HELZ2: a new, interferon-regulated, human 3'-5' exoribonuclease of the RNB family is expressed from a non-canonical initiation codon.

ABSTRACT: Proteins containing a RNB domain, originally identified in Escherichia coli RNase II, are widely present throughout the tree of life. Many RNB proteins have 3'-5' exoribonucleolytic activity but some have lost catalytic activity during evolution. Database searches identified a new RNB domain-containing protein in human: HELZ2. Analysis of genomic and expression data combined with evolutionary information suggested that the human HELZ2 protein is produced from an unforeseen non-canonical initiation codon in Hominidae. This unusual property was confirmed experimentally, extending the human protein by 247 residues. Human HELZ2 was further shown to be an active ribonuclease despite the substitution of a key residue in its catalytic center. HELZ2 RNase activity is lost in cells from some cancer

SUBMITTER: Huntzinger E 

PROVIDER: S-EPMC10516660 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature