Analysis of BAC-end sequences in common bean (Phaseolus vulgaris L.) towards the development and characterization of long motifs SSRs

Plant Mol Biol. 2014 Nov;86(4-5):455-70. doi: 10.1007/s11103-014-0240-7. Epub 2014 Aug 28.

Abstract

The increasing volume of genomic data on the Phaseolus vulgaris species have contributed to its importance as a model genetic species and positively affected the investigation of other legumes of scientific and economic value. To expand and gain a more in-depth knowledge of the common bean genome, the ends of a number of bacterial artificial chromosome (BAC) were sequenced, annotated and the presence of repetitive sequences was determined. In total, 52,270 BESs (BAC-end sequences), equivalent to 32 Mbp (~6 %) of the genome, were processed. In total, 3,789 BES-SSRs were identified, with a distribution of one SSR (simple sequence repeat) per 8.36 kbp and 2,000 were suitable for the development of SSRs, of which 194 were evaluated in low-resolution screening. From 40 BES-SSRs based on long motifs SSRs (≥ trinucleotides) analyzed in high-resolution genotyping, 34 showed an equally good amplification for the Andean and for the Mesoamerican genepools, exhibiting an average gene diversity (H E) of 0.490 and 5.59 alleles/locus, of which six classified as Class I showed a H E ≥ 0.7. The PCoA and structure analysis allowed to discriminate the gene pools (K = 2, FST = 0.733). From the 52,270 BESs, 2 % corresponded to transcription factors and 3 % to transposable elements. Putative functions for 24,321 BESs were identified and for 19,363 were assigned functional categories (gene ontology). This study identified highly polymorphic BES-SSRs containing tri- to hexanucleotides motifs and bringing together relevant genetic characteristics useful for breeding programs. Additionally, the BESs were incorporated into the international genome-sequencing project for the common bean.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Chromosomes, Artificial, Bacterial / genetics*
  • DNA, Plant / chemistry
  • DNA, Plant / genetics*
  • Genetic Variation
  • Genome, Plant / genetics
  • Genomic Library
  • Genotype
  • Microsatellite Repeats / genetics*
  • Phaseolus / genetics*
  • Polymorphism, Genetic
  • Sequence Analysis, DNA

Substances

  • DNA, Plant