Association of intron phases with conservation at splice site sequences and evolution of spliceosomal introns.

How exon-intron structures of eukaryotic genes evolved under various evolutionary forces remains unknown. The phases of spliceosomal introns (the placement of introns with respect to reading frame) provide an opportunity to approach this question. When a large number of nuclear introns in protein-coding genes were analyzed, it was found that most introns were of phase 0, which keeps codons intact. We found that the phase distribution of spliceosomal introns is strongly correlated with the sequence conservation of splice signals in exons; the relatively underrepresented phase 2 introns are associated with the lowest conservation, the relatively overrepresented phase 0 introns display the highest conservation, and phase 1 introns are intermediate. Given the detrimental effect of mutations in exon sequences near splice sites as found in molecular experiments, the underrepresentation of phase 2 introns may be the result of deleterious-mutation-driven intron loss, suggesting a possible genetic mechanism for the evolution of intron-exon structures.

[1]  A. Newman,et al.  Evidence that introns arose at proto‐splice sites. , 1989, The EMBO journal.

[2]  J. Gillespie The causes of molecular evolution , 1991 .

[3]  J D Palmer,et al.  Intron "sliding" and the diversity of intron positions. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[4]  A. Krainer,et al.  Mechanisms for selecting 5' splice sites in mammalian pre-mRNA splicing. , 1994, Trends in genetics : TIG.

[5]  W. Pearson Effective protein sequence comparison. , 1996, Methods in enzymology.

[6]  T. D. Schneider,et al.  Information content of binding sites on nucleotide sequences. , 1986, Journal of molecular biology.

[7]  Tom Maniatis,et al.  A single-base change at a splice site in a β0-thalassemic gene causes abnormal RNA splicing , 1982, Cell.

[8]  M. Long,et al.  Intron-exon structures: From molecular to population biology , 1998 .

[9]  T. Jukes,et al.  The neutral theory of molecular evolution. , 2000, Genetics.

[10]  Arlin Stoltzfus,et al.  Molecular evolution: Recent cases of spliceosomal intron gain? , 1998, Current Biology.

[11]  Leland T. Blank,et al.  Statistical Procedures for Engineering, Management, and Science , 1980 .

[12]  R. Reed,et al.  Initial splice-site recognition and pairing during pre-mRNA splicing. , 1996, Current opinion in genetics & development.

[13]  John M Logsdon,et al.  The recent origins of introns , 1992, Current Biology.

[14]  D. Charlesworth,et al.  The evolution of the alcohol dehydrogenase gene family by loss of introns in plants of the genus Leavenworthia (Brassicaceae). , 1998, Molecular biology and evolution.

[15]  J. Steitz,et al.  The U5 and U6 small nuclear RNAs as active site components of the spliceosome. , 1993, Science.

[16]  S J de Souza,et al.  Relationship between "proto-splice sites" and intron phases: evidence from dicodon analysis. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[17]  T. D. Schneider,et al.  Features of spliceosome evolution and function inferred from an analysis of the information at human splice sites. , 1992, Journal of molecular biology.

[18]  P. Sharp Speculations on RNA splicing , 1981, Cell.

[19]  S J de Souza,et al.  Toward a resolution of the introns early/late debate: only phase zero introns are correlated with the structure of ancient proteins. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[20]  R. Padgett,et al.  Conserved sequences in a class of rare eukaryotic nuclear introns with non-consensus splice sites. , 1994, Journal of molecular biology.

[21]  R. O’Neill,et al.  De novo insertion of an intron into the mammalian sex determining gene, SRY. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[22]  T. D. Schneider,et al.  Theory of molecular machines. II. Energy dissipation from molecular machines. , 1991, Journal of theoretical biology.

[23]  John M. Logsdon,et al.  The recent origins of introns. , 1991 .

[24]  Stephen M. Mount,et al.  A catalogue of splice junction sequences. , 1982, Nucleic acids research.

[25]  W. Gilbert,et al.  The exon theory of genes. , 1987, Cold Spring Harbor symposia on quantitative biology.

[26]  Stuart H. Orkin,et al.  Abnormal RNA splicing causes one form of α thalassemia , 1982, Cell.

[27]  C. Norman,et al.  Mutations in yeast U5 snRNA alter the specificity of 5′ splice-site cleavage , 1991, Cell.

[28]  R. Greenberg Biometry , 1969, The Yale Journal of Biology and Medicine.

[29]  G. M. Suboch,et al.  Analysis of nonuniformity in intron phase distribution. , 1992, Nucleic acids research.

[30]  W. Gilbert,et al.  Intron phase correlations and the evolution of the intron/exon structure of genes. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[31]  M. Giroux,et al.  De novo synthesis of an intron by the maize transposable element Dissociation. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[32]  Hiroshi Akashi,et al.  Molecular Evidence for Natural Selection , 1995 .

[33]  J. Logsdon,et al.  The recent origins of spliceosomal introns revisited. , 1998, Current opinion in genetics & development.

[34]  W. Gilbert,et al.  Introns and gene evolution , 1996, Genes to cells : devoted to molecular & cellular mechanisms.

[35]  M Tomita,et al.  Introns and reading frames: correlation between splicing sites and their codon positions. , 1996, Molecular biology and evolution.

[36]  T. D. Schneider,et al.  Sequence logos: a new way to display consensus sequences. , 1990, Nucleic acids research.

[37]  J. Steitz,et al.  Site-specific cross-linking of mammalian U5 snRNP to the 5' splice site before the first step of pre-mRNA splicing. , 1992, Genes & development.

[38]  S J de Souza,et al.  Evolution of the intron-exon structure of eukaryotic genes. , 1995, Current opinion in genetics & development.

[39]  J. Steitz,et al.  Pre-mRNA splicing: the discovery of a new spliceosome doubles the challenge. , 1997, Trends in biochemical sciences.

[40]  G. Fichant Constraints acting on the exon positions of the splice site sequences and local amino acid composition of the protein. , 1992, Human molecular genetics.

[41]  W. Gilbert,et al.  The Yeast Splice Site Revisited: New Exon Consensus from Genomic Analysis , 1997, Cell.

[42]  G. Fink,et al.  Pseudogenes in yeast? , 1987, Cell.

[43]  S J de Souza,et al.  Origin of genes. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[44]  J. Steitz,et al.  A mammalian gene with introns instead of exons generating stable RNA products , 1996, Nature.

[45]  M. Aebi,et al.  Sequence requirements for splicing of higher eukaryotic nuclear pre-mRNA , 1986, Cell.

[46]  B. Séraphin,et al.  Exon mutations uncouple 5′ splice site selection from U1 snRNA pairing , 1990, Cell.