Welcome to the research projects of Prof. Dr. Julia Kehr
The major aim of my research group is to identify and characterise the molecules moving through the long-distance transport systems, and to determine their exact functions, import and transport mechanisms. A special focus lies on macromolecules like proteins and RNAs that can act as long-distance signals during the responses to abiotic stress and pathogen infection.
To understand the importance of macromolecules for the systemic communication between various plant organs, we apply a combination of physiological, biochemical, molecular and biophysical methods.
Over the last years we could characterize the protein and RNA composition of phloem and xylem sap of various plant species. Furthermore, we have been able to verify that some of the molecules are indeed mobile in living plants and can act as signaling molecules.
Identification and characterisation of macromolecules in the long-distance transport systems
In order to identify macromolecules in the long distance transport systems, we extract samples from xylem and phloem tubes and subject them to mass spectrometry-based proteomics and high-throughput RNA sequencing.
Ongoing research projects include:
- Synthesis, mobility, and functions of specific mobile proteins
- Synthesis, mobility, and functions of small mobile RNAs
- Composition and function of protein-protein and ribonucleoprotein complexes
- Functional-structural characterisation of mobile RNA-binding proteins
- Cell type-specific analysis of mobile proteins and RNAs
Systemic signalling during environmental stress and infection
In order to identify long distance signalling molecules we expose plants to different stress conditions (e.g. drought, pathogens) to find RNAs and proteins that are more abundant in the long distance transport systems under stress and therefore represent candidates for information transmission.
Ongoing research projects include:
- Small RNA signalling under nutrient stress
- The roles of immunophilins during virus infection
- Functions of stress proteins in the phloem
- Functions of tRNA halves under stress conditions
Epigenetic effects of virus infections
EPILOG (epigenetic long-term consequences of viral and bacterial infections) is a joint research project between the University Hospital Eppendorf (UKE), Hamburg University (UHH), and the Heinrich-Pette-Institut for experimental Virology (HPI). The groups involved analyse pathologic and physiologic consequences of epigenetic changes induced by viral and bacterial infections.
The project "Effects of virus infection on local and systemic histone- and DNA modifications " we e´will decipher the epigenetic components of virus infections in plants.
Proteome and protein capabilities in Arabidopsis, Spartina and Populus hybrids
In the new collaborative project "Hybrids – Chances and challenges of new genomic combinations" research groups from the University Hamburg (UHH), the Bernhard-Nocht-institute für Tropenmedizin (BNI) and the Klimaservice Zentrum (GERICS) examine the consequences of hybridisations in nature.
Our project "Hybrid proteome and protein capabilities in Arabidopsis, Spartina and Populus Hybrids" focusses on the consequences of hybridisation on the proteome and on the composition of protein complexes in different plant species. We are using classical proteome studies with 2D-PAGE and mass spectrometry and, in addition, we will apply native analysis of high-molecular-weight protein complexes and a systematic analysis of metabolic pathways (photosynthesis, photorespiration, lipid metabolism) and of stress-dependent enzymes (peroxidases, superoxide dismutases).