AK2

Adenylate kinase 2 is an is_associated_with::enzyme is encoded in humans by the AK2 is_associated_with::gene. The AK2 protein is found in the intermembrane space of the is_associated_with::mitochondrion.

Function
Adenylate kinases are involved in regulating the adenine nucleotide composition within a cell by catalyzing the reversible transfer of phosphate groups among adenine nucleotides. Three isozymes of adenylate kinase, namely 1, 2, and 3, have been identified in vertebrates; this gene encodes isozyme 2. Expression of these isozymes is tissue-specific and developmentally regulated. Isozyme 2 is localized in the mitochondrial intermembrane space and may play a role in apoptosis. Two transcript variants encoding distinct isoforms have been identified for this gene.

AK2 deficiency
Adenylate Kinase 2 (AK2) deficiency in humans causes is_associated_with::hematopoietic defects associated with is_associated_with::sensorineural deafness. Recticular dysgenesis is an autosomal recessive form of human combined is_associated_with::immunodeficiency. It is also characterized by an impaired lymphoid maturation and early differentiation arrest in the myeloid lineage. AK2 deficiency results in absent or a large decrease in the expression of proteins. AK2 is specifically expressed in the stria vascularis of the is_associated_with::inner ear which indicates why individuals with an AK2 deficiency will have sensorineural deafness.