genetically modified tomato

Tomatoes have been used as a model organism to study the fruit ripening of climacteric fruit. To understand the mechanisms involved in the process of ripening, scientists have genetically engineered tomatoes.{{cite journal|title=Ethylene biosynthesis and action in tomato: a model for climacteric fruit ripening |doi=10.1093/jxb/erf072 |date= October 2002|last1=Alexander|first1=L.|journal=Journal of Experimental Botany|volume=53|issue=377|pages=2039–55|pmid=12324528|last2=Grierson|first2=D|doi-access=free}}

In 1994, the Flavr Savr became the first commercially grown, genetically engineered food to be granted a license for human consumption. A second copy of the tomato gene for polygalacturonase was inserted into the tomato genome in the antisense direction.{{cite book|author=Redenbalpolollolneau, Matthew Kramer, Ray Sheehy, Rick Sanders, Cathy Houck and Don Emlay|year=1992|title=Safety Assessment of Genetically Engineered Fruits and Vegetables: A Case Study of the Flavr Savr Tomato|publisher=CRC Press|page=288}} The polygalacturonase enzyme degrades pectin, a component of the tomato cell wall, causing the fruit to soften. When the antisense gene is expressed, it interferes with the production of the polygalacturonase enzyme, delaying the ripening process. The Flavr Savr failed to achieve commercial success and was withdrawn from the market in 1997. Similar technology, but using a truncated version of the polygalacturonase gene, was used to make a tomato paste.

DNA Plant Technology (DNAP), Agritope, and Monsanto developed tomatoes that delayed ripening by preventing the production of ethylene, a hormone that triggers ripening of fruit.{{cite journal|author=Marcia Wood|title=Bioengineered Tomatoes Taste Great|date=July 1995|journal=Agricultural Research Magazine|url=http://www.ushrl.saa.ars.usda.gov/is/ar/archive/jul95/tomatoes0795.htm?pf=1|access-date=2010-08-20|archive-date=2012-11-19|archive-url=https://web.archive.org/web/20121119134311/http://www.ars.usda.gov/is/ar/archive/jul95/tomatoes0795.htm?pf=1|url-status=dead}} All three tomatoes inhibited ethylene production by reducing the amount of 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor to ethylene. DNAP's tomato, called Endless Summer, inserted a truncated version of the ACC synthase gene into the tomato that interfered with the endogenous ACC synthase.{{cite web|author=Center for Environmental Risk Assessment|title=GM Crop Database: Event 1345-4|publisher=International Life Sciences Institute|url=http://cera-gmc.org/index.php?action=gm_crop_database&mode=ShowProd&data=1345-4|archive-url=https://web.archive.org/web/20110529104842/http://cera-gmc.org/index.php?action=gm_crop_database&mode=ShowProd&data=1345-4|url-status=usurped|archive-date=May 29, 2011}} Monsanto's tomato was engineered with the ACC deaminase gene from the soil bacterium Pseudomonas chlororaphis that lowered ethylene levels by breaking down ACC.{{cite journal|doi=10.2307/3869226|journal=The Plant Cell|volume=3|issue=11|pages=1187–1193|title=Control of Ethylene Synthesis by Expression of a Bacterial Enzyme in Transgenic Tomato Plants|author1=H. J. Klee |author2=M. B. Hayford |author3=K. A. Kretzmer |author4=G. F. Barry |author5=G. M. Kishore |url=http://www.plantcell.org/cgi/content/abstract/3/11/1187|year=1991|jstor=3869226|pmid=1821764|pmc=160085|citeseerx=10.1.1.486.7205}} Agritope introduced an S-adenosylmethionine hydrolase (SAMase) encoding gene derived from the E. coli bacteriophage T3, which reduced the levels of S-adenosylmethionine, a precursor to ACC.{{Cite journal| volume = 26| journal = Plant Molecular Biology| title = Reduced ethylene synthesis by transgenic tomatoes expressing S-adenosylmethionine hydrolase | first6 = R. K.| issue = 3| pages = 781–790| doi = 10.1007/BF00028848| pmid = 7999994| year = 1994| last6 = Bestwick | first5 = W. | first2 = J. A.| last2 = Kellogg |first1 = X.| last3 = Wagoner | first3 = W.| last5 = Matsumura | first4 = D.| last4 = Langhoff| last1 = Good| s2cid = 12598469}} Endless Summer was briefly tested in the marketplace, but patent arguments forced its withdrawal.{{cite book|title=AP Environmental Science|author1=Craig Freudenrich|author2=Dora Barlaz|author3=Jane Gardner|publisher=Kaplen inc|year=2009|pages=189–190|url=https://books.google.com/books?id=gT7Saz64Bs4C&q=Endless+summer+tomato&pg=PA190|isbn=978-1-4277-9816-9}}{{Dead link|date=May 2024 |bot=InternetArchiveBot |fix-attempted=yes }}

Scientists in India have delayed the ripening of tomatoes by silencing two genes encoding N-glycoprotein-modifying enzymes, α-mannosidase and β-D-N-acetylhexosaminidase. The fruits produced were not visibly damaged after being stored at room temperature for 45 days, whereas unmodified tomatoes had gone rotten.{{Cite journal| issue = 6| volume = 107| journal = Proceedings of the National Academy of Sciences of the United States of America| title = Enhancement of fruit shelf life by suppressing N-glycan processing enzymes| pages = 2413–2418| year = 2010| doi = 10.1073/pnas.0909329107| pmc = 2823905| pmid = 20133661 | first6 = A.| last6 = Datta| last3 = Prabha | first2 = S.| last2 = Ghosh | first1 = V. | first3 = T.| last4 = Chakraborty | first5 = S.| last5 = Chakraborty | first4 = N.| last1 = Meli|bibcode = 2010PNAS..107.2413M | doi-access = free}} In India, where 30% of fruit is wasted before it reaches the market due to a lack of refrigeration and poor road infrastructure, the researchers hope genetic engineering of the tomato would decrease wastage.{{cite news|url=https://www.independent.co.uk/news/world/asia/indias-new-delicacy-a-45dayold-tomato-1893333.html |title=India's new delicacy: a 45-day-old tomato - Asia, World |work=The Independent |date=2010-02-09 |access-date=2010-08-21 | location=London | first=Andrew | last=Buncombe}}

Abiotic stresses such as frost, drought, and high soil salinity are limiting factors to the growth of tomatoes.{{Cite book| year = 2007| isbn = 978-1-4020-5577-5| doi = 10.1007/978-1-4020-5578-2_27| pages = 669–700| title = Advances in Molecular Breeding Toward Drought and Salt Tolerant Crops| first1 = M. R.| last1 = Foolad| chapter = Current Status of Breeding Tomatoes for Salt and Drought Tolerance}} While no genetically modified stress-tolerant plants are currently{{when|date=May 2022}} commercialised, transgenic approaches have been researched. An early tomato was developed that contained an antifreeze gene (afa3) from the winter flounder with the aim of increasing the tomato's tolerance to frost, which became an icon in the early years of the debate over genetically modified foods, especially in relation to the perceived ethical dilemma of combining genes from different species. This tomato gained the moniker "fish tomato".{{cite book|last=Mchugen|first=Alan|title=Pandora's Picnic Basket|url=https://books.google.com/books?id=UkAAZPNS9b4C&q=alan+mchughen+fish+tomato&pg=PA15 |year=2000|publisher=Oxford University Press, UK |isbn=978-0-19-850674-4}} The antifreeze protein was found to inhibit ice recrystallization in the flounder blood, but had no effect when expressed in transgenic tobacco.{{Cite journal| last1 = Lemaux | first1 = P.| title = Genetically Engineered Plants and Foods: A Scientist's Analysis of the Issues (Part I)| journal = Annual Review of Plant Biology| volume = 59| pages = 771–812| year = 2008| pmid = 18284373| doi = 10.1146/annurev.arplant.58.032806.103840}} The resulting tomato was never commercialized, possibly because the transgenic plant did not perform well in its frost-tolerance or other agronomic characteristics. Another failed cold tolerant is the E. coli GR transgenic: Others had successfully produced cold tolerant Nicotiana tabacum by inserting various enzymes into the plastids that had already been observed to be more active under cold stress in the donor organism. Brüggemann et al. 1999 thus assumed the same would hold for a transfer of E. coli{{'}}s glutathione reductase → the chloroplasts of S. lycopersicum and S. peruvianum. They overexpressed the donated GR {{endash}} and this was supplementing the endogenous GR. Although total GR activity was increased, no improvement in cold tolerance occurred.{{cite journal | last=Iba | first=Koh | title=Acclimative Response to Temperature Stress in Higher Plants: Approaches of Gene Engineering for Temperature Tolerance | journal=Annual Review of Plant Biology | publisher=Annual Reviews | volume=53 | issue=1 | year=2002 | issn=1543-5008 | doi=10.1146/annurev.arplant.53.100201.160729 | pages=225–245| pmid=12221974 }}

Other genes from various species have been inserted into the tomato with the hope of increasing their resistance to various environmental factors. A gene from rice (Osmyb4), which codes for a transcription factor, that was shown to increase cold and drought tolerance in transgenic Arabidopsis thaliana plants, was inserted into the tomato. This resulted in increased drought tolerance, but did not appear to have any effect on cold tolerance.{{Cite journal | last1 = Vannini | first1 = C. | last2 = Campa | first2 = M. | last3 = Iriti | first3 = M. | last4 = Genga | first4 = A. | last5 = Faoro | first5 = F. | last6 = Carravieri | first6 = S. | last7 = Rotino | first7 = G. L. | last8 = Rossoni | first8 = M. | last9 = Spinardi | first9 = A. | last10 = Bracale | first10 = M. | doi = 10.1016/j.plantsci.2007.05.007 | title = Evaluation of transgenic tomato plants ectopically expressing the rice Osmyb4 gene | journal = Plant Science | volume = 173 | issue = 2 | pages = 231–239 | year = 2007 }} Overexpressing a vacuolar Na⁺/H⁺ antiport (AtNHX1) from A. thaliana lead to salt accumulation in the leaves of the plants, but not in the fruit and allowed them to grow more in salt solutions than wildtype plants.{{Cite journal | last1 = Zhang | first1 = H. X. | last2 = Blumwald | first2 = E. | title = Transgenic salt-tolerant tomato plants accumulate salt in foliage but not in fruit | journal = Nature Biotechnology | volume = 19 | issue = 8 | pages = 765–768 | doi = 10.1038/90824 | year = 2001 | pmid = 11479571| s2cid = 1940765 }}{{cite web|url=https://www.newscientist.com/article/dn1092-gene-modified-tomato-revels-in-salty-soils/ |title=Gene-modified tomato revels in salty soils - 31 July 2001 |publisher=New Scientist |access-date=2010-08-23}} Tobacco osmotic genes overexpressed in tomatoes produced plants that held a higher water content than wildtype plants, increasing tolerance to drought and salt stress.{{Cite journal | last1 = Goel | first1 = D. | last2 = Singh | first2 = A. K. | last3 = Yadav | first3 = V. | last4 = Babbar | first4 = S. B. | last5 = Bansal | first5 = K. C. | title = Overexpression of osmotin gene confers tolerance to salt and drought stresses in transgenic tomato (Solanum lycopersicum L.) | doi = 10.1007/s00709-010-0158-0 | journal = Protoplasma | volume = 245 | issue = 1–4 | pages = 133–141 | year = 2010 | pmid = 20467880| s2cid = 21089935 }}

The insecticidal toxin from the bacterium Bacillus thuringiensis has been inserted into a tomato plant.{{Cite journal| last1 = Fischhoff | first1 = D. A.| last2 = Bowdish | first2 = K. S.| last3 = Perlak | first3 = F. J.| last4 = Marrone | first4 = P. G.| last5 = McCormick | first5 = S. M.| last6 = Niedermeyer | first6 = J. G.| last7 = Dean | first7 = D. A.| last8 = Kusano-Kretzmer | first8 = K.| last9 = Mayer | first9 = E. J.| last10 = Rochester | first10 = D. E.| last11 = Rogers | first11 = S. G.| last12 = Fraley | first12 = R. T.| title = Insect Tolerant Transgenic Tomato Plants| journal = Bio/Technology| volume = 5| pages = 807–813| year = 1987| doi = 10.1038/nbt0887-807 | issue=8| s2cid = 42628662}} When field tested, they showed resistance to the tobacco hornworm (Manduca sexta), tomato fruitworm (Heliothis zea), the tomato pinworm (Keiferia lycopersicella), and the tomato fruit borer (Helicoverpa armigera).{{cite journal | journal = Nature Biotechnology | volume = 7| last1 = Delannay | first1 = X. | issue = 12 | last2 = Lavallee | first2 = B. J. | last3 = Proksch | first3 = R. K. | last4 = Fuchs | first4 = R. L. | last5 = Sims | first5 = S. R. | last6 = Greenplate | first6 = J. T. | last7 = Marrone | first7 = P. G. | last8 = Dodson | first8 = R. B. | last9 = Augustine | first9 = J. J. | last10 = Layton | first10 = J. G. | last11 = Fischhoff | first11 = D. A. | title = Field Performance of Transgenic Tomato Plants Expressing the Bacillus Thuringiensis Var. Kurstaki Insect Control Protein | doi = 10.1038/nbt1289-1265 | year = 1989 | pages = 1265–1269 | s2cid = 41557045}}{{Cite journal| pages = 135–139| year = 2004| doi = 10.1016/j.cropro.2003.08.006| last1 = Kumar| volume = 23 | first1 = H.| last2 = Kumar | first2 = V.| title = Tomato expressing Cry1A(b) insecticidal protein from Bacillus thuringiensis protected against tomato fruit borer, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) damage in the laboratory, greenhouse and field| journal = Crop Protection| issue = 2}} A 91-day feeding trial in rats showed no adverse effects,{{Cite book| last1 = Noteborn | first1 = H. P. J. M.| last2 = Bienenmann-Ploum | first2 = M. E.| last3 = Van Den Berg | first3 = J. H. J.| last4 = Alink | first4 = G. M.| last5 = Zolla | first5 = L.| last6 = Reynaerts | first6 = A.| last7 = Pensa | first7 = M.| last8 = Kuiper | first8 = H. A.| chapter = Safety Assessment of theBacillus thuringiensisInsecticidal Crystal Protein CRYIA(b) Expressed in Transgenic Tomatoes| title = Safety Assessment of the Bacillus thuringiensis Insecticidal Crystal Protein CRYIA(b) Expressed in Transgenic Tomatoes| series = ACS Symposium Series| volume = 605| pages = 134| year = 1995| isbn = 978-0-8412-3320-1| doi = 10.1021/bk-1995-0605.ch012}} but the Bt tomato has never been commercialised. Tomatoes resistant to a root-knot nematode have been created by inserting a cysteine proteinase inhibitor gene from taro.{{Cite journal| volume = 29| journal = Plant Cell Reports| title = Heterologous expression of taro cystatin protects transgenic tomato against Meloidogyne incognita infection by means of interfering sex determination and suppressing gall formation| issue = 3| pages = 231–238| doi = 10.1007/s00299-009-0815-y| pmid = 20054551| year = 2010 | first5 = M.| last5 = Chan | first2 = A.| last2 = Yang | first1 = Y.| last3 = Chen | first3 = J. | first4 = K.| last4 = Yeh| last1 = Chan| s2cid = 11651958| url = http://ntur.lib.ntu.edu.tw/bitstream/246246/243272/-1/59.pdf}} A chemically synthesised cecropin B gene, usually found in the giant silk moth (Hyalophora cecropia), has been introduced into tomato plants and in vivo studies show significant resistance to bacterial wilt and bacterial spot.{{Cite journal| pages = 769–775| issue = 3| year = 2010| pmid = 19966019| doi = 10.1128/AEM.00698-09| pmc = 2813020| volume = 76| journal = Applied and Environmental Microbiology| last2 = Huang | first1 = P. | first2 = H.| last3 = Chen| title = Expression of a synthesized gene encoding cationic peptide cecropin B in transgenic tomato plants protects against bacterial diseases | first3 = H.| last1 = Jan| bibcode = 2010ApEnM..76..769J}} When the cell wall proteins, polygalacturonase and expansin are prevented from being produced in fruits, they are less susceptible to the fungus Botrytis cinerea than normal tomatoes.{{cite web|title=Fruit Cell Wall Proteins Help Fungus Turn Tomatoes From Ripe To Rotten|url=https://www.sciencedaily.com/releases/2008/01/080126172454.htm|publisher=Science Daily|access-date=29 August 2010|date=Jan 31, 2008}}{{Cite journal| last1 = Cantu | first1 = D.| last2 = Vicente | first2 = A.| last3 = Greve | first3 = L.| last4 = Dewey | first4 = F.| last5 = Bennett | first5 = A.| last6 = Labavitch | first6 = J.| last7 = Powell | first7 = A.| title = The intersection between cell wall disassembly, ripening, and fruit susceptibility to Botrytis cinerea| journal = Proceedings of the National Academy of Sciences of the United States of America| volume = 105| issue = 3| pages = 859–864| year = 2008| pmid = 18199833| pmc = 2242701| doi = 10.1073/pnas.0709813105|bibcode = 2008PNAS..105..859C | doi-access = free}} Pest-resistant tomatoes can reduce the ecological footprint of tomato production, while at the same time increase farm income.Groeneveld, Rolf, Erik Ansink, Clemens van de Wiel, and Justus Wesseler (2011) Benefits and costs of biologically contained GM tomatoes and eggplants in Italy and Spain. Sustainability. 2011, 3, 1265-1281

Tomatoes have been altered in attempts to add nutritional content. In 2000, the concentration of pro-vitamin A was increased by adding a bacterial gene encoding phytoene desaturase, although the total amount of carotenoids remained equal.{{Cite journal | last1 = Römer | first1 = S. | last2 = Fraser | first2 = P. D. | last3 = Kiano | first3 = J. W. | last4 = Shipton | first4 = C. A. | last5 = Misawa | first5 = N. | last6 = Schuch | first6 = W. | last7 = Bramley | first7 = P. M. | doi = 10.1038/76523 | title = Elevation of the provitamin a content of transgenic tomato plants | journal = Nature Biotechnology | volume = 18 | issue = 6 | pages = 666–669 | year = 2000 | pmid = 10835607| s2cid = 11801214 }} The researchers admitted at the time that it had no prospect of being grown commercially due to the anti-GM climate. Sue Meyer of the pressure group Genewatch, told The Independent that she believed, "If you change the basic biochemistry, you could alter the levels of other nutrients very important for health".{{cite news|url=https://www.independent.co.uk/news/science/no-market-for-the-gm-tomato-that-fights-cancer-716980.html |title=No market for the GM tomato that fights cancer - Science, News |work=The Independent |date=2000-05-31 |access-date=2010-08-23 | location=London | first=Steve | last=Connor}}{{dead link|date=August 2021|bot=medic}}{{cbignore|bot=medic}} More recently, scientists created blue tomatoes that have increased the production of anthocyanin, an antioxidant in tomatoes, in several ways. One group added a transcription factor for the production of anthocyanin from Arabidopsis thaliana{{Cite journal | last1 = Zuluaga | first1 = D. L. | last2 = Gonzali | first2 = S. | last3 = Loreti | first3 = E. | last4 = Pucciariello | first4 = C. | last5 = Degl'Innocenti | first5 = E. | last6 = Guidi | first6 = L. | last7 = Alpi | first7 = A. | last8 = Perata | first8 = P. | doi = 10.1071/FP08021 | title = Arabidopsis thaliana MYB75/PAP1transcription factor induces anthocyanin production in transgenic tomato plants | journal = Functional Plant Biology | volume = 35 | issue = 7 | pages = 606–618 | year = 2008 | pmid = 32688816}} whereas another used transcription factors from snapdragon (Antirrhinum).{{cite web|url=https://www.sciencedaily.com/releases/2008/10/081026150149.htm |title=Purple Tomatoes, Rich In Health-Protecting Anthocyanins, Developed With Help Of Snapdragons |publisher=Sciencedaily.com |date=2008-10-27 |access-date=2010-08-21}} When the snapdragon genes were used, the fruits had similar anthocyanin concentrations to blackberries and blueberries.{{Cite journal| last1 = Butelli | first1 = E.| last2 = Titta | first2 = L.| last3 = Giorgio | first3 = M.| last4 = Mock | first4 = H.| last5 = Matros | first5 = A.| last6 = Peterek | first6 = S.| last7 = Schijlen | first7 = E.| last8 = Hall | first8 = R.| last9 = Bovy | first9 = A.| last10 = Luo | first10 = J.| last11 = Martin | first11 = C.| title = Enrichment of tomato fruit with health-promoting anthocyanins by expression of select transcription factors| journal = Nature Biotechnology| volume = 26| issue = 11| pages = 1301–1308| year = 2008| pmid = 18953354| doi = 10.1038/nbt.1506| s2cid = 14895646}} The inventors of the GMO blue tomato using snapdragon genes, Jonathan Jones and Cathie Martin of the John Innes Centre, founded a company called Norfolk Plant SciencesNorfolk Plant Sciences [http://www.norfolkplantsciences.com/about-nps/ About Norfolk Plant Sciences] {{webarchive |url=https://web.archive.org/web/20160304071031/http://www.norfolkplantsciences.com/about-nps/ |date=March 4, 2016 }} to commercialize the blue tomato. They partnered with a company in Canada called New Energy Farms to grow a large crop of blue tomatoes, from which to create juice to test in clinical trials on the way to obtaining regulatory approval.Clive Cookson for the Financial Times. January 24, 2014 [http://www.ft.com/cms/s/0/5d12b152-8504-11e3-a793-00144feab7de.html Purple tomato juice from Canadian GM crop heads for trial in UK]John Innes Centre 25 January 2014 [https://www.jic.ac.uk/news/2014/01/gm-purple-tomatoes/# Press Release: Bumper harvest for GM purple tomatoes] {{Webarchive|url=https://web.archive.org/web/20140813225642/https://www.jic.ac.uk/news/2014/01/gm-purple-tomatoes/ |date=2014-08-13 }}

Another group has tried to increase the levels of isoflavone, known for its potential cancer-preventive properties, by introducing soybean isoflavone synthase into tomatoes.{{Cite journal | last1 = Shih | first1 = C. H. | last2 = Chen | first2 = Y. | last3 = Wang | first3 = M. | last4 = Chu | first4 = I. K. | last5 = Lo | first5 = C. | title = Accumulation of Isoflavone Genistin in Transgenic Tomato Plants Overexpressing a Soybean Isoflavone Synthase Gene | doi = 10.1021/jf800423u | journal = Journal of Agricultural and Food Chemistry | volume = 56 | issue = 14 | pages = 5655–5661 | year = 2008 | pmid = 18540614}}

In 2021, Japanese Sanatech Seed issued Sicilian Rouge High GABA tomato variety with increased gamma-aminobutyric acid levels.

When geraniol synthase from lemon basil (Ocimum basilicum) was expressed in tomato fruits under a fruit-specific promoter, 60% of untrained taste testers preferred the taste and smell of the transgenic tomatoes. The fruits contained around half the amount of lycopene.{{Cite journal | first9 = N. | last10 = Simon | first10 = J. E. | last11 = Pichersky | first11 = E. | last12 = Lewinsohn | first12 = E.| title = Enrichment of tomato flavor by diversion of the early plastidial terpenoid pathway| last9 = Dudai | first8 = E.| last8 = Fallik| journal = Nature Biotechnology| volume = 25| pmid = 17592476| doi = 10.1038/nbt1312| year = 2007| pages = 899–901| issue = 8 | first7 = B.| last7 = Carmona| last3 = Tadmor | first3 = Y. | first2 = Y.| last2 = Sitrit | first1 = R.| last4 = Iijima | first4 = Y. | first6 = E.| last6 = Bar | first5 = N.| last5 = Bilenko| last1 = Davidovich-Rikanati| s2cid = 17955604 }}

Tomatoes (along with potatoes, bananas, and other plants) are being investigated as vehicles for delivering edible vaccines. Clinical trials have been conducted on mice using tomatoes expressing antibodies or proteins that stimulate antibody production targeted to norovirus, hepatitis B, rabies, HIV, and respiratory syncytial viruses and anthrax bacteria .{{Cite journal | last1 = Goyal | first1 = R. | last2 = Ramachandran | first2 = R. | last3 = Goyal | first3 = P. | last4 = Sharma | first4 = V. | title = Edible vaccines: Current status and future | journal = Indian Journal of Medical Microbiology | volume = 25 | issue = 2 | pages = 93–102 | year = 2007 | pmid = 17582177 | doi = 10.1016/S0255-0857(21)02165-4| doi-access =free }} Korean scientists are looking at using the tomato to express a vaccine against Alzheimer's disease.{{Cite journal| last1 = Youm | first1 = J.| last2 = Jeon | first2 = J.| last3 = Kim | first3 = H.| last4 = Kim | first4 = Y.| last5 = Ko | first5 = K.| last6 = Joung | first6 = H.| last7 = Kim | first7 = H.| title = Transgenic tomatoes expressing human beta-amyloid for use as a vaccine against Alzheimer's disease| journal = Biotechnology Letters| volume = 30| issue = 10| pages = 1839–1845| year = 2008| pmid = 18604480| pmc = 2522325| doi = 10.1007/s10529-008-9759-5}} Hilary Koprowski, who was involved in the development of the polio vaccine, led a group of researchers in developing a tomato expressing a recombinant vaccine to SARS.{{Cite journal| volume = 102| journal = Proceedings of the National Academy of Sciences of the United States of America| title = Severe acute respiratory syndrome (SARS) S protein production in plants: development of recombinant vaccine | first7 = H.| issue = 25| pages = 9062–9067| doi = 10.1073/pnas.0503760102| pmc = 1157057| pmid = 15956182| year = 2005| last7 = Koprowski | first6 = R.| last3 = Andrianov | first2 = M.| last2 = Golovkin | first1 = N. | first3 = V.| last4 = Spitsin| last6 = Egolf | first5 = Y.| last5 = Smirnov | first4 = S.| last1 = Pogrebnyak|bibcode = 2005PNAS..102.9062P | doi-access = free}}

Tomatoes are used as a model organism in scientific research and are frequently genetically modified to further understanding of particular processes. They have been used as a model in map-based cloning, where transgenic plants must be created to prove that a gene has been successfully isolated.{{Cite journal | last1 = Wing | first1 = R. | last2 = Zhang | first2 = H. B. | last3 = Tanksley | first3 = S. | title = Map-based cloning in crop plants. Tomato as a model system: I. Genetic and physical mapping of jointless | doi = 10.1007/BF00283423 | journal = MGG Molecular & General Genetics | volume = 242 | issue = 6 | year = 1994 | pages = 681–688 | pmid = 7908716| s2cid = 22438380 }} A plant peptide hormone, systemin, was first identified in tomato plants and genetic modification has been used to demonstrate its function, by adding antisense genes to silence the native gene or by adding extra copies of the native gene.{{cite journal|pmc=47331 |title=Expression of an antisense prosystemin gene in tomato plants reduces resistance toward Manduca sexta larvae |date= September 1993|volume= 90|issue= 17|pmid= 11607423|last1= Orozco-Cardenas|first1= M|last2= McGurl|first2= B|last3= Ryan|first3= CA|pages= 8273–6|journal= Proceedings of the National Academy of Sciences of the United States of America |doi=10.1073/pnas.90.17.8273|bibcode = 1993PNAS...90.8273O |doi-access=free }}{{cite journal|pmc=44904 |title=Overexpression of the prosystemin gene in transgenic tomato plants generates a systemic signal that constitutively induces proteinase inhibitor synthesis |date= October 1994|volume= 91|issue= 21|pmid= 7937894|last1= McGurl|first1= B|last2= Orozco-Cardenas|first2= M|last3= Pearce|first3= G|last4= Ryan|first4= CA|pages= 9799–802|journal= Proceedings of the National Academy of Sciences of the United States of America|bibcode = 1994PNAS...91.9799M |doi = 10.1073/pnas.91.21.9799 |doi-access=free }}

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Category:Genetically modified organisms in agriculture

Category:Tomatoes