Reduction of Human and Animal Disease through Genomics and Genetics
The conversion of light to chemical energy during photosynthesis is one of the most important biochemical pathways on the planet. In a world of climate change and limited fossil energy resources, alternative and sustainable technologies to harvest and store light energy are highly desirable. Artificial photosynthetic systems could significantly contribute to clean energy production. However, to design such devices, a detailed understanding of all components involved in natural photosynthesis is needed. A very detailed knowledge about the direct protein components of the photosynthetic machinery has been acquired over the last decades, but little is known about the importance of indirect components like the chloroplast ion homeostasis for photosynthesis. We have shown recently that a disturbance of the plastidial ion homeostasis has dramatic consequences on photosynthetic efficiency in the model plant Arabidopsis thaliana.
Biomembranes that define the boundaries of cells and their organelles are impermeable for ions. Therefore, specific transport proteins facilitate ion exchange across membranes to maintain ion homeostasis in the organelles according to the physiological status of the plant cell. The ion homeostasis is sensitive towards abiotic stress, mostly in the form of salt stress. Excessive irrigation related to climate change and drought, has led to soil salinity becoming a growing global issue. Salt stress caused by NaCl accumulation in plant cells damages the chloroplast, leads to chlorophyll loss and poor photosynthesis rates.
The long-term goal of the research in the Kunz lab is a systemic understanding of the chloroplast ion homeostasis, the dynamics and how this feeds into photosynthesis and energy storage. Moreover, we are exploring how the chloroplast fights abiotic stress and which transporter genes and other genetic components are involved in this process. Identified genes from this research will be tested for their potential to increase photosynthetic efficiency under unfavorable environmental conditions.
In our research we employ different plant species, such as the dicot model organism Arabidopsis thaliana and Oryza sativa as a monocot and crop plant. We apply a variety of latest molecular biology tools and specific photosynthesis tools to design or study our plant mutants of interest. Our lab provides a challenging and team-work oriented training environment for undergraduates and graduate students with experienced researchers on staff.
Please feel free to contact me if you are interested in our research, collaborations or would like to join our scientific team.
Selected Publications 2009-2014
Kunz HH, Gierth M, Herdean A, Satoh-Cruz M, Kramer DM, Spetea C, Schroeder JI. Plastidial transporters KEA1, -2, and -3 are essential for chloroplast osmoregulation, integrity, and pH regulation in Arabidopsis. Proc Natl Acad Sci U S A. Vol. May 20;111(20):7480-5. 2014
Müller M, Kunz HH, Schroeder JI, Kemp G, Young HS, Neuhaus HE. Decreased capacity for sodium export out of Arabidopsis chloroplasts impairs salt tolerance, photosynthesis and plant performance. Plant J. Vol. May;78(4):646-58. 2014 Other Significant Publications
Kunz HH, Zamani-Nour S, Häusler RE, Ludewig K, Schroeder JI, Malinova I, Fettke J, Flugge UI, Gierth M. Loss of Cytosolic Phosphoglucose Isomerase (cPGI) affects carbohydrate metabolism in leaves and is essential for fertility of Arabidopsis thaliana. Plant Physiol. Vol. Oct;166(2):753-65. 2014
Kim TH, Kunz HH, Bhattacharjee S, Hauser F, Park J, Engineer C, Liu A, Ha T, Parker JE, Gassmann W, Schroeder JI. Natural variation in small molecule-induced TIR-NB-LRR signaling induces root growth arrest via EDS1- and PAD4-complexed R protein VICTR in Arabidopsis. Plant Cell Vol. Dec;24(12):5177-92. 2012
von Berlepsch S, Kunz HH, Brodesser S, Fink P, Marin K, Flügge UI, Gierth M. The Acyl-Acyl Carrier Protein Synthetase from Synechocystis sp. PCC6803 mediates Fatty Acid Import. Plant Physiol. Vol. Jun;159(2):606-17. 2012
Kunz HH, Scharnewski M, von Berlepsch S, Shahi S, Fulda M, Flügge UI, Gierth M. Nocturnal energy demand in plants: insights from studying mutants impaired in β-oxidation. Plant Signal Behav. Vol. Jul;5(7):842-4. 2010
Kunz HH, Scharnewski M, Feussner K, Feussner I, Flügge UI, Fulda M, Gierth M. The ABC transporter PXA1 and peroxisomal beta-oxidation are vital for metabolism in mature leaves of Arabidopsis during extended darkness. Plant Cell Vol. Sep;21(9):2733-49. 2009