Biochemistry 2280A Lecture : Regulation of Gene Expression
Document Summary
Some genes are transcribed more so than others. 1. some genes have better -10 and -35 sequences than othe genes. 10 and -35 are not created equal, some promoters are better than others. Promoter can t change -10 and -35, it is what it is can t change its static. Some promotors don t bind rna polymerase very well; so they arent expressed as much (-10 and -35 arent very good). A cell cant change what is in the promoter in real time (only evolutionary). There is more than one sigma factor each recognizes different promoters. Nitrogen 54 = nitrogen metabolism or sigma hs which is heat shock. Different sigma factors = controlling of different groups of genes. We talked about sigma 70, which is the hosuekeeping sigmar. egocnize -10 and -35. those genes are regualted by sigma 70. Some genes use specialized sigma factors are are controled by diff sigma fators. Theres also sigma 54 which is involved in nitrogen metabolism.