| This course is part of a series taught by Kevin Ahern at Oregon State University on General Biochemistry. For more information about online courses go to ecampus.oregonstate.edu for the rest of the courses see www.youtube.com 1. Transcription is the process where RNA is made using DNA as a template. Students should ABSOLUTELY not mix up or misuse the terms DNA Replication, Transcription, and Translation. 2. RNA polymerization requires an enzyme called RNA polymerase. It can start a chain without a primer, incorporates nucleotides into a growing chain in the 5' to 3' direction using phosphodiester bonds, and uses ATP, GTP, CTP, and UTP as starting compounds. The product of RNA polymerization is called a transcript. 3. The 5' -most nucleotide in RNA has three phosphates on it. All other nucleotides in RNA have only the single phosphate of a phosphodiester bond. Synthesis of the phosphodiester bond arises from nucleophilic attack of the 3' oxygen on the internal phosphate (closest to carbon 5 of the ribose) of the incoming 5' nucleotide. 4. Cells have three main types of RNA - mRNA (carries message to be translated into protein), tRNA (carries amino acids to ribosomes for incorporation into protein), and rRNA (components of ribosomes). 5. In E. coli, all of the RNAs are made by a single polymerase, known as RNA Polymerase. Eukaryotic cells have three RNA polymerases - RNA Polymerase I (rRNAs), RNA Polymerase II (mRNAs and snRNAs), and RNA Polymerase III (tRNAs). 6. E. coli ... |
