accession Codes:

Q8N1Q1

Database IDs:

AGR 1 AlphaFoldDB 1 Antibodypedia 1 Bgee 1 BindingDB 1 BioGRID 1 BioGRID-ORCS 1 BioMuta 1 CCDS 1 CDD 1 CTD 1 ChEBI 8 ChEMBL 1 ChiTaRS 1 DMDM 1 DNASU 1 DisGeNET 1 DrugBank 4 DrugCentral 1 EC 2 EMBL 2 Ensembl 1 EvolutionaryTrace 1 GO 7 Gene3D 1 GeneCards 1 GeneTree 1 GenomeRNAi 1 HGNC 1 HOGENOM 1 HPA 1 InParanoid 1 IntAct 1 InterPro 4 KEGG 1 MANE-Select 1 MIM 1 MassIVE 1 NCBI Taxonomy 1 OGP 1 OMA 1 OpenTargets 1 OrthoDB 1 PANTHER 2 PDB 16 PDBsum 16 PRO 1 PROSITE 2 PathwayCommons 1 PaxDb 1 PeptideAtlas 1 Pfam 1 PharmGKB 1 Pharos 1 PhosphoSitePlus 1 PhylomeDB 1 Proteomes 1 ProteomicsDB 1 Pumba 1 RNAct 1 Reactome 1 RefSeq 1 Rhea 1 SABIO-RK 1 SMART 1 SMR 1 STRING 1 SUPFAM 1 SignaLink 1 TreeFam 1 UCSC 1 VEuPathDB 1 eggNOG 1 iPTMnet 1 jPOST 1 neXtProt 1

Citations:

PubMed ID: 14702039

Title: Complete sequencing and characterization of 21,243 full-length human cDNAs.

PubMed ID: 14702039

DOI: 10.1038/ng1285

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: 14600151

Title: Characterization of CA XIII, a novel member of the carbonic anhydrase isozyme family.

PubMed ID: 14600151

DOI: 10.1074/jbc.m308984200

PubMed ID: 18618712

Title: Crystal structure of human carbonic anhydrase XIII and its complex with the inhibitor acetazolamide.

PubMed ID: 18618712

DOI: 10.1002/prot.22144

Sequence Information:

  • Length: 262
  • Mass: 29443
  • Checksum: AE677F028ED729FE
  • Sequence:
    • MSRLSWGYRE HNGPIHWKEF FPIADGDQQS PIEIKTKEVK YDSSLRPLSI KYDPSSAKII 
SNSGHSFNVD FDDTENKSVL RGGPLTGSYR LRQVHLHWGS ADDHGSEHIV DGVSYAAELH 
VVHWNSDKYP SFVEAAHEPD GLAVLGVFLQ IGEPNSQLQK ITDTLDSIKE KGKQTRFTNF 
DLLSLLPPSW DYWTYPGSLT VPPLLESVTW IVLKQPINIS SQQLAKFRSL LCTAEGEAAA 
FLVSNHRPPQ PLKGRKVRAS FH