SECISBP2
Function
mRNA-binding protein that binds to the SECIS (selenocysteine insertion sequence) element present in the 3'-UTR of mRNAs encoding selenoproteins and facilitates the incorporation of the rare amino acid selenocysteine (PubMed:35709277). Insertion of selenocysteine at UGA codons is mediated by SECISBP2 and EEFSEC: SECISBP2 (1) specifically binds the SECIS sequence once the 80S ribosome encounters an in-frame UGA codon and (2) contacts the RPS27A/eS31 of the 40S ribosome before ribosome stalling (PubMed:35709277). (3) GTP-bound EEFSEC then delivers selenocysteinyl-tRNA(Sec) to the 80S ribosome and adopts a preaccommodated state conformation (PubMed:35709277). (4) After GTP hydrolysis, EEFSEC dissociates from the assembly, selenocysteinyl-tRNA(Sec) accommodates, and peptide bond synthesis and selenoprotein elongation occur (PubMed:35709277).
Involvement in disease
Thyroid hormone metabolism, abnormal, 1
THMA1
A disorder associated with a reduction in type II iodothyronine deiodinase activity.
None
The disease is caused by variants affecting the gene represented in this entry.
Tissue Specificity
Expressed at high levels in testis.
Cellular localization
- Isoform 1
- Nucleus
- Isoform 2
- Mitochondrion
Alternative names
SBP2, SECISBP2, Selenocysteine insertion sequence-binding protein 2, SECIS-binding protein 2