Research-Label-Free SRS Microscopy

We applied label-free SRS microscopy to visualize the content, distribution, composition and dynamics of lipid storage of a transparent model organism, C. elegans. When combined with powerful C.elegans molecular genetics, we hope to understand the genetic regulation of lipid metabolism and, more generally, how energy homeostasis is achieved at the organism's level in the presence of fluctuating environment (Nature Methods 2011). Multidisciplinary study along this line could shed light on the molecular basis of metabolic syndrome such as obesity.


Fig. 1. Visualization of cellular fat storage in lipid droplets using SRS microscopy. (a) Experimental scheme of label-free SRS microscopy for in vivo lipid imaging. PMT, photomultipier tube. (b-d) YFP fluorescence images (b-d), SRS signals e-g) and merged images (h-j) of HEK 293 cells expressing YFP-tagged perilipin A (b,e,h), ADFP (c,f,i) and LSDP5 (d,g,j).

Relevant Papers:
1. A. Folick, W. Min and M. C. Wang. "Label-free imaging of lipid dynamics using Coherent Anti-stokes Raman Scattering (CARS) and Stimulated Raman Scattering (SRS) microscopy", Curr. Opin. Genet. Dev., 21, 1, 2011.[PDF]
2. M. C. Wang*, W. Min*, C. W. Freudiger, G. Ruvkun and X. S. Xie*. "RNAi screening for fat regulatory genes with SRS microscopy", Nature Methods, 8, 135, 2011. *Co-corresponding authors.[PDF]