As for the latter question, I looked into this, and I think the 2 day ‘on’ of YF expression is literally just the max time it can be expressed without deleterious effects. I think people haven’t investigated the ‘off’ cycle time as much. I suspect people are on the ‘the more reprogramming I can do, the better’ train up until recently, so that level of optimization likely is higher handing fruit.
From here: https://www.nature.com/articles/s41467-024-46020-5 ″The currently optimized method of partial reprogramming is the maturation phase partial reprogramming, which necessitates 13 days of continuous expression of Yamanaka factors in vitro...However, this optimized in vitro method may be highly damaging in in vivo models, as a continuous expression of Yamanaka factors for more than 2 days may have lethal effects in mice8,67. In vivo studies now focus on cyclic partial reprogramming....”
Great catch, dumb mistake on my part, fixed!
As for the latter question, I looked into this, and I think the 2 day ‘on’ of YF expression is literally just the max time it can be expressed without deleterious effects. I think people haven’t investigated the ‘off’ cycle time as much. I suspect people are on the ‘the more reprogramming I can do, the better’ train up until recently, so that level of optimization likely is higher handing fruit.
From here: https://www.nature.com/articles/s41467-024-46020-5
″The currently optimized method of partial reprogramming is the maturation phase partial reprogramming, which necessitates 13 days of continuous expression of Yamanaka factors in vitro...However, this optimized in vitro method may be highly damaging in in vivo models, as a continuous expression of Yamanaka factors for more than 2 days may have lethal effects in mice8,67. In vivo studies now focus on cyclic partial reprogramming....”