6.5 S RNA; preliminary characterisation of unusual small RNAs in Trypanosoma brucei.

In this paper we report the preliminary characterisation of some unusual small rRNAs isolated from Trypanosoma brucei. These molecules correspond closely in size and properties to the 5 S and 5.8 S rRNAs of other eukaryotes and in addition there are two further small RNAs which we designate 6.5 S RNA. These have been characterised by sucrose gradient centrifugation and electrophoresis in denaturing gels. The two 6.5 S RNAs may be distinguished from each other on the basis of their size and the different conditions required for their dissociation from the ribosomes. They are present in the same abundance as 5.8 S RNA suggesting that they occur once per ribosome.