The number of adenine repeats that confer functional properties is quite variable but it definitely needs to be more than "just 1". I've seen anywhere from 25-250 used in designed plasmids. The exact number people use in their engineered sequence is based on a number of factors, not all of them scientific in nature (e.g. companies charge per basepair synthesize a bespoke polypeptide; e.g. you copied the sequence from a previous clone into ApE and that sequence used 30 repeats and worked fine).
Iirc there's a protein that adds 12-15 slowly then another protein comes in and adds another 200+ when it detects the start of the tail. Not sure about the details about how or why it stops tho. At least when considering mRNA getting prepped for nuclear export
In this case it probably works most reliably with around this number of As, and less/more would decrease reliability, butnitmwould still be functional.
With more As you risk running into the upper limit on sequence length for the virus shell and with less you run the risk of quicker degradation and not enough expression
subroutine|3 years ago
kevviiinn|3 years ago
unknown|3 years ago
[deleted]
kolinko|3 years ago
Most of genetics is like that.
kevviiinn|3 years ago