BIOB10H3 Lecture Notes - Lecture 10: Nuclear Membrane, Colchicine, Jerky
4 Oct 2016
School
Department
Course
Professor
Document Summary
Cytosol fluid matrix surrounding organelles contains water, ions, sugars, atp. What is the targeting sequence for proteins destined to stay in cytosol? targeting sequence = no targeting sequence proteins are translated in cytosol and stay there by default . Chaperone proteins, soluble receptors for transport of organelle proteins. 3 components: microtubules, actin, intermediate filaments extensive protein networks. Made on free ribosomes with no targeting sequence. Microtubules (mts) composed of tubulin heterodimers each with a- and b-tubulin subunits polymerize to make mts tertiary structure from x-ray crystallography tubulin heterodimers - b-tubulin binds gtp to allow polymerization. Gtp slowly converted to gdp after incorporation into mt wall polymerize into a protofilament. With a plus (+) and minus (-) end ends are structurally a little different (-) ends embedded in the centrosome. Mt-organizing centre (mtoc) - where polymerization begins. Expt start with y-tubulin slightly different structure than a and b tubulin (+) ends extend towards the plasma membrane.
