Beat Keller | |
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Born | |
Known for | disease resistance in cereals, wheat genome sequencing |
Scientific career | |
Fields | molecular biology, botany, wheat |
Institutions | University of Zurich |
Beat Keller (born September 14 1958 in Interlaken) is a Swiss molecular biologist and professor of plant molecular biology at the University of Zurich. He is known for his research on disease resistance in cereals.
Keller studied biology at the University of Basel from 1978 to 1982. His dissertation dealt with shape-determining proteins of the bacteriophage capsid T4: The role of gene products 67 and 68. In 1985 he began a postdoctoral fellowship at the Biozentrum of the University of Basel. In 1986, he continued his training as a molecular biologist with an EMBO Longterm Fellowship at the Salk Institute for Biological Studies in San Diego, where he worked in the plant biology research group of Christopher John Lamb. In 1989, Keller returned to Switzerland and founded a plant biotechnology group at the Swiss Federal Research Station for Agronomy (today Agroscope). The group, which specialized in cereal genetics, disease resistance and molecular markers, was headed by Keller until 1997. In 1995, he became a lecturer at ETH Zurich and in 1997 accepted an appointment as Professor of Molecular Plant Biology at the University of Zurich. From 1997 to 2014, he was Director of the Institute of Plant Biology at the University of Zurich and from 2002 to 2006 and from 2016 to 2018 Chairman of the Department of Biology. [1] From 2000 to 2006, Keller was Vice President of the Swiss Academy of Sciences (SCNAT) and is codirector of the research program "Evolution in Action". [2] From 2014 to 2022, he was a member of the Research Council of the Swiss National Science Foundation. [3] He is a member of the National Academy of Agricultural Sciences, India, and was admitted as a member of the section Agricultural and Nutritional Sciences of the German National Academy of Sciences Leopoldina on June 23, 2015.
Beat Keller's research focuses on the molecular basis of disease resistance in the cereals wheat, maize, barley and rye. This involves characterizing genes that are responsible for the formation of specific immune receptors. This included the isolation of the first resistance genes against fungal diseases in wheat [4] [5] and against leaf spot disease in maize. [6] In 2021, novel resistance genes were identified in wheat against powdery mildew and wheat leaf rust. [7] [8] [9] In addition, an important quantitative resistance gene, Lr34, was isolated, which is used intensively in wheat cultivation worldwide and has a novel resistance mechanism. [10] [11] Modified resistance genes were tested in field trials (www.protectedsite.ch) in transgenic wheat and barley plants. [12]
In complementary research directions, the molecular mechanisms of the evolution of the powdery mildew pathogen in its adaptation to new host species were identified and the molecules of the pathogen recognized by immune receptors were characterized. [13] [14] [15] [16] [17] The work on the wheat genome within the framework of the International Wheat Genome Sequencing Consortium [18] led to the production of the first high-quality wheat genome sequence. [19]
Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus Triticum ; the most widely grown is common wheat. The archaeological record suggests that wheat was first cultivated in the regions of the Fertile Crescent around 9600 BC. Botanically, the wheat kernel is a caryopsis, a type of fruit.
Arabidopsis thaliana, the thale cress, mouse-ear cress or arabidopsis, is a small plant from the mustard family (Brassicaceae), native to Eurasia and Africa. Commonly found along the shoulders of roads and in disturbed land, it is generally considered a weed.
Powdery mildew is a fungal disease that affects a wide range of plants. Powdery mildew diseases are caused by many different species of ascomycete fungi in the order Erysiphales. Powdery mildew is one of the easier plant diseases to identify, as the signs of the causal pathogen are quite distinctive. Infected plants display white powdery spots on the leaves and stems. This mycelial layer may quickly spread to cover all of the leaves. The lower leaves are the most affected, but the mildew can appear on any above-ground part of the plant. As the disease progresses, the spots get larger and denser as large numbers of asexual spores are formed, and the mildew may spread up and down the length of the plant.
Magnaporthe grisea, also known as rice blast fungus, rice rotten neck, rice seedling blight, blast of rice, oval leaf spot of graminea, pitting disease, ryegrass blast, Johnson spot, neck blast, wheat blast and Imochi (稲熱), is a plant-pathogenic fungus and model organism that causes a serious disease affecting rice. It is now known that M. grisea consists of a cryptic species complex containing at least two biological species that have clear genetic differences and do not interbreed. Complex members isolated from Digitaria have been more narrowly defined as M. grisea. The remaining members of the complex isolated from rice and a variety of other hosts have been renamed Magnaporthe oryzae, within the same M. grisea complex. Confusion on which of these two names to use for the rice blast pathogen remains, as both are now used by different authors.
Uncinula necator is a fungus that causes powdery mildew of grape. It is a common pathogen of Vitis species, including the wine grape, Vitis vinifera. The fungus is believed to have originated in North America. European varieties of Vitis vinifera are more or less susceptible to this fungus. Uncinula necator infects all green tissue on the grapevine, including leaves and young berries. It can cause crop loss and poor wine quality if untreated. The sexual stage of this pathogen requires free moisture to release ascospores from its cleistothecia in the spring. However, free moisture is not needed for secondary spread via conidia; high atmospheric humidity is sufficient. Its anamorph is called Oidium tuckeri.
Jonathan Dallas George Jones is a senior scientist at the Sainsbury Laboratory and a professor at the University of East Anglia using molecular and genetic approaches to study disease resistance in plants.
Blumeria graminis is a fungus that causes powdery mildew on grasses, including cereals. It is the only species in the genus Blumeria. It has also been called Erysiphe graminis and Oidium monilioides or Oidium tritici.
The gene-for-gene relationship is a concept in plant pathology that plants and their diseases each have single genes that interact with each other during an infection. It was proposed by Harold Henry Flor who was working with rust (Melampsora lini) of flax (Linum usitatissimum). Flor showed that the inheritance of both resistance in the host and parasite ability to cause disease is controlled by pairs of matching genes. One is a plant gene called the resistance (R) gene. The other is a parasite gene called the avirulence (Avr) gene. Plants producing a specific R gene product are resistant towards a pathogen that produces the corresponding Avr gene product. Gene-for-gene relationships are a widespread and very important aspect of plant disease resistance. Another example can be seen with Lactuca serriola versus Bremia lactucae.
Leptosphaeria maculans is a fungal pathogen of the phylum Ascomycota that is the causal agent of blackleg disease on Brassica crops. Its genome has been sequenced, and L. maculans is a well-studied model phytopathogenic fungus. Symptoms of blackleg generally include basal stem cankers, small grey lesions on leaves, and root rot. The major yield loss is due to stem canker. The fungus is dispersed by the wind as ascospores or rain splash in the case of the conidia. L. maculans grows best in wet conditions and a temperature range of 5–20 degrees Celsius. Rotation of crops, removal of stubble, application of fungicide, and crop resistance are all used to manage blackleg. The fungus is an important pathogen of Brassica napus (canola) crops.
Powdery scab is a disease of potato tubers. It is caused by the cercozoan Spongospora subterranea f. sp. subterranea and is widespread in potato growing countries. Symptoms of powdery scab include small lesions in the early stages of the disease, progressing to raised pustules containing a powdery mass. These can eventually rupture within the tuber periderm. The powdery pustules contain resting spores that release anisokont zoospores to infect the root hairs of potatoes or tomatoes. Powdery scab is a cosmetic defect on tubers, which can result in the rejection of these potatoes. Potatoes which have been infected can be peeled to remove the infected skin and the remaining inside of the potato can be cooked and eaten.
Microsphaera diffusa is a plant pathogen. M. diffusa infections on soybeans are referred to as powdery mildew.
Barley, a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains; it was domesticated in the Fertile Crescent around 9000 BC, giving it nonshattering spikelets and making it much easier to harvest. Its use then spread throughout Eurasia by 2000 BC. Barley prefers relatively low temperatures to grow, and well-drained soil. It is relatively tolerant of drought and soil salinity, but is less winter-hardy than wheat or rye.
Thinopyrum intermedium, known commonly as intermediate wheatgrass, is a sod-forming perennial grass in the Triticeae tribe of Pooideae native to Europe and Western Asia. It is part of a group of plants commonly called wheatgrasses because of the similarity of their seed heads or ears to common wheat. However, wheatgrasses generally are perennial, while wheat is an annual. It has gained the Royal Horticultural Society's Award of Garden Merit as an ornamental.
Plant disease resistance protects plants from pathogens in two ways: by pre-formed structures and chemicals, and by infection-induced responses of the immune system. Relative to a susceptible plant, disease resistance is the reduction of pathogen growth on or in the plant, while the term disease tolerance describes plants that exhibit little disease damage despite substantial pathogen levels. Disease outcome is determined by the three-way interaction of the pathogen, the plant and the environmental conditions.
Triticum carthlicum Nevski, 1934, the Persian wheat, is a wheat with a tetraploid genome.
Leymus mollis is a species of grass known by the common names American dune grass, American dune wild-rye, sea lyme-grass, strand-wheat, and strand grass. Its Japanese name is hamaninniku. It is native to Asia, where it occurs in Japan, China, Korea, and Russia, and northern parts of North America, where it occurs across Canada and the northern United States, as well as Greenland. It can also be found in Iceland.
Catherine Feuillet is a French geneticist who is currently the Chief Scientific Officer of Inari Agriculture, a Cambridge MA based biotechnology company. Feuillet earned a PhD in plant molecular biology on the isolation and characterization of genes involved in wood formation in eucalyptus trees. She started to work on the genetics of disease resistance in wheat in 1994 during her post-doctoral studies at the Swiss Federal Institute for Agroecology. She then moved as a junior group leader to the University of Zurich where she investigated the molecular basis of fungal disease resistance in wheat and in barley and cloned the first leaf rust resistance gene from wheat. In 2004 she was hired as a research director at the Institut National de la Recherche Agronomique (INRA) in France to lead European and international projects on wheat genomics.
Ernest Robert Sears was an American geneticist, botanist, pioneer of plant genetics, and leading expert on wheat cytogenetics. Sears and Sir Ralph Riley (1924–1999) are perhaps the two most important founders of chromosome engineering in plant breeding.
Mildew locus o (MLO) is a plant-specific gene family. Specific members of the Mildew Locus O gene family act as powdery mildew susceptibility factors. Their inactivation, as the result of a loss-of-function mutation, gene knock-out, or knock-down, is associated with a peculiar form of resistance, referred to as mlo resistance. The mlo gene family is widely conserved across the plant kingdom with some members evolving as early as the first land plants. Mlo proteins contain seven highly conserved transmembrane domains, as well as a calmodulin-binding domain. TaMLO genes are the MLOs in bread wheat, Triticum aestivum.
2Blades is an agricultural phytopathology non-profit which performs research to improve durable genetic resistance in crops, and funds other researchers to do the same. 2Blades was co-founded by Dr. Roger Freedman and Dr. Diana Horvath in 2004.