Washington, Feb 26 : For the first time, scientists have given a proper insight into the DNA of the pea, by unravelling its genetic coding.
Researchers from the INRA Plant Genomics Research Unit at Evry, and the INRA Grain Legumes Research Unit at Bretenieres, both in France, discovered the first high-throughput forward and reverse genetics tool for the pea (Pisum sativum).
They say that their finding could have major benefits for crop breeders around the world.
The French scientists have developed a technique that has produced the most detailed reference collection of pea plant mutations yet assembled.
Abdelhafid Bendahmane and colleagues used plants from an early-flowering garden pea cultivar, Cameor, to create a mutant population, which they then systematically phenotyped for use in both forward and reverse genetics studies.
The team set up a pea TILLING (Targeting Induced Local Lesions IN Genomes) platform with DNA samples from 4,704 plants. The TILLING technique overcomes the pea's natural unsuitability to genetic modification techniques, and provides a powerful tool for investigating the role of essential genes.
This new tool has implications for both basic science and for crop improvement. TILLING is an alternative to Agrobacterium-based techniques, and uses EMS (ethane methyl sulfonate) mutagenesis coupled with a gene-specific detection of single-nucleotide mutations. This reverse genetic strategy can be applied to all types of organisms and can be automated for high-throughput approaches.
Following this study, the researchers created a database called UTILLdb, which described each mutant plant at different developmental stages, (from seedling through to fruit maturation), and also incorporates digital images of the plants. UTILLdb contains phenotypic as well as sequence information on mutant genes, and can be searched for TILLING alleles of genes of interest, using the 'BLAST' tool, and for plant traits of interest, using keyword searches.
The results, according to the resarchers, will provide a powerful tool with which to investigate the genetics of peas and other legumes.
This will also assist efforts to produce new varieties of pea, both by genetic engineering and by conventional breeding.
"By opening [this database] to the community, we hope to fulfil the expectations of both crop breeders and scientists who are using the pea as their model of study," said Bendahmane.
The study is published in the journal Genome Biology.