An award is made to the University of California Santa Cruz to add long-wavelength excitation light (1,550 nm) and adaptive optics (AO) into a commercial multiphoton microscope (Olympus) for live deeptissue biological imaging. Adaptive optics has provided diffraction-limited images for large ground-based telescopes by correcting for the blurring caused by the atmosphere. They propose to re-apply similar adaptive optics techniques in multiphoton microscopy to obtain diffraction-limited images from deep within living biological tissues. This development will provide biologists with new imaging capabilities, similar to advantages adaptive optics provided to astronomers, enabling them to obtain the highestresolution deep-tissue images in neurobiology to study brain development and synapse plasticity in the nervous system, in cell biology to study cell cycle events, and in developmental biology to study stem cells, chromatin remodeling and the cytoskeleton. The research activities in this project include opportunities for undergraduate and graduate students to participate in a multidisciplinary research team consisting of optical physicists, electrical engineers, and biologists, contributing to their training as the next generation of instrumentalists and advanced users. The research activities and instrumentation will be integrated into teaching at the undergraduate and graduate levels through hands-on projects in engineering and science courses at UCSC, a Hispanic Serving Institution (HSI), and through an NSF sponsored outreach program, the California State Summer School for Mathematics and Science(COSMOS), a summer residential program for high school scholars with demonstrated interest and achievement in math and science. They will also work in a partnership with all ten UC campuses and three affiliated national labs (LANL, LBNL, and LLNL) and industry to broadly disseminate the technology to the biological research community. Such improvements will benefit society by greatly advancing our fundamental understanding of life processes at the cellular and sub-cellular levels.
The proposed activity more than doubles the depth (>1,500nm) of diffraction limited imaging (738 nm) into dynamic live tissue (AO frame rate >1 Hz) where many fundamental cellular processes occur, such as neuron growth, organization and synapse formation. For example, by increasing the imaging depth from 500 um to 1,000 um, they can reach the deeper cortical layers to see if synaptic reorganization during development and under pathological conditions follows similar rules as in the superficial cortical layers, were synapses are constantly remodeling in living animals. By increasing the imaging depth beyond 1,000 um they can reach the Hippocampus, the site for learning and memory. This will allow studies of how synapses reorganize during learning and how they encode for long-lasting memory.