Plant Reproductive Biology
Head: Dr. Jochen Kumlehn
The scientific interest of the research group Plant Reproductive Biology is focussed on plant developmental processes which are related to the recombination of genetic information. Processes such as gametophyte development, fertilization as well as embryogenesis and seed development constitute the main subjects of investigation and manipulation.
The group has special expertise in developing and employing contemporary cell culture systems and genetic transformation technology for cereals and grain legumes which are considered recalcitrant concerning gene transfer. In numerous projects we are aiming to functionally characterise newly identified promoters and genes by ectopic expression or knock-down experiments. By genetic transformation approaches we also want to contribute to crop improvement and molecular farming. Currently running projects focus on resistance against pathogenic viruses and fungi as well as on the employment of crops to produce recombinant vaccines and antibodies.
To establish an experimental platform for the study of zygotic, somatic and pollen embryogenesis, methods have been developed to isolate, culture and manipulate egg cells, zygotes, young embryos and immature pollen. By live-cell monitoring as well as by the use of highly specific cDNA libraries from selected single cells we are approaching a cell-biological and molecular characterisation of early embryogenesis and apomixis-related processes. The group is further engaged in the development and employment of doubled haploid technology to be used for plant breeding and genetic transformation.
The PARASIT project
Pathogen resistance achieved by plant-induced silencing
of fungicide target genes
Dr. Jochen Kumlehn (principal investigator), Krishna Mohan Pathi (PhD student)
Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben,
Plant Reproductive Biology
Prof. Dr. Holger B. Deising (principal investigator), Maximilian Groß (PhD student)
Martin Luther University Halle-Wittenberg, Inst. for Agricultural and Nutritional Sciences, Phytopathology and Plant Protection
Project duration: 01.12.2016 – 30.11.2019, Funding amount: 247.000 €
Protection of plants against pathogenic fungi is indispensable for a sustainable and safe agricultural production. Chemical plant protection and the establishment of plant resistance via classical plant breeding have the major limitation that the genetic adaptation of fungi to cope with plant resistance (R) genes and fungicides typically takes few years only.
The PARASIT project takes advantage of host-induced gene silencing (HIGS) which has first been demonstrated in plants by IPK researchers (Nowara et al. 2010, The Plant Cell 22, 3130-3141). HIGS involves the plant to express inverted repeat or anti-sense transcripts with homology to fungus-specific target genes. In the context of infection, these transcripts are taken up by invading fungi which effects the down-regulation of their target gene(s) via a mechanism conserved across most eukaryotic organisms coined RNA interference (RNAi). If HIGS is targeted against essential fungal genes, it can lead to declining virulence. HIGS approaches feature several unique advantages such as exceedingly high specificity, durability and avoidance of side-effects due to the expendability of any modified proteinaceous or metabolic component.
Within the scope of the PARASIT project, β-tubulin (TUB2) as well as succinate dehydrogenase (SDH1 to 4) genes of the maize anthracnose-causing pathogen Colletotrichum graminicola have been chosen as HIGS targets. The proteins encoded by these genes serve as targets for two important fungicide classes. Inhibition of TUB2 disturbs cell division, whereas inhibition of SDH affects fungal respiration by perturbing the mitochondrial electron transport chain. The expected outcome of the PARASIT project is that plant-mediated down-regulation of the chosen target genes will be durably effective, irrespective of whether the fungal pathogen may develop resistance against the corresponding fungicides.