小结原核生物RNA前体包含RNA和所有3 种rRNAs。rRNAs通过RNase III和RNase E 的作用从前体中释放
小结 原核生物RNA前体包含tRNA和所有3 种rRNAs。rRNAs通过RNase Ⅲ和RNase E 的作用从前体中释放
Transfer RNA processing Transfer RNA are made in all of cells as overly long precursors that must be processing by removing RNA at both ends. 。 Eukaryotes and prokaryotes tRNA processing are similar,but prokaryotes tRNA precursor contain one or more tRNAs. Cutting apart polycistronic precursors ·RNase III for cutting Forming mature 5'-ends Forming mature 3'-ends
Transfer RNA processing • Transfer RNA are made in all of cells as overly long precursors that must be processing by removing RNA at both ends. • Eukaryotes and prokaryotes tRNA processing are similar, but prokaryotes tRNA precursor contain one or more tRNAs. • Cutting apart polycistronic precursors • RNase III for cutting • Forming mature 5’-ends • Forming mature 3’-ends
Forming mature 5'-ends Figurel6.5 RNase p cut the signal RNase P- site of 5'end of tRNA precursor to form the mature 5'-end of tRNA
Forming mature 5’-ends RNase P cut the signal site of 5’end of tRNA precursor to form the mature 5’-end of tRNA. Figure16.5
RNase P RNase p have be found in both bacterium and eukaryotic nuclei. RNase p contain two subunits,one is protein (14kD)another one is RNA (M1 RNA;125kD). Both the protein and RNA parts of RNase p are required for RNase activity. Spinach(菠菜)chloroplast(叶绿体)RNase p appears to lack an RNA subunit
RNase P • RNase P have be found in both bacterium and eukaryotic nuclei. • RNase P contain two subunits, one is protein (14kD) another one is RNA (M1 RNA; 125kD). • Both the protein and RNA parts of RNase P are required for RNase activity. Spinach (菠菜)chloroplast (叶绿体)RNase P appears to lack an RNA subunit
The M1 RNA of E.Coli RNase p has enzymatic activity MI RNA RNase P Mg2+(mM):5102020303040405050 - H0 NH4CI(mM):1005050100501005010050100- 60 123456789101112 (tRNA pre)pTyr (rRNA as control)p4.5 Tyr (single tRNA)5'-Tyr Figur e16.6 kadatLmeRAnmceyosm8p8eae8rcenmece35oec19e3p.851.t4从
The M1 RNA of E.Coli RNase P has enzymatic activity M1 RNA RNase P (Single tRNA) (tRNA pre) (rRNA as control) Figur e16.6