Herpes-like viral elements and universal subtelomeric ribosomal RNA genes in a chromosome-scale thraustochytrid genome assembly

Collier, J. L.; Rest, J. S.; Gallot-Lavallee, L.; Lavington, E.; Kuo, A.; Jenkins, J. W.; Plott, C.; Pangilinan, J.; Daum, C.; Grigoriev, I. V.; Filloramo, G. V.; Novak Vanclova, A. G.; Archibald, J. M.

doi:10.1101/2023.06.15.545109

bioRxiv · 10.1101/2023.06.15.545109

Herpes-like viral elements and universal subtelomeric ribosomal RNA genes in a chromosome-scale thraustochytrid genome assembly

Collier, J. L.·Rest, J. S.·Gallot-Lavallee, L.·Lavington, E.·Kuo, A.·Jenkins, J. W.·Plott, C.·Pangilinan, J.·Daum, C.·Grigoriev, I. V.·Filloramo, G. V.·Novak Vanclova, A. G.·Archibald, J. M.

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Abstract

We used long-read sequencing to produce a telomere-to-telomere genome assembly for the heterotrophic stramenopile protist Aurantiochytrium limacinum MYA-1381. Its [~]62 Mbp nuclear genome comprises 26 linear chromosomes with a novel configuration: subtelomeric rDNAs are interspersed with long repeated sequence elements denoted as LOng REpeated - TElomere And Rdna Spacers (LORE-TEARS). These repeats may play a role in chromosome end maintenance. A [~]300 Kbp circular herpesvirus-like genomic element is present at a high copy number. A 269 Kbp related virus-like element was found to reside between two complete sets of rRNA and LORE-TEAR sequences on one end of chromosome 15, indicating recent recombination between the viral and nuclear genome. Our data reveal new types of giant endogenous viral elements originating from herpes-like viruses and existing as either stand-alone or integrated elements.

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Collier, J. L., Rest, J. S., Gallot-Lavallee, L., Lavington, E., Kuo, A., Jenkins, J. W., Plott, C., Pangilinan, J., Daum, C., Grigoriev, I. V., Filloramo, G. V., Novak Vanclova, A. G., Archibald, J. M.. 2023-06-15. Herpes-like viral elements and universal subtelomeric ribosomal RNA genes in a chromosome-scale thraustochytrid genome assembly. https://doi.org/10.1101/2023.06.15.545109

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