__ ▁mi R - 2 1 4 ▁is ▁a ▁verte br ate - specific ▁family ▁of ▁micro R NA ▁prec urs ors . ▁The ▁~ 2 2   n uc le ot ide ▁m ature ▁mi R NA ▁sequence ▁is ▁exc ised ▁from ▁the ▁prec ursor ▁hair pin ▁by ▁the ▁en zym e ▁Dic er . ▁This ▁sequence ▁then ▁associ ates ▁with ▁R IS C ▁which ▁effects ▁R NA ▁inter ference . ▁ ▁Origin ▁and ▁evolution ▁of ▁mi R - 2 1 4 ▁mi R - 2 1 4 ▁is ▁a ▁verte br ate - specific ▁mi R ▁family ▁that ▁poss esses ▁one ▁member ▁in ▁non - tele ost ▁verte br ates ▁and ▁two ▁members ▁in ▁tele ost ▁fish . ▁mi R - 2 1 4 ▁is ▁likely ▁to ▁have ▁emer ged ▁within ▁the ▁D nm 3 ▁gene ▁after ▁the ▁diver gence ▁of ▁j aw ed ▁and ▁j aw less ▁verte br ates ▁and ▁is ▁located ▁on ▁the ▁opposite ▁str and ▁of ▁an ▁intr on ▁of ▁D nm 3 ▁and ▁is ▁associated ▁in ▁an ▁expression ▁cluster ▁with ▁mi R - 1 9 9 . ▁ ▁Function ▁ ▁mi R - 2 1 4 ▁is ▁a ▁" mel ano - mi R ", ▁so - called ▁because ▁it ▁is ▁thought ▁to ▁encou rage ▁the ▁met ast asis ▁of ▁mel an oma . ▁Specifically , ▁the ▁m ature ▁micro R NA ▁exc ised ▁from ▁mi R - 2 1 4 ▁is ▁predicted ▁to ▁target ▁two ▁activ ating ▁protein ▁ 2 ▁trans cription ▁factors , ▁bringing