High impact information on CA14

• Immunostaining for CA XIV was found on neuronal membranes and axons in both mouse and human brain [1].
• Other CA XIV-positive sites included the hippocampus, corpus callosum, cerebellar white matter and peduncles, pyramidal tract, and choroid plexus [1].
• These observations make CA XIV a likely candidate for the extracellular CA postulated to have an important role in modulating excitatory synaptic transmission in brain [1].
• Membrane polarity is apical for CAXIV, basolateral for CAXII, and apical and basolateral for CAIV [2].
• CAXII and CAXIV may also be associated with transporters in normal kidney and CAIX in RCCs [2].

Biological context of CA14

• The deduced amino acid sequence of CA XIV showed an overall similarity of 29-46% to other active CA isozymes [3].
• The CA XIV gene was localized to human chromosome 1q21 [3].

Anatomical context of CA14

• RNA dot-blot analysis for CA XIV mRNA expression showed a strong signal in all parts of the human brain and a weaker signal in the colon, small intestine, urinary bladder, and kidney [3].
• No CA XIV mRNA was seen in the salivary gland and pancreas [3].
• Sequencing was performed for the MICB alleles CA14, CA15, CA17, CA23 and CA26 isolated from different cell lines [4].
• RESULTS: Immunofluorescence staining showed abundant expression of CA XIV in apical plasma membranes of the S1 and S2 segments of proximal tubules, and weaker staining in the basolateral membranes [5].

Associations of CA14 with chemical compounds

• The full-length hCA XIV is an enzyme showing a medium-low catalytic activity, quite similar to that of hCA XII, with the following kinetic parameters at 20 degrees C and pH 7.5, for the CO2 hydration reaction: k(cat) = 3.12 x 10(5) s(-1) and k(cat)/K(M) = 3.9 x 10(7) M(-1) s(-1) [6].
• CA XIV showed low activity and was sensitive to acetazolamide, but not to sulfonamide [3].
• Carbonic anhydrase XIV: luminal expression suggests key role in renal acidification [5].
• Polyclonal antibodies against mouse CA XIV were utilized for immunofluorescence to examine the pattern of expression of CA XIV in the nephron of both rat and mouse kidney [5].
• The sulfanilamides acylated at the 4-amino group with short aliphatic/aromatic moieties incorporating 2-6 carbon atoms showed modest hCA XIV inhibitory activity (K(I)-s in the range of 1.25-4.2 microM) which were anyhow better than that of sulfanilamide (K(I) of 5.4 microM) [7].

Other interactions of CA14

• The membrane-bound carbonic anhydrase (CA) IV in muscle increased in the lowlanders by 39 %, whereas CA XIV decreased by 23-47 % [8].

Analytical, diagnostic and therapeutic context of CA14

• METHODS: RT-PCR and Western blot analyses were used to demonstrate CA XIV mRNA and protein in extracts of cortex and medulla of mouse kidney [5].
• RESULTS: Northern blot analysis showed no detectable signal for CA XIV mRNA expression in normal and cancer cells [9].

References