Small RNAs from RNA virus-like contigs.

<p>Panels to the left show the distribution of 20-30nt small RNAs along the length of the virus-like contig, and panels to the right show the size distribution small RNA reads coloured by the 5' base (U red, G yellow, C blue, A green). Read counts above the x-axis represent reads mapping to the positive sense (coding) sequence and counts below the x-axis represent reads mapping to the complementary sequence. For the dog whelk (A-D), only reads from the oxidised library are shown. Other dog whelk libraries display similar distributions and the small-RNA ‘hotspot’ pattern along the contig is highly repeatable (<a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1007533#pgen.1007533.s006" target="_blank">S6 Fig</a>). Small RNAs from the two segments of the orthomyxovirus (A and B) show strong strand bias to the negative strand and no 5' base composition bias. Those from the first rhabdo-like virus (C) display little strand bias and no base composition bias, and those from the second rhabdo virus-like contig, which is a probable EVE (D), derive only from the negative strand and display a very strong 5' U bias. There were insufficient reads from the positive strand of this virus to detect a ping-pong signature. Small RNAs from the four dog whelk contigs all display 28nt peaks. Small RNAs from the bunya/phlebo-like virus identified in the brown alga (E) derive from both strands, and show a strong 5' U bias with a peak size of 21nt. The data required to plot the size distributions are provided in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1007533#pgen.1007533.s014" target="_blank">S5 Table</a>.