BIOL 205 Chapter Notes - Chapter 7: Nuclear Pore, Nucleoplasm, Cytosol
Document Summary
Wwu bio 205: many identical rna copies can be made from the same gene and each rna molecule can direct the synthesis of many identical protein molecules. Whereas dna functions solely as an information store, some rnas have structural, regulatory or catalytic roles: in eukaryotes, the total number of pre mrna transcripts that are synthesized -only a small fraction- will be useful to the cell. The remaining rna fragments are not only useless but can be dangerous to the cell. How does the cell distinguish between relatively rare mature mrna molecules it needs to export to the cytosol and the overwhelming amount of debris generated by. Answer: transport of mrna from nucleus to cytosol (where mrna is translated into protein) is highly selective. Selective transport mediated by nuclear pore complexes, which connect the nucleoplasm with the cytosol and act as gates that control which macromolecules can enter or leave the nucleus.
