MCB 150 Lecture Notes - Lecture 25: Leucine, Guanine Nucleotide Exchange Factor, Nuclear Pore
Document Summary
Traffic through the nuclear pore complex depends on size. <20 kda pass freely through passive diffusion. Will require energy in the form of gtp hydrolysis produced in the cytoplasm. Not really going to be asked about this. Why keep them out of the nuc. Things with the right signal will be brought in. Discovered by dan kalderon and alan smith ided a nuclear localizing. Signal (nls) in viral protein known to enter the nuc. This is required to enter the nuc . removal of sequence will not be allowed in if missing the nls. Recognized by the nuclear pore complex (npc) One type of npc per multiple types of nls. Importin is a molecule that recognizes a nls. Binds to nls via protein protein interactions. Its allowed into the cell (think of enzyme facilitated endocytosis) Ran-gtp (made from gdp gtp) has a nucleotide binding site (for gtp or gdp) and is used to break off importin from the cargo protein.