Sequence comparison of the rDNA introns from six different species of Tetrahymena

TY - JOUR

T1 - Sequence comparison of the rDNA introns from six different species of Tetrahymena

AU - Nielsen, Henrik

AU - Engberg, J

N1 - Keywords: Base Sequence; DNA, Ribosomal; Evolution; Genes; Nucleic Acid Conformation; RNA, Ribosomal; Sequence Homology, Nucleic Acid; Species Specificity; Tetrahymena

PY - 1985

Y1 - 1985

N2 - We have studied the sequence variation of the rDNA intron among six species of Tetrahymena. From these data, the intron appears to be relatively well conserved in evolution. We have evaluated the sequence variations among the most distant of these species in relation to the secondary structure model for the intron RNA of Cech et al. (Proc. Natl. Acad. Sci. U.S.A. 80, 3903 (83)). Most of the sequence variation in the four new sequences reported here is found in single stranded loops in the model. However, in four cases we found nucleotide substitutions in duplex stem regions, two of them involving compensating base pair changes. Interestingly, one of these is found in a region that is known to be dispensable in the in vitro splicing reaction suggesting differences between the in vivo and in vitro reactions. One of the single nucleotide deletions is found in the so-called "internal guide sequence" which has been implicated in the alignment process during splicing. In conclusion, none of the observed natural sequence variations are in disfavor of the proposed secondary structure model.

AB - We have studied the sequence variation of the rDNA intron among six species of Tetrahymena. From these data, the intron appears to be relatively well conserved in evolution. We have evaluated the sequence variations among the most distant of these species in relation to the secondary structure model for the intron RNA of Cech et al. (Proc. Natl. Acad. Sci. U.S.A. 80, 3903 (83)). Most of the sequence variation in the four new sequences reported here is found in single stranded loops in the model. However, in four cases we found nucleotide substitutions in duplex stem regions, two of them involving compensating base pair changes. Interestingly, one of these is found in a region that is known to be dispensable in the in vitro splicing reaction suggesting differences between the in vivo and in vitro reactions. One of the single nucleotide deletions is found in the so-called "internal guide sequence" which has been implicated in the alignment process during splicing. In conclusion, none of the observed natural sequence variations are in disfavor of the proposed secondary structure model.

M3 - Journal article

C2 - 4059059

SN - 0305-1048

VL - 13

SP - 7445

EP - 7455

JO - Nucleic Acids Research

JF - Nucleic Acids Research

IS - 20

ER -