Structural organization of the mitochondrial DNA control region in Aedes aegypti.

RONDAN DUEÑAS, J.C., GARDENAL, C.N., ALBRIEU LLINÁS, G. Y PANZETTA-DUTARI, G.D.

GENOME

Año: 2006 vol. 49 p. 931 - 937

0831-2796

Abstract             The complete A+T- rich region of Aedes aegypti mitochondrial DNA has been cloned and sequenced. In Argentinean populations of the species, a polymorphism in the length of the amplified fragment was observed. Nucleotide sequence comparison between the shortest and longest A+T rich amplified fragments detected, revealed the presence of two types of tandemly repeated blocks. The size variation observed in natural populations is mainly due to the presence of a variable number of a 181 bp tandem repeat unit located towards the 12S rRNA gene end.  The size of the longest A+T- rich region was of 2,070 bp, representing the largest control sequence reported for any mosquito species.  Few relevant short blocks of primary sequence similarity conserved in the control region of mosquitoes and other insects were detected scattered through the whole region.  Five putative stem-loop secondary structures were found, one of them flanked by conserved sequences described in other insects. Our results suggest that there are no universal models of structure-function relations in the control region of insects’ mtDNA.  In addition, we identified a short A+T-rich variable segment in the Ae. aegyti control region which would be suitable for population genetic studies.