Navigation Links
Plant geneticists find veritas in vino
Date:12/18/2007

Viticulture, the growing of grapes (Vitis vinifera) chiefly to make wine, is an ancient form of agriculture, evidence of which has been found from the Neolithic and Early Bronze Ages. We have a detailed understanding of how nurture affects the qualities of a grape harvest leading to the concept of terroir (the range of local influences that carry over into a wine). The nature of the grapes themselves has been less well understood but our knowledge of this is substantially increased this week by the publication in the open-access journal PLoS ONE of a high quality draft genome sequence of a Pinot Noir grape by an Italian-based multinational consortium.

The genome of the grape is spread over 19 pairs of chromosomes and is around 504.6 megabases in length. The team of researchers, led by Dr Riccardo Velasco of the Istituto Agrario di San Michele all'Adige, used a shotgun sequencing approach, which has resulted in 10.7X coverage, 4.2X using pyrosequencing and 6.5X by Sanger sequencing. At the same time, the genome of the grape chloroplast was also sequenced and, remarkably, this was found to be identical to an independently determined sequence from a different strain of Pinot Noir that was published last year.

The grape, therefore, has a relatively small genome for a crop plant, similar to that of rice or poplar trees and much smaller than that of wheat or maize. Nevertheless, sequencing the genome was complicated by the degree of heterozygosity between pairs of chromosomes, some 11.2% of the sequence differing between homologous regions. There was so much variation, in fact, that Velasco describes it as like being in the presence of two genomes.

Moreover, the team discovered more than two million single nucleotide polymorphisms (individual letter changes in the grapes genetic blueprint) in 87% of the 29,585 identified genes. While this made sequencing the genome difficult, it now provides a massive library of inherent variation with which to investigate which genes influence which characteristics of the growing plant and in what ways. It is a treasure trove, says Brian Dilkes of the University of California, DavisGenomeCenter, as detailed a description of a plant genome sequence as I have seen in a first paper.

The genome can also provide clues to the evolution of grapes. Many plant genomes, especially those of crop plants, have been produced by at least one duplication of a smaller ancestral genome. Whether this was true for grapes had been controversial but this study clearly shows that ten of the 19 chromosomes resulted from a duplication that occurred shortly after the lineage of grapes diverged from that of the model plants Arabidopsis and poplar.

The breeding of grape vines is difficult because they take several years to grow to maturity and domesticated grapes tend to have very low fertility. For this reason, grapes are usually propagated by cuttings or graftings so that vineyards are filled with hundreds of thousands of genetically identical clones. This leaves grapes highly susceptible to the emergence of aggressive microrganisms, such as phyloxera, which devastated European grape production in the 19th and early 20th century, and powdery mildew, which continues to threaten American harvests to this day.

The Pinot Noir genome will provide an invaluable tool for creating grape varieties resistant to such diseases without altering the quality of the resulting wine. Velasco and his colleagues have identified a large number of genes related to diseaseresistance, 289 of which contain one or more SNPs. In spite of this, Pinot Noir remains susceptible to several fungi, bacteria and viruses possibly due to a defective system for recognition pathogen. Many of these disease-resistance genes are present in clusters whose associations with resistances or tolerances of different grape varieties to specific diseases can now be investigated. Also Pinot Noir can be crossed with many wild grapespecies providing a large reservoir of disease-resistancegenes, which can be exploited with the aid of this genome road map.

This description of the grape genome presents an opportunity to direct genetic improvement or disease resistance, says Brian Dilkes. The genome sequence simultaneously identified hundreds of genes, which correspond to enzymes that produce flavor and aroma compounds. This will allow breeding for diseases resistance to proceed without disturbing the biochemistry of taste and grape quality. When I told sommelier Andrew Meadows about this recently, his reaction was, Good! I would love to offer a decent Pinot for less than $30.

This grape genome may also have implications beyond viticulture. Grapes can be both genetically transformed and micropropogated to produce hundreds of identical clones. With the sequencing of its relatively small genome, it is well placed to become a model organism for fruit trees in general. It is, however, in the safeguarding and improvement of grape stocks that the effects of this genome will be felt most strongly. The sequence of the grape genome, says Velasco, together with the large arsenal of SNP loci, now offers a tool to open a new era in the molecular breeding of grapes.


'/>"/>

Contact: Rebecca Walton
rwalton@plos.org
44-122-346-3333
Public Library of Science
Source:Eurekalert

Related biology news :

1. Circadian clock controls plant growth hormone
2. Layered approach may yield stronger, more successful bone implants
3. Clearance of hepatitis C viral infection after liver transplantation
4. Device helps patients survive, regain function til transplant
5. How the plant immune system can drive the formation of new species
6. The American Society of Plant Biologists announces 2007 awards
7. UCR plant cell biologist to study how plant stem cells maintain and change their identity
8. A study proposes a new universal rule to explain the equilibrium of plant populations
9. A study proposes a new universal rule to explain the equilibrium of plant populations
10. Study shows vitamin C is essential for plant growth
11. Clever plants chat over their own network
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/31/2017)... CAMBRIDGE, Mass. , Jan. 31, 2017 /PRNewswire-USNewswire/ ... develop novel therapies for the treatment of bacterial ... generation set of antibacterial candidates from Pro Bono ... the increased prevalence of multi-drug resistant forms of ... by Cantab Anti Infectives Ltd, a PBB group ...
(Date:1/26/2017)... , Jan. 26, 2017  Acuity Market Intelligence ... Biometrics and Digital Identity".  Acuity characterizes 2017 as ... when increased adoption reflects a new understanding of ... "Biometrics and digital identity are often perceived ... Maxine Most , Principal of Acuity Market intelligence. ...
(Date:1/24/2017)... , Jan. 24, 2017  It sounds ... baby,s sock that monitors vital signs and alerts ... an infant,s oxygen saturation level drops. But pediatric ... alarm to parents, with no evidence of medical ... devices are marketed aggressively to parents of healthy ...
Breaking Biology News(10 mins):
(Date:2/23/2017)... , Feb. 23, 2017 /PRNewswire/ - The Fight ... for Cancer Research (OICR) are pleased to report that ... A financing, with Johnson & Johnson Innovation – JJDC, ... include venture groups HealthCap, TPG Biotechnology Partners, and Genesys ... ...
(Date:2/23/2017)... Atlanta, it seems everyone has a chance to express their ... expressive and dynamic community unlike any other. The businesses that ... With their newest salon in ... on that tradition with a unique, fresh approach to head ... the newest of 13 nationwide locations, each of them well-situated ...
(Date:2/23/2017)... 2017  Imanis Life Sciences announced today the ... vaccinia viruses for virotherapy research. These viruses are ... proprietary, vaccinia virus-based technology platform for research use. ... a partnership with Genelux to offer researchers, for ... use in research," said Dr. Kah Whye ...
(Date:2/23/2017)... (PRWEB) , ... February 23, ... ... Inc., announced today that in a published evaluation of multiple immunoassay-based threat ... U.S. Department of Energy Laboratory, PathSensors’ CANARY® biosensor threat detection technology was ...
Breaking Biology Technology: