Mark M. Metzstein, Ph.D.


Our lab uses genetics and molecular biology in Drosophila to address two basic questions in cell biology: cell morphogenesis and RNA stability.

For cell morphogenesis, we are studying the development of a specific cell type in the insect respiratory system, the tracheal terminal cell. These remarkable cells each form a complex network of subcellular branches in response to oxygen requirements in underlying tissues. To facilitate the flow of gases each of these branches undergoes further morphogenesis, forming air-filled tubes running through each branch. By identifying mutations affecting branching and/or tube formation, we are learning how cells build complex 3-dimensional architectures required for their functions.

For RNA stability, we are studying the cellular surveillance pathway of nonsense mediated mRNA decay (NMD). NMD functions to identify transcripts that contain certain signals, such as premature stop codons, so as to target these RNAs for rapid destruction. In this way NMD functions to regulate expression of both normal and abnormal genes. We are interested in defining the cis-acting signals and trans-acting components required for NMD and in identifying the endogenous targets of this pathway required for normal development and physiology.