October 22:WOMEN OF GAIRDNER

Dr. Iva Greenwald received her B.S. from Cornell in 1977, her Ph.D. from MIT in 1982, and conducted postdoctoral research at the MRC Laboratory of Molecular Biology from 1983-1986.  She then joined the faculty of Princeton University (1986-1993) and moved to the Dept. of Biochemistry and Molecular Biophysics on the medical campus of Columbia University in 1993. Since 2016, Dr. Greenwald has had a primary appointment in the Dept. of Biological Sciences on the Morningside campus of Columbia. Her honors include election to the National Academy of Sciences (USA) in 2005.

Dr. Greenwald's work on the conserved LIN-12/Notch signaling system falls into two partially overlapping phases. In the first phase, she identified and elucidated the fundamental properties of the system, including (i) its role as a binary switch for regulating alternative cell fate decisions, (ii) its sequence as a transmembrane protein and its function in signal-reception, (iii) its archetypal role and mode of action in the feedback amplification of intercellular signals, (iv) the discovery of the intramembrane protease Presenilin as a core component of the Notch signaling system, and characterization of other core components, and (v) together with Dr. Gary Struhl, the novel “cleavage and nuclear import” mechanism of signal transduction and for Presenilin in executing the transmembrane cleavage event. In the second phase, she focused on identifying (i) new regulators of LIN-12/Notch activity, trafficking and stability, such as the tumor suppressor SEL-10/FBXW7, (ii) target genes and genetic circuitry, and (iii) how LIN-12/Notch and other signals are integrated during development.