Nucleotide sequence heterogeneity of an RNA phage population

doi:10.1016/0092-8674(78)90223-4

Cell

Volume 13, Issue 4, April 1978, Pages 735-744

https://doi.org/10.1016/0092-8674(78)90223-4 Get rights and content

Abstract

The nucleotide sequence of ³²P-RNA from Qβ phage clones was sampled by two-dimensional polyacrylamide gel electrophoresis of the RNAase T1-resistant oligonucleotides (T1 fingerprinting). About 15% of the clones derived from a multiply passaged Qβ population showed fingerprint patterns which deviated from that of the RNA from the total population. All deviations examined could be attributed to one and, less frequently, to two or more nucleotide transitions. Since the fingerprinting technique allows the analysis of only about 10% of the RNA sequence, we estimate that each viable phage genome in a multiply passaged population differs in one to two positions from the “average” sequence of the parental population. Several deviant clones were tested by growth competition against a “wild-type” population; after 10–20 generations, the resulting phage showed the “wild-type” T1 fingerprint pattern. We propose that a Qβ phage population is in a dynamic equilibrium, with viable mutants arising at a high rate (Batschelet, Domingo and Weissmann, 1976; Domingo, Flavell and Weissmann, 1976) on the one hand, and being strongly selected against on the other. The genome of Qβ phage cannot be described as a defined unique structure, but rather as a weighted average of a large number of different individual sequences.

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^∗: Present address: Centro de Biologia Molecular, Universidad Autónoma de Madrid, Canto Blanco, Madrid, Spain.

^†: This work was initiated by D. S. and completed after her untimely death in 1976.

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Cell

Nucleotide sequence heterogeneity of an RNA phage population

Abstract

Gene

Anal. Biochem.

Gene

J. Mol. Biol.

J. Mol. Biol.

Enzyme polymorphisms in man

A molecular approach to the study of genic heterozygosity in natural populations. I. The number of alleles at different loci in Drosophila pseudoobscura

Genetics

Evolutionary rate at the molecular level

Nature

The rate of molecular evolution considered from the standpoint of population genetics