Kajimura Mayumi

My research focuses on how various gaseous molecules such as molecular hydrogen (H2), molecular oxygen (O2), NO, H2S, CO2 and CO are sensed in our body. We are particularly interested in the interaction between gaseous molecules and their receptor proteins, gas-sensing proteins and how these gaseous molecules modulate vascular tone in various organs. While the NO signaling has been well-defined, the CO signaling requires further investigation with respect to identifying receptor molecules and their downstream effectors. Like NO, CO has an ability to bind to the ferrous heme of a variety of proteins with high affinity; thus, it is capable of either stimulating or inhibiting catalytic activities of heme proteins. Thus in current studies we are investigating the possibility that CO targets for proteins containing prosthetic heme and by altering their activity it controls the CNS function. We use both in vivo and in vitro systems in parallel to compensate inherent weakness of each model. This requires developing techniques which range from molecular biology, cell biology, protein biochemistry, and single vessel studies to whole animals.