Polypyrimidine　tract-binding　protein　(PTB),　an　RNA-binding　protein,　is　involved　in　the　regulation　of　diverse　processes　in　mRNA　metabolism.　However,　the　allosteric　modulation　of　its　binding　with　RNA　remains　unclear.　We　explore　the　dynamic　characteristics　of　PTB　RNA　recognition　motif　1　(RRM1)　in　its　RNA-free　and　wild-type/　mutant　RNA-bound　states　to　understand　the　issues　using　molecular　dynamics　(MD)　simulation,　perturbation　response　scanning　(PRS)　and　protein　structure　network　(PSN)　models.　It　is　found　that　RNA　binding　strengthens　RRM1　stability,　while　L151G　mutation　in　alpha　3　helix　far　away　from　the　interface　makes　the　complex　unstable.　The　latter　is　caused　by　long-distance　dynamic　couplings,　which　makes　intermolecular　electrostatic　and　entropy　en-ergies　unfavorable.　The　weakened　couplings　between　interface　13　sheets　and　C-terminal　parts　upon　mutation　reveal　RNA　recognition　is　co-regulated　by　these　regions.　Interestingly,　PRS　analysis　reveals　the　allostery　caused　by　the　perturbation　on　alpha　3　helix　has　already　been　pre-encoded　in　the　equilibrium　dynamics　of　the　protein　structure.　PSN　analysis　shows　the　details　of　the　allosteric　signal　transmission,　revealing　the　necessity　of　strong　couplings　between　alpha　3　helix　and　interface　for　maintaining　the　high　binding　affinity.　This　study　sheds　light　on　the　mechanisms　of　PTB　allostery　and　RNA　recognition　and　can　provide　important　information　for　drug　design.