Common wheat (Triticum aestivum L., 2n = 6x = 42) is a polyploid species possessing one of the largest genomes among the cultivated crops (1C is approximately 17 000 Mb). The presence of three homoeologous genomes (A, B and D), and the prevalence of repetitive DNA make sequencing the wheat genome a daunting task. We have developed a novel 'chromosome arm-based' strategy for wheat genome sequencing to simplify this task; this relies on sub-genomic libraries of large DNA inserts. In this paper, we used a di-telosomic line of wheat to isolate six million copies of the short arm of chromosome 1B (1BS) by flow sorting. Chromosomal DNA was partially digested with HindIII and used to construct an arm-specific BAC library. The library consists of 65 280 clones with an average insert size of 82 kb. Almost half of the library (45%) has inserts larger than 100 kb, while 18% of the inserts range in size between 75 and 100 kb, and 37% are shorter than 75 kb. We estimated the chromosome arm coverage to be 14.5-fold, giving a 99.9% probability of identifying a clone corresponding to any sequence on the short arm of 1B. Each chromosome arm in wheat can be flow sorted from an appropriate cytogenetic stock, and we envisage that the availability of chromosome arm-specific BAC resources in wheat will greatly facilitate the development of ready-to-sequence physical maps and map-based gene cloning.

Laboratory of Molecular Cytogenetics and Cytometry Institute of Experimental Botany Sokolovská 6 CZ 77200 Olomouc Czech Republic

Citace poskytuje Crossref.org

Flow Cytometric Analysis and Sorting of Plant Chromosomes

Chromosome identification for the carnivorous plant Genlisea margaretae

BioNano genome mapping of individual chromosomes supports physical mapping and sequence assembly in complex plant genomes

A high-resolution physical map integrating an anchored chromosome with the BAC physical maps of wheat chromosome 6B

Mapping nonrecombining regions in barley using multicolor FISH

Chromosomes in the flow to simplify genome analysis

BAC libraries from wheat chromosome 7D: efficient tool for positional cloning of aphid resistance genes

Integration of genetic and physical maps of the chickpea (Cicer arietinum L.) genome using flow-sorted chromosomes

Coupling amplified DNA from flow-sorted chromosomes to high-density SNP mapping in barley

A novel resource for genomics of Triticeae: BAC library specific for the short arm of rye (Secale cereale L.) chromosome 1R (1RS)

Chromosome-based genomics in the cereals