ribosomal RNAs

[Marta Riutort]

In response to the existence of different sequences for the rDNAs in some
species, we have also found a case, within the Platyhelminthes, in which
various species of a same family have two different types of 18S rDNA
sequences. These two types diverge by around an 8% in their sequence, and
although both seem to be functional (because the secondary structure is
conserved), we have only found one in the form of RNA. (Mol. Biol. Evol.
13(6):824-832). Of course the existence of these two types can affect the
use of this molecule as a phylogenetic tool, if one have (inadvertedly)
sequences of different types for the different species to compare, one will
get a wrong phylogeny.


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  Marta Riutort
  Dpt. de Genetica
  Fac. de Bilogia
  Av. Diagonal, 645
  08071 Barcelona (Spain)

  Tel: 34-3 402 15 00
  Fax: 34-3 411 09 69
  e-mail: martar at porthos.bio.ub.es