Chromosomes carry genetic information in the form of DNA, also called the code of life. Mutations in this code can lead to genetic diseases and disorders.
Researchers have been curious to know how this genetic information is organised and packaged into chromosomes. How is DNA packaged in normal conditions, and how it changes in different disease states. The composition and the number of chromosomes are altered in many diseases. How do these changes occur, and what is their impact on a disease?
One possible means for researchers to visualise what exists inside chromosomes is through microscopy. Chromosomes were first observed under the microscope in the 19th Century. Since then, imaging technology advances have helped us know their size, shape, number, and placement inside the cell's nucleus. It has also helped researchers identify numerical and structural changes in chromosomes that occur in diseases such as cancer.
Since Jansen invented the single-lens optical microscope in 1595, this technology has evolved and achieved many milestones. The 21st-century microscopes now allow fluorescence assessment of chromosomes using advanced modalities such as fluorescence lifetime imaging (FLIM) and super-resolution microscopy (SRM).
A review article by AKU-CRM's Dr Mohammed Yusuf and his team, in collaboration with Professors Stanley Botchway and Ian Robinson, highlights that both FLIM and SRM can provide nanoscale information of chromosomes and their structure. SRM or "nanoscopy" can generate images of DNA with less than 50-nanometer resolution, while FLIM, when coupled with energy transfer, could provide less than 20-nanometer information.
The authors shed light on the advantages of using these two microscopes for providing nanoscale information about chromosome structure and compaction. Furthermore, they summarise the research studies done to date using these technologies. The authors discuss the limitations and highlight the prospects of how advancements in these technologies can contribute to chromosome science. They hope that such imaging methods, together with different labelling strategies and integration with other modalities, will reveal the unsolved chromosome mysteries and support a more in-depth understanding of chromosomes.
Read the full article https://pubmed.ncbi.nlm.nih.gov/33686484/
About the authors
Mohammed Yusuf, Assistant Professor, Centre for Regenerative Medicine and Stem Cell Research, Aga Khan University and London Centre for Nanotechnology, University College London, London, UK
Atiqa Sajid and Safana Farooq, Research Associates, Centre for Regenerative Medicine and Stem Cell Research, Aga Khan University
Stanley Botchway (Professor in Biophysics), Central Laser Facility, Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory, Research Complex at Harwell, Oxford, UK
Ian K Robinson (Professor of Physics), London Centre for Nanotechnology, University College London, London, UK