High-spatial and colourimetric imaging of histone modifications in single senescent cells using plasmonic nanoprobes

Abstract

Histones are closely related to the state of chromatin, and epigenetic modification of their tail results in regulation in cells. Therefore, developing various analytical tools to map the changes in position and distribution of histone modifications is helpful in studying underlying mechanisms. Herein, we propose a high-spatial and colourimetric imaging method using plasmonic nanoparticles as probes to visualize heterochromatin histone markers in a single nucleus. We visualized the reorganization between repressive histone markers, H3K9me3 and H3K27me3, caused by oncogene-induced senescence based on the scattering colours and spectral shift of plasmonic nanoprobes to longer wavelengths using their distance-dependent coupling effect. The measured scattering profiles were correlated with the computation results simulating the scattering spectra according to the arrangements and distances among the plasmonic nanoprobes. The plasmonic nanoprobe-based high-spatial hyperspectral imaging provides an advanced way to study the dynamics of histone modifications for predicting the progression of diseases or senescence.

Multiple Stepwise Synthetic Pathways toward Complex Plasmonic 2D and 3D Nanoframes for Generation of Electromagnetic Hot Zones in a Single Entity

“…Specifically, because the strong local electric fields (i.e., hot spots) are enhanced on sharp tips due to the lightning rod effect (panel i in Figure a) and become significantly boosted when narrow gaps are formed among adjacent metallic NPs through interparticle plasmonic coupling, a wide range of plasmonic gap-based applications have been investigated, from chemical and biological sensing, imaging, and therapeutics to plasmon-enhanced energy production. , Although attempts have been made to use plasmonic dimers, random aggregates, or nanoparticles on film with a dielectric spacer to produce the plasmonic nanogaps (panel ii in Figure a), precise control of the hot spot is challenging. For example, random aggregates possess multiple interparticle hot spots but the number and positions are uncontrollable with limited active hot spot area per volume of particles.…”