The Secretary, Department of Biotechnology Shri M K Bhan today announced a major leap forward in the field of Biotechnology Research. Mr. Bhan informed the media persons in New Delhi that the Tomato Genome Consortium (TGC), a group of over 300 scientists from fourteen countries, has sequenced the genomes of the domesticated tomato and its wild ancestor, Solanum pimpinellifolium. This achievement is expected to lower costs and speed up efforts to improve the worldwide tomato production, making it better equipped to combat the pests, pathogens, drought and diseases that now plague growers. The work may also speed up improvements in other crops. This important result is published in this week’s issue of Nature as cover story.
Main contributor Director of National Institute of Plant Genome Research Prof. Akhilesh Kumar Tyagi said that India contributed sequence of euchromatic region with emphasis on chromosome 5 of tomato and provided support to generate 5-fold sequence coverage of the entire tomato genome by Next Generation Sequence (NGS) technology. Indian Team also participated in performing annotation of all predicted proteins using international databases as a part of the International Tomato Annotation Group (ITAG). Simultaneously, Indian researchers have taken up analysis of specific genes/gene families related to ripening, nutrition, disease resistance and abiotic stress tolerance based on transcriptome data and comparative genomics. The genomic resources generated are expected to greatly accelerate improvement of tomato by functional genomics and molecular breeding. The University of Delhi South Campus (Principal Investigator- J.P. Khurana), National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute (Principal Investigator- N.K. Singh), and National Institute of Plant Genome Research (Principal Investigator- D. Chattopadhyay), New Delhi, under the auspices of the Indian Initiative on Tomato Genome Sequencing (IITGS; Coordinator- A.K. Tyagi) participated in the international Tomato Genome Consortium (TGC). The Indian initiative was funded by the Department of Biotechnology, Government of India, and supported by the Indian Council for Agricultural Research.
Mr. Tyagi mentioned that the sequences provide a detailed overview at the functional portions of the tomato genome and its closest relative, revealing the order, orientation, types and relative positions of their 35,000 genes. The sequences will help researchers decipher the relationships between tomato genes and traits and broaden their understanding of genetic and environmental factors that interact to determine a field crop’s health and viability. Tomato is a member of the Solanaceae or nightshade family, and the new sequences are expected to provide reference points helpful for identifying important genes in tomato’s relatives. The group includes potato, pepper, eggplant and petunia and is the world’s most important vegetable plant family in terms of both economic value and production volume. Solanaceae members serve as sources of food, spices, medicines and ornamentals.
Elaborating further the Director of NIPGR Mr. Tyagi mentioned that the sequences also offer insight into how the tomato has diversified and adapted to new environments. They show that the tomato genome expanded abruptly about 60 million years ago, at a time close to one of the large mass extinctions. Subsequently, most of this genetic redundancy was lost. Some of the genes evolved during that event survive till today and control some of the most appealing traits of tomato.
Mr. Bhan said that the previous efforts have led to the sequencing of a number of other crop plants, including rice, corn, sorghum, poplar, potato, soybean, grape and Arabidopsis thaliana, a plant widely studied as a model organism. The availability of tomato genome sequence will not only serve as a reference for other Solanaceous species but also help in comparative genomics among diverse taxa.
TGC was established as a result of a scientific conference organized in 2003 in Washington, DC. Consortium members include scientists from Argentina, Belgium, China, France, Germany, India, Israel, Italy, Japan, Korea, Spain, the Netherlands, the United Kingdom and the United States.
The genome sequence and related resources can be accessed at the Solgenomics website (http://solgenomics.net) and at http://mips.helmholtz-muenchen.de/plant/tomato/index.jsp