TRNT1

The CCA-adding enzyme TRNT1 (EC 2.7.7.25) is an essential enzyme that catalyzes the addition of the CCA terminus to the 3-prime end of tRNA precursors. This reaction is a fundamental prerequisite for mature tRNAs to become aminoacylated and to participate in protein biosynthesis (Lizano et al., 2007 [PubMed 17204286]).[supplied by OMIM

Full Name

tRNA nucleotidyl transferase, CCA-adding, 1

Function

Isoform 1
Adds and repairs the conserved 3'-CCA sequence necessary for the attachment of amino acids to the 3' terminus of tRNA molecules, using CTP and ATP as substrates.
Isoform 2
Adds 2 C residues (CC-) to the 3' terminus of tRNA molecules instead of a complete CCA end as isoform 1 does (in vitro).

Biological Process

Biological Process mitochondrial tRNA 3'-end processing Source:UniProtKB1 Publication
Biological Process tRNA 3'-end processing Source:Reactome
Biological Process tRNA 3'-terminal CCA addition Source:UniProtKB1 Publication
Biological Process tRNA processing Source:GO_Central1 Publication

Cellular Location

Mitochondrion

Involvement in disease

Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay (SIFD):
An autosomal recessive disease characterized by severe sideroblastic anemia with onset in the neonatal period or infancy, recurrent periodic fevers without an infectious etiology, B-cell lymphopenia and hypogammaglobulinemia. Affected individuals show delayed psychomotor development with variable neurodegeneration. Additional variable features include sensorineural hearing loss, retinitis pigmentosa, nephrocalcinosis, and cardiomyopathy.
Retinitis pigmentosa and erythrocytic microcytosis (RPEM):
An autosomal recessive disease characterized by retinitis pigmentosa, red blood cell microcytosis and anisocytosis with mild anemia.