N,N-DMT and 5-MeO-DMT are both very intense, short duration (just a few minutes) trips, while 4-AcO-DMT is a prodrug of 4-HO-DMT (psilocin), so very Mushroom-like.
Did you check the big threads about all three substances here, and the Erowid vaults already? Your question can easily be answered with a quick search, seriously!
That is a theory and has never been substantiated, from an anecdotal point of view 4-aco-dmt feels quite a bit different than mushrooms but SO SIMILAR at the same time.
There are a lot of similarities but enough differences for me to believe that if the prodrug theory is true, then there must be some sort of alternate activity as well besides the supposedly created psilocin.