A model for the tertiary structure of mammalian mitochondrial transfer RNAs lacking the entire 'dihydrouridine' loop and stem.

AUTOR(ES)

de Bruijn, M H

RESUMO

The mammalian mitochondrial tRNA(AGY)Ser is unique in lacking the entire dihydrouridine arm. This reduces its secondary structure to a 'truncated cloverleaf'. Experimental evidence on the tertiary structure has been obtained by chemically probing the conformation of both the bovine and human species in their native conformation and at various stages of denaturation. A structural model of the bovine tRNA is presented based on the results of this chemical probing, on a comparison between nine homologous 'truncated cloverleaf' secondary structures and on analogies with the crystal structure of yeast phenylalanine tRNA. The proposed structure is very similar in shape to that of yeast tRNA(Phe) but is slightly smaller in size. It is defined by a unique set of tertiary interactions. Structural considerations suggest that other mammalian mitochondrial tRNAs have smaller dimensions as well.

Documentos Relacionados

• A mammalian mitochondrial serine transfer RNA lacking the "dihydrouridine" loop and stem.
• Tritium exchange on transfer RNA: slowly exchanging protons sensitive to a change in the dihydrouridine stem.
• Mammalian mitochondrial transfer RNAs: chromatographic properties, size and origin.
• Editing corrects mispairing in the acceptor stem of bean and potato mitochondrial phenylalanine transfer RNAs.
• A spin label study of the thermal unfolding of secondary and tertiary structure in E. colic transfer RNAs.