title: Efficient targeting of plant disease resistance loci using NBS profiling.
abstract: The conserved sequences in the nucleotide-binding sites of the nucleotide-binding site-leucine-rich repeat (NBS-LRR) class of disease resistance (R) genes have been used for PCR-based R-gene isolation and subsequent development of molecular markers. Here we present a PCR-based approach (NBS profiling) that efficiently targets R genes and R-gene analogs (RGAs) and, at the same time, produces polymorphic markers in these genes. In NBS profiling, genomic DNA is digested with a restriction enzyme, and an NBS-specific (degenerate) primer is used in a PCR reaction towards an adapter linked to the resulting DNA fragments. The NBS profiling protocol generates a reproducible polymorphic multilocus marker profile on a sequencing gel that is highly enriched for R genes and RGAs. NBS profiling was successfully used in potato with several restriction enzymes, and several primers targeted to different conserved motifs in the NBS. Across primers and enzymes, the NBS profiles contained 50-90% fragments that were significantly similar to known R-gene and RGA sequences. The protocol was similarly successful in other crops (including tomato, barley, and lettuce) without modifications. NBS profiling can thus be used to produce markers tightly linked to R genes and R-gene clusters for genomic mapping and positional cloning and to mine for new alleles and new sources of disease resistance in available germplasm.
authors.affiliation: Plant Research International B.V., Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands. gerard.vanderlinden@wur.nl
authors.forename: C Gerard
authors.initials: CG
authors.lastname: van der Linden
authors.forename: Doret C A E
authors.initials: DC
authors.lastname: Wouters
authors.forename: Virag
authors.initials: V
authors.lastname: Mihalka
authors.forename: Elena Z
authors.initials: EZ
authors.lastname: Kochieva
authors.forename: Marinus J M
authors.initials: MJ
authors.lastname: Smulders
authors.forename: Ben
authors.initials: B
authors.lastname: Vosman
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D018556:Crops, Agricultural / Q000235:genetics*; D017931:DNA Primers; D007113:Immunity, Innate / Q000235:genetics*; D007930:Leucine; D008969:Molecular Sequence Data; D009711:Nucleotides / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011110:Polymorphism, Genetic; D020449:Repetitive Sequences, Amino Acid / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D009711:Nucleotides; D007930:Leucine