transcription vs translation
DESCRIPTION
Transcription vs Translation. Central Dogma. Translation. Transcription. Chargaff’s Rule. States that base ratio is 1:1 A=T CΞG Therefore if there are 300 Adenines there should also be 300 Thymines in DNA. Transcription. - PowerPoint PPT PresentationTRANSCRIPT
Transcription vs Translation
Central Dogma
TranscriptionTranslation
Chargaff’s RuleStates that base ratio is 1:1A=TCΞGTherefore if there are 300 Adenines there should also be 300 Thymines in DNA
TranscriptionInitiation – RNA polymerase attaches to the promoter region on the DNA and begins to unzip the DNA. Promoter normally contains TATA box, sequence of T-A-T-A
TranscriptionElongation occurs as RNA polymerase unzips the DNA and assembles RNA nucleotides using one strand of the DNA as a template. This occurs in the 5’ 3’ direction
TranscriptionTermination occurs when the RNA polymerase reaches a special sequence of nucleotides that servers as a termination point. In eukaryotes the termination region is often AAAAAAAAAAA.
mRNA processingBefore mRNA can leave the nucleus several things happen:
5’ cap is added, cap is guanine nucleotide with 2 extra phosphatesPoly A tail added to 3’ end. Tail has about 200 adenine nucleotides.RNA splicing – introns are removed, exons are spliced together. Small nuclear ribonucleoproteins or snRNP’s delete the introns Alternative splicing
RNA splicingAppropriately joined
Protein
IntronsExons
TranslationInitiation begins when the small ribosomal subunit attaches near the 5’ end of mRNAA tRNA carrying an amino acid attaches to the mRNA at the start codon AUG. The large ribosomal subunit attaches to the mRNA forming a complete ribosomeElongation begins when the next tRNA binds
Translation