IMM250H1 Lecture 3: week 3 notes.docx
Document Summary
Eukaryotes: transcription elongation is closely related to rna processing. The rna molecule after transcription has exon and intron sequences. Needs to be modified on both ends and have introns removed. Allows different parts of a protein coding sequence to be joint together, thus letting higher eukaryotes make different proteins from the same gene. Key step in transcription initiation: phosphorylation of rna polymerase ii tail (ctd) It helps dissociate the rna polymerase ii from other proteins and lets new set of proteins to help the tail elongate. There is a 5" to 5" linkage between the 7 methyl guanosine to the rest of the rna (called a 5" to 5" triphosphate bridge) It holds many proteins close until they"re needed, helping speed up reactions. The mrna is made starting at 5" to 3". Contain instructions for many proteins b/c there"s no nucleus, the transcription and translation take place in the same area translation may begin even before transcription is finished.
