BIO230H1 Lecture Notes - Lecture 3: Circadian Rhythm, Repressilator, Repressor
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BIO230H1 Full Course Notes
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When repressor is bound to dna, it prevents transcription. Ligand = nutrient, waste, peptide, water, small molecules. You must also consider ligand, in addition to repressor/activator binding. Far upstream of gene (way before start site) Not only blocks cro, but also pulls down rna polymerase and tells to make more of itself - repressor. So now all cells now have a protein --> they remember way back when, their great great great grandmother got this transient signal. Stem cell: at beginning you tell it it"s a neuron, after this, all daughter cells are neurons. Example to help understand why this feed-forward circuit modulates sensitivity: Output = you punching that guy in the face. Someone annoys you, a is expressed, they annoy you a tiny bit more, a accumulated, and that leads to z expression. They annoy you a bit more, a accumulates enough to get b expressed. They annoy you even more, so b accumulates.
