BIOL 201 Lecture Notes - Lecture 18: Endosome, Syntaxin, Secretion
26 Jan 2016
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Document Summary
Substances enter and leave nuclei through nuclear pore complexes. Outer and inner nuclear membrane faces cytoplasm and nucleoplasm. Associated with the 7 complex are fg proteins. > 40 kda proteins require nuclear localizaton signal (nls) to enter. Cargo protein binds nuclear import receptor (importin) via nls. Complex enters nucleus via pore importin associates with nucleoporins. Fg proteins guide importin - cargo complex through pore. Ran gdp has low affinity for importin, complex dissociates. Coat proteins determine which proteins incorporated as cargo. Integral membrane proteins included into vesicle include v-snares. Protein coat disassembles after vesicle budding - exposes v-snares. V-snares bind specifically to t-snares on target membrane vesicle fusion. Vesicle formation initiated by association of gtp-binding protein with parent membrane. Gtp exchange for gdp anchors protein in membrane. Gtp binding protein associates with coat component. Coat subunits associate with integral membrane cargo protein. Some membrane cargo proteins receptors for soluble cargo proteins. Rab proteins: gtp binding proteins with lipid anchor.
