CAREER: Imaging the Chemical Nature of Intracellular Phase Separation by Functional Stimulated Raman Scattering Spectro-microscopy

California Institute Of Technology, Pasadena CA

Investigators

Abstract

With support from the Chemical Measurement and Imaging (CMI) Program, and co-funding from the Chemistry of Life Processes (CLP) Program and the Chemical Structure, Dynamics, and Mechanisms-B (CSDM-B) Program in the CHE Division and the Molecular Biophysics Cluster in the MCB Division, Lu Wei and her research team at the California Institute of Technology are developing new optical imaging strategies that aim to improve our ability to study intracellular phenomena such as those relevant to neurodegenerative diseases. The research will result in new instrumentation, new imaging probes, and new labeling methods, all targeting new chemical insights into the behavior of proteins and RNA in live-cell settings. The highly interdisciplinary program will provide research opportunities for graduate and undergraduate students. Outreach efforts in the Wei group are planned to provide exposure to science to both K-12 and undergraduate students. The formation of liquid-liquid phase separation (LLPS) and its role in biological function has been extensively studied with many exciting new observations and discoveries. However, there is much yet to be learned especially regarding the biophysical and biochemical principles underlying the fundamental interactions among biomacromolecules, particularly protein and RNA and their ability to form condensates. To investigate key intracellular phase-separated condensates in live cells, the Wei lab is developing new stimulated Raman spectral-imaging strategies that are noninvasive and quantitative, and offer high spatial and temporal resolution. Specifically, the research program aims to (1) develop functional vibrational probes and labeling approaches to quantify the composition and sense the intra-condensate interactions from the identified LLPS systems for both in vitro and live-cell interrogations; (2) build new instrumentation modules to achieve up to 20-fold sensitivity enhancement for chemical mapping in live cells; and (3) perform in-depth live-cell investigations with advanced data analysis to piece together unknown chemical features and interaction principles in native and complex cellular settings. This award is co-funded by the CMI, CLP and CSDM-B Programs in the Division of Chemistry in the Directorate for Mathematical and Physical Sciences (MPS) and by the Molecular Biophysics Program in the Division of Molecular and Cellular Biosciences (MCB) in the Directorate for Biological Sciences (BIO). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.