Characterization and utilization of a BAC library from artichoke

The globe artichoke (Cynara cardunculus var. scolymus; n=x=17 and genome size of ~1.08 Gbp/1C) is a member of the Asteraceae family that contributes significantly to the agricultural economy of the Mediterranean basin. Despite its commercial importance, relatively little is known about its genome. Here, we report on the characterization of a bacterial artificial chromosome (BAC) library of artichoke and the preliminary effort to integrate the artichoke linkage groups with specific chromosomes. The artichoke BAC library consisted of 57,600 clones, representing approximately 5 haploid genome equivalents. We employed a multidimensional BAC pooling strategy for PCR-screening. The BAC-pools were screened with various PCR-based markers, including map-anchored SSR markers and other PCR-markers for genes most of which involved in the biosynthesis of phenylpropanoids. Marker screening was carried out by using High Resolution Melt (HRM) analysis on BAC library pools. We identified some 50 BAC clones, and their sequencing is in progress. In addition, to provide a cytogenetic map of the artichoke genome, we are localizing these map-anchored BACs onto the artichoke chromosomes using FISH (fluorescence in situ hybridization). This artichoke BAC library will serve as an important resource to build an artichoke physical map, integrate the available linkage data to specific chromosomes and for comparative genome analyses.