Chromosome Tethering to the Lamina Increases Chromosome Compartmentalization

Proteins on the nuclear lamina often tether pieces of heterochromatin thus limiting their movement. We simulated the interaction between heterochromatin and the nuclear lamina for three different interaction strengths by modeling chromatin as a block copolymer inside the nucleus with certain monomers set to interact with an implemented wall. We go on to show that our model was capable of successfully attracting heterochromatin and giving it a sticking propensity to the nuclear lamina. We found that stronger lamina-chromosome interaction led to an increase in the overall number of compartments which may uncover a possible role of the nuclear lamina in regulating gene expression. We believe our model represents a significant upgrade to the Minimal Chromatin Model by Di Pierro, et al., and believe its highly customizable base model will allow further research into different kinds of lamina-chromosome interactions. This project was completed with contributions from Sumitabha Brahmachari from Rice University.