Study Reveals Cell Reactions under Extracellular Physical Stimuli
Prof. Dong Hwee Kim publishes paper in Nature Communications

▲ Professor Dong Hwee Kim, KU-KIST Graduate School of Converging Science and Technology

Professor Dong Hwee Kim of the KU-KIST Graduate School of Converging Science and Technology revealed a mechanism of cellular responses to extracellular physical stimuli by observing the deformation of a nucleus.

The results were published in Nature Communications, a world-renowned journal in the field.
(*Title of Article: Nuclear lamin A/C harnesses the perinuclear apical actin cables to protect nuclear morphology)

The Applied Mechanobiology Group, led by Professor Kim, developed a stretching device to simulate physical stimuli such as the pulse of a heart, flow of body fluids, and stretching of skin. Physical stimuli were applied to cells containing green fluorescent protein (GFP) and lamin A/C*, and cellular changes were monitored in real-time using a confocal laser scanning microscope (CLSM)* and 3D image reconstruction. The study revealed the mechanism behind gradual deformation of the cytoskeleton* and 3D structure of the nucleus under physical stimuli, and demonstrated that the loss of lamin A/C in the nuclear envelope causes greater damage to the nucleus.
* Nucleus: Contains the majority of the cell’s genetic material. Important functions such as DNA replication and transcriptional control occur within the nucleus. Morphological changes of the nucleus are associated not only with physiological activities, but also degenerative genetic diseases such as cancer, muscular dystrophy, and progeria.
* Green fluorescent protein: A fluorescent protein that emits bright green fluorescence when activated by calcium ions or energy is received from a specific protein. Widely used as a marker for gene expression in biological research.
* Lamin A/C: A protein that constitutes the nuclear membrane. Provides physical protection for the nucleus, and is associated with various diseases.
* Confocal laser scanning microscope (CLSM): Unlike general fluorescent microscopy, CLSM provides high-resolution, 3D reconstructed images by scanning samples sequentially point by point.

The team developed and experimentally verified their previous mathematical model on changes of the nucleus under intracellular forces. The results not only shed new light on the dynamics of organelles in relation to disease onset and progression, but also contribute to the establishment of new therapeutic strategies. 

Professor Kim said, “This paradigm shift of adopting a physics-based approach to understand biological phenomena is expected to pave the way for multidisciplinary solutions to longstanding issues in biology.”