Evolution and function of vertebrate globins

• Applicant: Professor Dr. Thorsten Burmester
• Subject Area: Animal Physiology and Biochemistry
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 257057960

Globins are small iron-heme proteins that bind oxygen and thus play an important role in the animal's respiration and oxidative energy production. Hemoglobin and myoglobin are among the best investigated proteins in biomedical sciences, and are a model system to study protein function and evolution. In recent years, our studies led to the identification of six additional globin types in vertebrate (androglobin, neuroglobin, cytoglobin, globin E, globin X and globin Y). The functions of these "novel" globins are still poorly understood and subject of the present application. Analyses of globin relationships, globin gene repertoire and gene order (synteny) allow delineating the evolutionary history of globins. We will specifically focus on the globins of the lamprey, which provide information on the early evolution of vertebrate globins, and of turtles, which possess all eight globin types and thus allow studying their sub-functionalisation. Expression analyses in these species will provide clues about the tissue- and cell-specific roles in both species. Functional analyses will be carried out in stably transfected vertebrate cell lines. The ability of different globins to augment mitochondrial respiration, to mediate tolerance towards hypoxia and reactive oxygen (ROS), to protect lipids, to protect from apoptosis and their roles in the generation of ROS and NO will be tested. This comparative approach will allow evaluating different hypothesis of globin functions and hopefully allow the identification the physiological role of each globin. Kinetic and structural data will be obtained for selected globins. The combination of the results from the phylogenetic and functional experiments will allow us to trace the changes of physiological roles that occurred in the vertebrate globin family during evolution.

• DFG Programme: Research Grants