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Transcription. Central Dogma Sense (codon) vs antisense (non-coding) Types of RNAs Structural genes vs regulatory genes RNA polymerases (I, II, III) Promoters Transcription factors Mechanism. The Central Dogma of Biology. DNA. Transcription. Reverse transcriptase. RNA.
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Transcription • Central Dogma • Sense (codon) vs antisense (non-coding) • Types of RNAs • Structural genes vs regulatory genes • RNA polymerases (I, II, III) • Promoters • Transcription factors • Mechanism
The Central Dogma of Biology DNA Transcription Reverse transcriptase RNA Translation Protein
3 classes of RNA Ribosomal 18S (16S) Components of ribosomes 28S (23S 5S Messenger Polycistronic (Bacteria) Monocystronic (Eukaryotes) Transfer 4S
SENSE VS ANTISENSE 5’ 3’ A T G C T C T G A C A T A C G A G A C T G T 3’ 5’ BASE COMPLEMENTARITY mRNA A U G C U C U G A C A RED STRAND IS SENSE STRAND GREEN STRAND IS ANTISENSE STRAND
Structural genes Regulator Gene Operator R O SG1 SG2 SG3 R-mRNA Repressor-inducer complex Polycistronic mRNA Translation Repressor Inducer prevents repressor from binding to promoter Proteins Basic Model of Gene Regulation in Bacteria
RNA Polymerase in Bacteriophage T7 Nontemplate (sense strand)
Control and Enhancer Sequences in Promoter • TATA box (Pribnow) • GC box • CCAAT box • Heat shock element • Serum response element • Glucocorticoid response element • Metal response elements • Homeodomains
TATA Box Start Site Promoter Sequences highlighting the TATA box
2 hexlix turns apart Location of Consensus Sequences on Non-template (coding) strand
Pre-transcription Complex
Factor independent Termination