HMB435H1 Lecture Notes - Covalent Bond, Actin, Integrin
Document Summary
Migration: requires a machinery to convert chemical energy to kinetic energy two types of migrations: mesenchymal and ameboid. two types of ameboid migrations: one that needs actin to occur and one doesn"t (blebbing) Ameboid migration doesn"t need a stable surface. Eg neutrophils move in ameboid fashion in blood. Mesenchymal migration requires integrins: connect the outside with the inside to provide connection with a stable surface for movement. Blebbing; a new idea, not fully formed or accepted: does not need. Actin. cell body attaches weakly to the surface and the cytoskeleton breaks to form a bubble, the insides fill/spill into the new bubble" eg. tumour cells do this. Tumour cells can be both ameboid and mesenchymal. Experiment: actin"s function in migration was determined by inhibiting actin polymerization when this was done, migration stopped. Actin is a slow enzyme: the barbed end (+) has a low kd and is more energetically favourable side to add the monomers to add onto.
