Squid express conserved ADAR orthologs that possess novel features

Frontiers in Genome Editing

Genome Editing

Noa Liscovitch-Brauer¹  Eli Eisenberg¹  Joshua J. C. Rosenthal²  Isabel C. Vallecillo-Viejo²  Gjendine Voss²  Caroline B. Albertin² 

[1] Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel;The Eugene Bell Center, Marine Biological Laboratory, Woods Hole, MA, United States;

关键词: squid;    Doryteuthis pealeii;    cephalopods;    RNA editing;    ADAR;    adenosine deamination;    genetic recoding;   

DOI  :  10.3389/fgeed.2023.1181713

 received in 2023-03-07, accepted in 2023-05-15,  发布年份 2023

来源: Frontiers

【 摘 要 】

The coleoid cephalopods display unusually extensive mRNA recoding by adenosine deamination, yet the underlying mechanisms are not well understood. Because the adenosine deaminases that act on RNA (ADAR) enzymes catalyze this form of RNA editing, the structure and function of the cephalopod orthologs may provide clues. Recent genome sequencing projects have provided blueprints for the full complement of coleoid cephalopod ADARs. Previous results from our laboratory have shown that squid express an ADAR2 homolog, with two splice variants named sqADAR2a and sqADAR2b and that these messages are extensively edited. Based on octopus and squid genomes, transcriptomes, and cDNA cloning, we discovered that two additional ADAR homologs are expressed in coleoids. The first is orthologous to vertebrate ADAR1. Unlike other ADAR1s, however, it contains a novel N-terminal domain of 641 aa that is predicted to be disordered, contains 67 phosphorylation motifs, and has an amino acid composition that is unusually high in serines and basic amino acids. mRNAs encoding sqADAR1 are themselves extensively edited. A third ADAR-like enzyme, sqADAR/D-like, which is not orthologous to any of the vertebrate isoforms, is also present. Messages encoding sqADAR/D-like are not edited. Studies using recombinant sqADARs suggest that only sqADAR1 and sqADAR2 are active adenosine deaminases, both on perfect duplex dsRNA and on a squid potassium channel mRNA substrate known to be edited in vivo. sqADAR/D-like shows no activity on these substrates. Overall, these results reveal some unique features in sqADARs that may contribute to the high-level RNA recoding observed in cephalopods.

【 授权许可】

Unknown   
Copyright © 2023 Vallecillo-Viejo, Voss, Albertin, Liscovitch-Brauer, Eisenberg and Rosenthal.