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Measuring Nanoscale Chromatin Heterogeneity with Partial Wave Spectroscopic Microscopy
Scott Gladstein1, Andrew Stawarz1, Luay M Almassalha1
1Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA.
Methods in Molecular Biology (Clifton, N.J.)
|February 25, 2018
Summary
Understanding higher-order chromatin topology is limited. Partial wave spectroscopic (PWS) microscopy now allows real-time imaging of chromatin nanoenvironment in live cells, revealing its functional roles.
Area of Science:
- Cell Biology
- Biophysics
- Microscopy
Background:
- Higher-order chromatin topology (20-200 nm) is crucial for biological processes but poorly understood due to imaging limitations.
- The cellular nanoenvironment, defined by chromatin organization, critically influences chemical reactions and cellular functions.
- Dysregulation of chromatin topology is implicated in cancer development.
Purpose of the Study:
- To explain the importance of studying chromatin topology.
- To describe the theory, instrumentation, and application of partial wave spectroscopic (PWS) microscopy.
- To provide a guide for PWS measurements, analysis, and troubleshooting.
Main Methods:
- Utilizing partial wave spectroscopic (PWS) microscopy for label-free, real-time measurement of chromatin organization.
- Quantifying nanoscale mass density variations (heterogeneity) within live cells using PWS.
- Detailed explanation of PWS measurement and analysis processes.
Main Results:
- PWS microscopy overcomes previous limitations in imaging higher-order chromatin topology.
- Real-time PWS measurements reveal the dynamic nanoenvironment within live cells.
- PWS enables the study of chromatin's role in gene regulation and cancer.
Conclusions:
- Advancements in PWS microscopy provide unprecedented insights into chromatin nanoenvironment.
- Understanding chromatin topology is key to deciphering fundamental biological processes.
- PWS is a powerful tool for investigating cellular functions and disease mechanisms.
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