cofactor:Binds 2 magnesium ions per subunit.,enzyme regulation:Although it can bind simultaneously with SLBP to the 3-end of histone mRNA, the presence of SLBP prevents the exonuclease activity.,function:RNA exonuclease that binds to the 3-end of histone mRNAs and probably degrades them, suggesting that it plays an essential role in histone mRNA decay after replication. Also able to degrade the 3-overhangs of short interfering RNAs (siRNAs) in vitro, suggesting a possible role as regulator of RNA interference (RNAi). Required for 5.8S rRNA 3-end processing.,sequence caution:Translated as Leu.,similarity:Contains 1 exonuclease domain.,similarity:Contains 1 SAP domain.,subunit:Binds with high affinity to the stem-loop structure of replication-dependent histone pre-mRNAs. Requires the 5-ACCCA-3 sequence present in stem-loop structure. Able to bind other mRNAs. Binds to 40S and 60S ribosomal subunits and to 80S assembled ribosomes. Also binds to 5.8s ribosomal RNA.,cofactor:Binds 2 magnesium ions per subunit.,enzyme regulation:Although it can bind simultaneously with SLBP to the 3-end of histone mRNA, the presence of SLBP prevents the exonuclease activity.,function:RNA exonuclease that binds to the 3-end of histone mRNAs and probably degrades them, suggesting that it plays an essential role in histone mRNA decay after replication. Also able to degrade the 3-overhangs of short interfering RNAs (siRNAs) in vitro, suggesting a possible role as regulator of RNA interference (RNAi). Required for 5.8S rRNA 3-end processing.,sequence caution:Translated as Leu.,similarity:Contains 1 exonuclease domain.,similarity:Contains 1 SAP domain.,subunit:Binds with high affinity to the stem-loop structure of replication-dependent histone pre-mRNAs. Requires the 5-ACCCA-3 sequence present in stem-loop structure. Able to bind other mRNAs. Binds to 40S and 60S ribosomal subunits and to 80S assembled ribosomes. Also binds to 5.8s ribosomal RNA.,
