Climbing the vertebrate branch of U1A/U2B″ protein evolution.
In the vertebrate lineage of the U1A/U2B″/SNF protein family, the U1A and U2B″ proteins bind to RNA stem-loops in the U1 or U2 snRNPs, respectively. However, their specialization is fairly recent, as they evolved from a single ancestral protein. The progress of their specialization (subfunctionalization) can be monitored by the amino acid sequence changes that give rise to their modern RNA-binding specificity. Using ancestral sequence reconstruction to predict the intermediates on the evolutionary branch, a probable path of sequential changes is defined for U1A and U2B″. The RNA-binding affinity for U1A/U2B″ protein ancestors was measured using modern U1 and U2 snRNA stem-loops and RNA stem-loop variants to understand how the proteins' RNA specificities evolved.
Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St. Louis, Missouri 63110, USA.
Kimberly J
KJ
Delaney
Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St. Louis, Missouri 63110, USA.
Sandra G
SG
Williams
Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St. Louis, Missouri 63110, USA.
Mariah
M
Lawler
Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St. Louis, Missouri 63110, USA.
Kathleen B
KB
Hall
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019143:Evolution, Molecular; D049810:Genetic Speciation; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D017412:Ribonucleoprotein, U1 Small Nuclear / Q000737:chemistry / Q000235:genetics*; D017413:Ribonucleoprotein, U2 Small Nuclear / Q000737:chemistry / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D014714:Vertebrates / Q000145:classification / Q000235:genetics*; D055517:snRNP Core Proteins / Q000737:chemistry / Q000235:genetics
D017412:Ribonucleoprotein, U1 Small Nuclear; D017413:Ribonucleoprotein, U2 Small Nuclear; C526408:SNRPB2 protein, human; C075339:U1A protein; D055517:snRNP Core Proteins
RRM; RRM:RNA binding; U1A; ancestral reconstruction; snRNP