000165922 001__ 165922 000165922 005__ 20260116002211.0 000165922 0247_ $$2doi$$a10.1038/s41598-019-54181-3 000165922 0248_ $$2sideral$$a143304 000165922 037__ $$aART-2019-143304 000165922 041__ $$aeng 000165922 100__ $$aDeRisi, Joseph L. 000165922 245__ $$aAn exploration of ambigrammatic sequences in narnaviruses 000165922 260__ $$c2019 000165922 5060_ $$aAccess copy available to the general public$$fUnrestricted 000165922 5203_ $$aNarnaviruses have been described as positive-sense RNA viruses with a remarkably simple genome of ~3 kb, encoding only a highly conserved RNA-dependent RNA polymerase (RdRp). Many narnaviruses, however, are ‘ambigrammatic’ and harbour an additional uninterrupted open reading frame (ORF) covering almost the entire length of the reverse complement strand. No function has been described for this ORF, yet the absence of stops is conserved across diverse narnaviruses, and in every case the codons in the reverse ORF and the RdRp are aligned. The >3 kb ORF overlap on opposite strands, unprecedented among RNA viruses, motivates an exploration of the constraints imposed or alleviated by the codon alignment. Here, we show that only when the codon frames are aligned can all stop codons be eliminated from the reverse strand by synonymous single-nucleotide substitutions in the RdRp gene, suggesting a mechanism for de novo gene creation within a strongly conserved amino-acid sequence. It will be fascinating to explore what implications this coding strategy has for other aspects of narnavirus biology. Beyond narnaviruses, our rapidly expanding catalogue of viral diversity may yet reveal additional examples of this broadly-extensible principle for ambigrammatic-sequence development. 000165922 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttps://creativecommons.org/licenses/by/4.0/deed.es 000165922 590__ $$a3.998$$b2019 000165922 591__ $$aMULTIDISCIPLINARY SCIENCES$$b16 / 70 = 0.229$$c2019$$dQ1$$eT1 000165922 592__ $$a1.341$$b2019 000165922 593__ $$aMultidisciplinary$$c2019$$dQ1 000165922 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000165922 700__ $$aHuber, Greg 000165922 700__ $$aKistler, Amy 000165922 700__ $$aRetallack, Hanna 000165922 700__ $$aWilkinson, Michael 000165922 700__ $$0(orcid)0000-0001-7276-2942$$aYllanes, David 000165922 773__ $$g9 (2019), 17982 [9 pp.]$$pSci. rep. (Nat. Publ. Group)$$tScientific reports (Nature Publishing Group)$$x2045-2322 000165922 8564_ $$s3404101$$uhttps://zaguan.unizar.es/record/165922/files/texto_completo.pdf$$yVersión publicada 000165922 8564_ $$s2666038$$uhttps://zaguan.unizar.es/record/165922/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000165922 909CO $$ooai:zaguan.unizar.es:165922$$particulos$$pdriver 000165922 951__ $$a2026-01-15-21:56:40 000165922 980__ $$aARTICLE