A secondary structural common core in the ribosomal ITS2 (internal transcribed spacer) of Culexspecies from diverse geographical locations.

In the present study, sequence and structural analysis of ITS2 region (the spacer segment between 5.8S and 28S rRNA of mature rRNA sequences) of 7 Culex species belonging to 5 different geographical locations was carried out. Alignment of the ITS2 sequence from the 7 species revealed 8 homologous domains. Four species namely C. vishnui, C. annulus, C. pipiens, C. quiquefasciatusshowed high sequence (98-100%) and RNA secondary structure similarity. The ITS2 similarity among different species is high despite their varying geographical locations. Several common features of secondary structure are shared among these species, with some of them supported by compensatory changes, suggesting the significant role by ITS2 as an RNA domain during ribosome biogenesis.