Toward a resolution of the introns early/late debate: Only phase zero introns are correlated with the structure of ancient proteins

• DOI: 10.1073/pnas.95.9.5094
• Publication Date: 2002-07-26T14:31:39Z
• Authors: Sandro J. de Souza; Manyuan Long; Robert J. Klein; Scott Roy; Shin Lin; Walter Gilbert
• Keywords: Exon shuffling; Group II intron

We present evidence that a well defined subset of intron positions shows non-random distribution in ancient genes. analyze database conserved regions drawn from GenBank 101 to retest two predictions the theory first genes were constructed by exon shuffling. These are there should be an excess symmetric exons (and sets exons) flanked introns same phase (positions within codon) and proteins correlate with boundaries compact protein modules. Both these supported data, considerable statistical force ( P values < 0.0001). Intron modules diameters around 21, 27, 33 Å, this correlation is due zero introns. suggest 30–40% day correspond originally progenote, while almost all remaining added, or moved, appearing equally three phases. This proposal provides resolution for many arguments introns-early/introns-late debate.