Which of the following is involved in transpo of large molecules from cytoplasm to the cell nucleus
Transpo of large molecules from cytoplasm to the cell nucleus requires transpo factors like karyopherins called Impoins, Clathrin, Caveolae and Flotillin are all involved in Endocytosis (transpo of molecules from the surface of a cell into the cytoplasm). Impoins are involved in transpo of large molecules from cytoplasm to the cell nucleus. Impoins: Cytoplasm to Nucleus: RAN cycle. Transpo of large molecules from cytoplasm to the cell nucleus requires association with transpo factors like karyopherins called Impoins. The entry and exit of large molecules from the cell nucleus is tightly controlled by the nuclear pore complexes (NPCs) Cargo NLS: Protein that must be impoed to the nucleus from the cytoplasm carry nuclear localization signals (NLS). A NLS is a sequence of aminoacids that acts as a tag. The initial step in translocation through the pore involves binding of Cargo-NLS complex to impoins. The ability of both impoins and expoins to transpo their cargo is regulated by the small Ras related GTPase, RaN. Although no consumption of high-energy phosphatase is needed for translocation through the pore, the energy potential for impo comes from the high nuclear Ran-GTP concentration. Expo is coupled directly to the RamGAP/RanBP1 induced GTP hydrolysis in the cytoplasm. By the addition of cytoplasmic Ran-GTP, the Ran gradient is inveed, nuclear translocation of expo substrates can occur. Such a model is akin to transpo mechanisms of ions through membranes where electrochemical gradients are used to pump ions against their concentration gradient. Clathrin, Caveolae and Flotillin are all involved in Endocytosis (Transpo of Molecules from the surface of a cell into the cytoplasm) (Not from cytoplasm to the Nucleus) Endocytosis involves the capture of material from the surface of a cell and transpo of that material into the cytoplasm. Ref: Guyton and Hall 25th edition
Clathrin
Caveolae
Flotillin
Impoins
General physiology