▁cell ▁line age , ▁expressed ▁in ▁Schw ann ▁cell ▁prec urs ors ▁after ▁differenti ating ▁from ▁migr ating ▁neural ▁cr est ▁cells ▁within ▁the ▁developing ▁emb ry o . ▁ ▁K ro x - 2 0 ▁▁ ▁Several ▁important ▁trans cription ▁factors ▁are ▁also ▁expressed ▁and ▁involved ▁at ▁various ▁stages ▁in ▁development ▁changing ▁the ▁features ▁on ▁the ▁Schw ann ▁cells ▁from ▁an ▁imm ature ▁to ▁m ature ▁state . ▁One ▁ind isp ens able ▁trans cription ▁factor ▁expressed ▁during ▁the ▁my el ination ▁process ▁is ▁K ro x - 2 0 . ▁It ▁is ▁a ▁general ▁z inc - f inger ▁trans cription ▁factor ▁and ▁is ▁expressed ▁in ▁the ▁rh omb om eres ▁ 3 ▁and ▁ 5 . ▁ ▁K ro x - 2 0 ▁is ▁considered ▁as ▁one ▁of ▁the ▁master ▁regul ators ▁of ▁P NS ▁my el ination ▁and ▁is ▁important ▁in ▁driving ▁trans cription ▁of ▁specific ▁struct ural ▁prote ins ▁in ▁the ▁my elin . ▁It ▁has ▁been ▁shown ▁to ▁control ▁a ▁set ▁of ▁gen es ▁responsible ▁for ▁inter fer ing ▁with ▁this ▁feature ▁in ▁the ▁ax on ▁changing ▁it ▁from ▁a ▁pro - my elin ating ▁to ▁my elin ating ▁state . ▁In ▁this ▁way , ▁in ▁K ro x - 2 0 ▁double ▁knock ▁out ▁m ice , ▁it ▁has ▁been ▁recorded ▁that ▁h ind bra in ▁segment ation ▁is ▁affected ▁as ▁well ▁as ▁my el ination ▁of ▁Schw ann ▁cell ▁associated ▁ax ons . ▁Indeed , ▁in ▁these ▁m ice , ▁the ▁Schw ann ▁cells ▁are