RNA and protein synthesi2

RNA and protein synthesi2 - = The identity of the...

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RNA and protein synthesis, the genetic code Transcription can be defined as the synthesis of a complementary strand of RNA from a DNA template (Tortora Fig 8.8) - There are three kinds of RNA is cells. In order of abundance, these are = ribosomal RNA (rRNA) is an important structural and functional component of ribosomes, the site of protein synthesis = transfer RNA (tRNA) is the "adapter" molecule that links nucleotide base sequence to amino acid sequence = messenger RNA (mRNA) encodes proteins - Although we tend to think of mRNAs in discussing transcription (since they then go on to be translated), synthesis of rRNAs and tRNAs occurs by the same mechanism - Synthesis of RNA by transcription is very similar to leading strand synthesis of DNA during replication = Free ribonucleotides are added to a growing strand in a 5' to 3' direction
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Unformatted text preview: = The identity of the nucleotides added is determined by base pairing with nucleotides in the DNA template strand = In RNA synthesis, uracil is added to a growing strand to pair with adenine, rather than thymine, which pairs with adenine in DNA- Only one strand of DNA in a given "gene" serves as the template- Transcription is catalyzed by the enzyme RNA polymerase- In addition to the sequence that is transcribed into an RNA sequence, the DNA sequence making up a gene contains additional information = The region where RNA polymerase binds to DNA to initiate transcription is known as the promoter site = The terminator site serves to signal the end point for transcription, where RNA polymerase is released from the DNA...
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This note was uploaded on 01/24/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.

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