PTHrP, SOX9, and the reason why estrogen actually closes growth plates.

james said
cxxc5

Directly effects the Wnt/B-catenin signaling pathway which over time causes SOX9 to go down (via the making of RUNX2, MEF2C/MEF2D, etc) as SOX9 cannot fully inhibit it.

james said
There are other factors that actual “close” plates

Yes, but the PTHrP levels are the main bottle neck for most people.

james said
Estrogen is the main mediator of senescence

Mainly due to competing with PTHrP levels.

james said
And obviously as you age cells lose their proliferative capacity, which is why most people don’y grow as much after bone age 15

It's more nuanced than just this. It's more than just loss of proliferative capacity due to puberty affecting hormones.

james said
At our ages runx2 should be LOW as well.

Should they not be high if anything?