exonuclease activity. RNase D can recognize structurally altered tRNA molecules. The enzyme acts poorly on intact tRNA and is inactive with the synthetic polyribonucleotides, poly(A), poly(U), or double-stranded poly(A)*poly(U). The enzyme acts on diesterase-treated tRNA, but relatively poorly on intact tRNA. RNase D does not attack ribosomal RNA
alteration of the 3'-terminal base has no effect on the rate of hydrolysis, whereas modification of the 3'-terminal sugar has a major effect. tRNA terminating with a 3'-phosphate is completely inactive as a substrate. The rate of hydrolysis of intact tRNA is very slow compared to tRNAs containing extra residues or compared to tRNAs from which part of the -C-C-A sequence has been removed. Oxidation of the terminal sugar, reduction of the dialdehyde with borohydride, or removal of the terminal AMP from intact tRNA increase the activity of the substrate. Addition of a second -C-C-A sequence gives an active substrate indicating that the relative resistance of intact tRNA to RNase D hydrolysis is not due to the sequence per se but to the structural environment of the 3'-terminus. The enzyme is an exonuclease which initiates hydrolysis at the 3'-terminus and removes 5'-mononucleotides in a random fashion
in vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs that provide the sequence information for RNA editing
in vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs that provide the sequence information for RNA editing
in vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs that provide the sequence information for RNA editing
in vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs that provide the sequence information for RNA editing
TbRND shares sequence similarity with RNase D family enzymes but differs from all reported members of this family in possessing a CCHC zinc finger domain
TbRND shares sequence similarity with RNase D family enzymes but differs from all reported members of this family in possessing a CCHC zinc finger domain
TbRND depletion results in gRNA tails extended by 2-3 nucleotides on average. Second, overexpression of wild-type but not catalytically inactive TbRND results in a substantial decrease in the total gRNA population and a consequent inhibition of RNA editing. The observed effects on the gRNA population are specific as rRNAs, which are also 3'-uridylated, are unaffected by TbRND depletion or overexpression, phenotypes, overview
TbRND depletion results in gRNA tails extended by 2-3 nucleotides on average. Second, overexpression of wild-type but not catalytically inactive TbRND results in a substantial decrease in the total gRNA population and a consequent inhibition of RNA editing. The observed effects on the gRNA population are specific as rRNAs, which are also 3'-uridylated, are unaffected by TbRND depletion or overexpression, phenotypes, overview
TbRND functions in guide RNA metabolism in vivo, TbRND is a 3' to 5' exoribonuclease that functions highly specific to the mitochondrion of trypanosomes. In vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs that provide the sequence information for RNA editing
TbRND functions in guide RNA metabolism in vivo, TbRND is a 3' to 5' exoribonuclease that functions highly specific to the mitochondrion of trypanosomes. In vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs that provide the sequence information for RNA editing
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
1.6 A resolution crystal structure. Hanging-drop technique was used for subsequent crystal optimizations. Each drop contains equal volumes of protein and reservoir solution. RNase D protein crystallizes in the presence of 2.02.5 M ammonium sulfate and various buffer conditions. The crystals used here are grown with a reservoir containing 2.22.3 sulfate and 0.1 M HEPES (pH 7.0). Crystals of RNase D usually appeared overnight under these conditions. Crystals grow to full size in 27 days, with a maximum size of over 1 mm in each dimension. Zn2+ -containing crystals are grown with 1 mM ZnSO4 included in the reservoir prior to drop setup. Mercury(II) derivatives are prepared by soaking RNase D crystals (without Zn2+) overnight in the mother liquor containing 5 mM HgSO4
ORF Tb09.211.3670, DNA and amino acid sequence determination and analysis, generation of pRND-MHT for tetracycline-regulated expression of TbRND with a C-terminal myc-His6-TAP tag in Trypanosoma brucei, expression of N-terminally GST- and His-tagged TbRND in Escherichia coli