Profiling Chromosome Topological Features by Super-Resolution 3D Structured Illumination Microscopy

Area of Science:

• Genomics
• Cell Biology
• Microscopy

Background:

• Nuclear architecture and genome topology are crucial for cellular function.
• Three-dimensional structured illumination microscopy (3D-SIM) and 3D fluorescence in situ hybridization (3D-FISH) enable super-resolution visualization of nuclear structures.
• Chromosome Territories (CTs) represent the spatial organization of individual chromosomes within the interphase nucleus.

Purpose of the Study:

• To detail a workflow for applying 3D-SIM to 3D-FISH preparations for analyzing chromosome territories.
• To provide guidelines for sample preparation, image acquisition, and quantitative image analysis of CTs.
• To investigate the topological features of CTs 9 and 22 in the context of the t(9;22) translocation in Chronic Myeloid Leukemia (CML).

Main Methods:

• Application of 3D-SIM for super-resolution imaging of 3D-FISH stained chromosomes.
• Development of a comprehensive protocol for sample preparation and image acquisition.
• Quantitative image analysis for profiling topological features of Chromosome Territories.

Main Results:

• Successful visualization and quantitative profiling of Chromosome Territories (CTs) using 3D-SIM and 3D-FISH.
• Characterization of large-scale topological disruption in CTs 9 and 22 in CML patients with the t(9;22) translocation.
• Correlation between CT topological disruption and patient response to cancer treatment.

Conclusions:

• 3D-SIM combined with 3D-FISH is a powerful method for analyzing nuclear architecture and genome topology.
• CT topological features are altered in CML and may correlate with treatment outcomes.
• Microscopy-based analysis of genome topology offers new insights into cancer biology and treatment response.