Intragenic duplications in diatom algae: evolution and expression

  • Morozov A.A. 1
  • Galachyants Yu.P. 1
  • Marchenkov A.M. 1
  • Bairamova E.M. 1
  • 1 Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya Str., 3, Irkutsk, 664033, Russia
Keywords: Duplications, diatoms, protein evolution


In our earlier work, multiple diatom protein-coding genes were found to consist of long repeats, in some cases even including several copies of the entire protein within a single open reading frame. 28 of them were amplified and sequenced from Fragilaria radians total DNA, thus proving that they are not assembly or annotation artifacts. Out of these 28, 16 were successfully sequenced from cDNA of the same species, confirming their expression and, hypothetically, functionality. Much like the original set of unvalidated sequences, this group shows little functional and structural specificity. Most duplications are shared with other diatom species, implying either multiple independent duplications or an ancient duplication event and vertical inheritance.