CBS pair domain found in Hypoxic Response Protein 1 (HRP1) -like proteinds
Mycobacterium tuberculosis adapts to cellular stresses by upregulation of the dormancy survival regulon. Hypoxic response protein 1 (HRP1) is encoded by one of the most strongly upregulated genes in the dormancy survival regulon. HRP1 is a 'CBS-domain-only protein; however unlike other CBS containing proteins it does not appear to bind AMP. The biological function of the protein remains unclear, but is thought to contribute to the modulation of the host immune response. The CBS domain, named after human CBS, is a small domain originally identified in cystathionine beta-synthase and is subsequently found in a wide range of different proteins. CBS domains usually occur in tandem repeats. They associate to form a so-called Bateman domain or a CBS pair based on crystallographic studies in bacteria. The CBS pair was used as a basis for this cd hierarchy since the human CBS proteins can adopt the typical core structure and form an intramolecular CBS pair. The interface between the two CBS domains forms a cleft that is a potential ligand binding site. The CBS pair coexists with a variety of other functional domains and this has been used to help in its classification here. It has been proposed that the CBS domain may play a regulatory role, although its exact function is unknown. Mutations of conserved residues within this domain are associated with a variety of human hereditary diseases, including congenital myotonia, idiopathic generalized epilepsy, hypercalciuric nephrolithiasis, and classic Bartter syndrome (CLC chloride channel family members), Wolff-Parkinson-White syndrome (gamma 2 subunit of AMP-activated protein kinase), retinitis pigmentosa (IMP dehydrogenase-1), and homocystinuria (cystathionine beta-synthase).
Jiyao W et al.(2023). "The conserved domain database in 2023.",