BIOL 483 Lecture Notes - Lecture 80: Phase Transition, Prc2, Chromatin
Document Summary
Can get different types of condensates that rante from liquid to fibre. In neurogenetrative diseases, chracterised by toxic protein aggregates. Certain proteins that characteristically form aggregates in part o brains that are thought form by aberrant phase transitions. Initially proteins were liquid but matured to solid state. Nucleus allows for primed condition for phase transition. Nucleus is very crowded because f large chromatin polymer that promotes molecular interactions. All nuclear processes that occur on chromatin requires assembly of factors in certain regions - ideally suited to form factory or functional molecular assembly at specific location. If we look closely at chromatin features that favour phase separation, chromatin polymer is intrinsically multivalent (because many repeated sequences) Histone tails have many modifs -> highly disordered, very suitable for weak, multivalent interactions that occur in phase separation. Pcg proteins repress gene expression by modifying chromatin biochemistry and architecture by modifying h3k27me3 and h2a119ub. V important role in large scale chromatin organisation and compaction.
