Abstract
Four closely related species of yeast possess multicopy nuclear plasmids whose shared molecular architecture demonstrates a common ancestor, despite their lack of discernible DNA sequence homology. Each plasmid encodes three proteins which have equivalent essential functions in plasmid maintenance. These three groups of proteins show markedly different degrees of conservation, so that although we have successfully aligned sequences for two groups, members of the third group have diverged to such an extent that they cannot be aligned. All the proteins are sufficiently different that they function only in conjunction with their encoding plasmid. These proteins have therefore conserved their functional interactions with the relevant DNA sequences of their particular plasmids, despite lack of amino acid sequence conservation. The maintenance of function in the face of DNA sequence divergence is analagous to the coevolution of ribosomal DNA promoters and RNA polymerase I, and suggests that molecular drive may be an important force in the evolution of these plasmids. This view is reinforced by the inconsistent phylogenetic relationships determined from the two alignment sets, and by the contradiction that the two plasmids known to be the closest related taxonomically and by their host interchangeability are suggested to be the most distant by their sequences.
| Original language | English |
|---|---|
| Pages (from-to) | 601-607 |
| Number of pages | 7 |
| Journal | Journal of Molecular Biology |
| Volume | 200 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - Apr 5 1988 |
Fingerprint
ASJC Scopus subject areas
- Virology
Cite this
Unexpected divergence and molecular coevolution in yeast plasmids. / Murray, James A H; Cesareni, Gianni; Argos, Patrick.
In: Journal of Molecular Biology, Vol. 200, No. 3, 05.04.1988, p. 601-607.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Unexpected divergence and molecular coevolution in yeast plasmids
AU - Murray, James A H
AU - Cesareni, Gianni
AU - Argos, Patrick
PY - 1988/4/5
Y1 - 1988/4/5
N2 - Four closely related species of yeast possess multicopy nuclear plasmids whose shared molecular architecture demonstrates a common ancestor, despite their lack of discernible DNA sequence homology. Each plasmid encodes three proteins which have equivalent essential functions in plasmid maintenance. These three groups of proteins show markedly different degrees of conservation, so that although we have successfully aligned sequences for two groups, members of the third group have diverged to such an extent that they cannot be aligned. All the proteins are sufficiently different that they function only in conjunction with their encoding plasmid. These proteins have therefore conserved their functional interactions with the relevant DNA sequences of their particular plasmids, despite lack of amino acid sequence conservation. The maintenance of function in the face of DNA sequence divergence is analagous to the coevolution of ribosomal DNA promoters and RNA polymerase I, and suggests that molecular drive may be an important force in the evolution of these plasmids. This view is reinforced by the inconsistent phylogenetic relationships determined from the two alignment sets, and by the contradiction that the two plasmids known to be the closest related taxonomically and by their host interchangeability are suggested to be the most distant by their sequences.
AB - Four closely related species of yeast possess multicopy nuclear plasmids whose shared molecular architecture demonstrates a common ancestor, despite their lack of discernible DNA sequence homology. Each plasmid encodes three proteins which have equivalent essential functions in plasmid maintenance. These three groups of proteins show markedly different degrees of conservation, so that although we have successfully aligned sequences for two groups, members of the third group have diverged to such an extent that they cannot be aligned. All the proteins are sufficiently different that they function only in conjunction with their encoding plasmid. These proteins have therefore conserved their functional interactions with the relevant DNA sequences of their particular plasmids, despite lack of amino acid sequence conservation. The maintenance of function in the face of DNA sequence divergence is analagous to the coevolution of ribosomal DNA promoters and RNA polymerase I, and suggests that molecular drive may be an important force in the evolution of these plasmids. This view is reinforced by the inconsistent phylogenetic relationships determined from the two alignment sets, and by the contradiction that the two plasmids known to be the closest related taxonomically and by their host interchangeability are suggested to be the most distant by their sequences.
UR - http://www.scopus.com/inward/record.url?scp=0024278448&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024278448&partnerID=8YFLogxK
U2 - 10.1016/0022-2836(88)90546-3
DO - 10.1016/0022-2836(88)90546-3
M3 - Article
C2 - 3294423
AN - SCOPUS:0024278448
VL - 200
SP - 601
EP - 607
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
SN - 0022-2836
IS - 3
ER -