#Id: 1855
#Unit 3. Fundamental Processes
Start point, is the first base of mRNA to be A
• Initiator (Inr) is Py2CAPy5, where Py stands for any pyrimidine. The Inr is contained between positions -3 and +5.
• TATA box, usually located, 25 bp upstream in its location at -25
• The exception is in yeast, where the TATA box is more typically found at -90.