Parasitic plant/host plant interactions
Parasitic plants live as parasites on and from other plants. This creates huge losses in agriculture when a field of crop plants is infected. Knowledge on the development of these plants is therefore of high importance.
So far, many aspects around parasitic plant/host plant interactions and the chemical warfare that unfolds during attack and defence between them are unknown. We have over the last years developed a set of tools for the parasitic plant genus Cuscuta spp. (dodder) that allow us to approach the molecular mechanisms underlying host plant/parasitic plant interactions. These include a large collection of genomic scaffolds, transcriptomes of four species, proteomic data, sterile callus and shoot cultures, protocols for transient transfections of cells and an extensive microscpic image database including time lapse videos.
- Olsen, S.; Popper, Z.A.; Krause, K. (2016) Two sides of the same coin: xyloglucan endotransglucosylases/ hydrolases in host infection by the parasitic plant Cuscuta. Plant Signalling & Behavior 11
- Olsen, S.; Ketelsen Striberny, B.; Hollmann, J.; Schwacke, R.; Popper, Z.A.; Krause, K. (2016) Getting ready for host invasion: elevated expression and action of xyloglucan endotransglucosylases/hydrolases in developing haustoria of the holoparasitic angiosperm Cuscuta. Journal of Experimental Botany 67, 695-708
- Risan Johnsen, H.; Ketelsen, B.; Olsen, S.; Vidal-Melgosa, S.; Fangel, J.U.; Willats, W.G.T; Rose, J.K.C; Krause, K. (2015) Cell wall composition profiling of parasitic giant dodder (Cuscuta reflexa) and its hosts: a priori differences and induced changes. New Phytologist 207, 805-816
- Ketelsen Striberny, B.; Krause, K (2015). Cell wall glycoproteins at interaction sites between parasitic giant dodder (Cuscuta reflexa) and its host Pelargonium zonale. Plant Signalling & Behavior 10
Cell wall degrading enzymes from parasitic plants
Parasitic plants use hydrolytic enzymes to break down cell walls of their host plants but are able to protect their own cell walls from enzymatic attack.
We study the difference between cell wall composition in the parasite Cuscuta and its hosts and analyze the enzymes involved. This knowledge can help to develop novel, more specific enzyme cocktails for plant biomass hydrolysis. In addition, it helps us understand why some plants are not susceptible to the parasite.
- Risan Johnsen, H.; Krause, K. (2014) Cellulase activity screening using pure carboxymethylcellulose: Application to soluble cellulolytic samples and to plant tissue prints. International Journal of Molecular Sciences 15
Evolution of plastid genomes
Plant cells are divided into "rooms" called compartments or organelles. The compartment that is typical for plant cells are the plastids (or chloroplasts). Plastids possess their own genetic information (the plastid genome or plastome) that contains important information for the biosynthetic pathways located in this compartment.
Most genes on the plastid genome are highly conserved. Different ecological niches can, however, lead to altered evolutionary pressures that, in return, can leave their "footprints" on the plastid genomes. We have examined plastid genomes from the parasitic plant genus Cuscuta and from a thermophilic red alga, Galdieria sulphuraria, with respect to signs of altered evolutionary signatures.
- Krause, K. (2015) Grand-scale theft: Kleptoplasty in parasitic plants?. Trends in Plant Science 20, 1360-1385
- Jain, K.; Krause, K.; Grewe, F.; Nelson, G.F; Weber, A.P.M; Christensen, A.C.; Mower, J.P. (2015) Extreme Features of the Galdieria sulphuraria Organellar Genomes: A Consequence of Polyextremophily?. Genome Biology and Evolution 7, 367-380
- Krause, K.; Scharff, L. (2013) Reduced genomes from parasitic plant plastids: templates for minimal plastomes? Progress in Botany 75, 97 - 115
- Krause K (2011) Piecing together the puzzle of plastome evolution. Planta 234, 647-656
- Tillich M, Krause K (2010) The ins and outs of editing and splicing of plastid RNAs: lessons from parasitic plants. New Biotechnology 27, 256-266
- Vanselow, C., Weber, A.P, Krause, K. and Fromme, P. (2009) Genetic analysis of the photosystem I subunits from the red alga, Galdieria sulphuraria. Biochim Biophys Acta 1787, 46-59
- Krause K (2008) From chloroplasts to "cryptic" plastids: evolution of plastid genomes in parasitic plants. Curr Genet 54, 111-121
- Funk H, Berg S, Krupinska K, Maier U, Krause K (2007) Complete DNA sequences of the plastid genomes of two parasitic flowering plant species, Cuscuta reflexa and Cuscuta gronovii. BMC Plant Biol. 7:45
Integration of plastids into the regulatory network of plant cells
The genetic information in plant cells is distributed between three compartments (nucleus, plastids and mitochondria). To function properly, these genomes are need to communicate with each other to synchronize their expression.
We are investigating how DNA binding proteins that are targeted to the nucleus and to the plastids contribute to the mutual communication between the plant genomes. We focus on thir role in the regulation fo plastid gene expression and their network of interactions in the chloroplast transcriptionally active chomosomes (TAC).
- Fuss, J.; Liegmann, O.; Krause, K.; Rensing, S.A. (2013) Green Targeting Predictor and Ambiguous Targeting Predictor 2: the pitfalls of plant protein targeting prediction and of transient protein expression in heterologous systems. New Phytologist 200, 1022-1033
- Krupinska, K.; Melonek, J.; Krause, K.(2013) New insights into plastid nucleoid structure and functionality. Planta 237, 653-664
- Krause, K. and Krupinska, K. (2009) Nuclear regulators with a second home in organelles. Trends Plant Sci 14, 194-199
- Schwacke R Fischer K, Ketelsen B, Krupinska K, Krause K (2007) Comparative survey of plastid and mitochondrial targeting properties of transcription factors in Arabidopsis and rice. Mol. Genet. Genom. 277, 631-646
- Krause K, Kilbienski I, Mulisch M, Rödiger A, Schäfer A, Krupinska K (2005) DNA-binding proteins of the Whirly family in Arabidopsis thaliana are targeted to the organelles. FEBS Lett. 579, 3707-12
- Legen J, Kemp S, Krause K, Profanter B, Herrmann RG, Maier RM (2002) Comparative analysis of plastid transcription profiles of entire plastid chromosomes from tobacco attributed to wild-type and PEP-deficient transcription machineries. Plant J. 31, 171-188