BIO230H1 Lecture Notes - Lecture 2: Lambda Phage, Lac Repressor, Rna-Seq
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BIO230H1 Full Course Notes
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Both: occur when both are bound to dna. If something binds to dna, it likely has a helix-turn-helix motif. Top right = exists, but no example given in class. Activator protein recruits rna polymerase to the promoter to activate transcription. Gene regulatory elements are typically close to transcriptional start site, but not always. Competition between rna polymerase and repressor protein for promoter binding. Some reg elements are distant from start site and influence transcription via dna looping. For prokaryotes, but general mechanism is for eukaryotes. Cis-reg seq is very far, so it folds up to let protein interact. Positive and neg regulatory mechanisms work together to regulate lifestyles of bacteriophage lambda. Below: red = dna ; green = protein. Proteins help circularization but not needed for this course. Can exist as one of two states of bacteria. Lambda dna is in the regular dna, so viral dna is passed on.
