Cohesin-mediated 3D genome organization plays an essential role in key biological processes including gene transcriptional regulation, DNA replication and repair, cell cycling, receptor diversity on cell surface (such as B-, T- and nerve cells) and memory. Cohesin-based loop extrusion is started from a loading site and then extend in two sides, leading to a symmetrical DNA-DNA contact pattern. Cohesin sliding on chromatin is anchored at a pair of convergent sites binding transcription factor CTCF, indicating that the information encoding specific chromatin contacts including enhancer-promoter communications involved in gene regulation can be stored in the genome. On the other hand, the arrangement of CTCF sites can block unwanted chromatin contacts to function as a transcriptional insulator. Thus, the specificity of Cohesin-based chromatin organization can be defined by, 1) the position of Cohesin uploading site and loading frequency; 2) the position of Cohesin-driven loop extrusion barrier, such as CTCF-binding sites.

Speaker

 A/Prof. Ya Guo

School of Life Science and Technology, SJTU

Time

        2023.3.15 12:00-13:30