Dyskerin (DKC) Recombinant Protein

This gene functions in two distinct complexes. It plays an active role in telomerase stabilization and maintenance, as well as recognition of snoRNAs containing H/ACA sequences which provides stability during biogenesis and assembly into H/ACA small nucleolar RNA ribonucleoproteins (snoRNPs). This gene is highly conserved and widely expressed, and may play additional roles in nucleo-cytoplasmic shuttling, DNA damage response, and cell adhesion. Mutations have been associated with X-linked dyskeratosis congenita. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014]

dyskerin: Isoform 1: Required for ribosome biogenesis and telomere maintenance. Probable catalytic subunit of H/ACA small nucleolar ribonucleoprotein (H/ACA snoRNP) complex, which catalyzes pseudouridylation of rRNA. This involves the isomerization of uridine such that the ribose is subsequently attached to C5, instead of the normal N1. Each rRNA can contain up to 100 pseudouridine ('psi') residues, which may serve to stabilize the conformation of rRNAs. Also required for correct processing or intranuclear trafficking of TERC, the RNA component of the telomerase reverse transcriptase (TERT) holoenzyme. Defects in DKC1 are a cause of dyskeratosis congenita X- linked recessive (XDKC). XDKC is a rare, progressive bone marrow failure syndrome characterized by the triad of reticulated skin hyperpigmentation, nail dystrophy, and mucosal leukoplakia. Early mortality is often associated with bone marrow failure, infections, fatal pulmonary complications, or malignancy. Defects in DKC1 are the cause of Hoyeraal-Hreidarsson syndrome (HHS). HHS is a multisystem disorder affecting males and is characterized by aplastic anemia, immunodeficiency, microcephaly, cerebellar hypoplasia, and growth retardation. Belongs to the pseudouridine synthase TruB family. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 5.4.99.-; RNA processing; Nucleolus; Lyase; Isomerase; RNA-binding

Chromosomal Location of Human Ortholog: Xq28

Cellular Component: cytoplasm; nucleolus; nucleoplasm; nucleus; telomerase holoenzyme complex

Molecular Function: protein binding; pseudouridine synthase activity; RNA binding; telomerase activity

Biological Process: box H/ACA snoRNA 3'-end processing; cell proliferation; positive regulation of telomerase activity; positive regulation of telomere maintenance via telomerase; RNA processing; rRNA processing; rRNA pseudouridine synthesis; snRNA pseudouridine synthesis; telomere maintenance; telomere maintenance via telomerase

Disease: Dyskeratosis Congenita, X-linked