Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.3 (RNase T1)
 1,228 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new rapid microassay for RNase is based on the extraction of the products of the degradation of aminoacyl-tRNA into ethyl acetate. The substrate, for example, f[3H]Met-tRNA, is not soluble in ethyl acetate but the product f[3H]Met-nucleotide is extracted with high efficiency over a wide range of pH in phosphate buffer of high ionic strength. The limit digest of f[3H]Met-tRNA by RNase T1 in which the minimum-sized product should be f[3H]Met-hexanucleotide is also soluble in ethyl acetate. The assay is sensitive to 0.05 pg of RNase A, has a very low background, and is linear with enzyme concentration. The most economic substrate is unfractionated tRNA containing a small concentration of the radiolabeled aminoacyl-tRNA.
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PMID:A ribonuclease assay: separation of product from undegraded aminoacyl-transfer RNA substrate. 656 Sep 99

tRNA is best known for its function as amino acid carrier in the translation process, using the anticodon loop in the recognition process with mRNA. However, the impact of tRNA on cell function is much wider, and mutations in tRNA can lead to a broad range of diseases. Although the cloverleaf structure of tRNA is well-known based on X-ray-diffraction studies, little is known about the dynamics of this fold, the way structural dynamics of tRNA is influenced by the modified nucleotides present in tRNA, and their influence on the recognition of tRNA by synthetases, ribosomes, and other biomolecules. One of the reasons for this is the lack of good synthetic methods to incorporate modified nucleotides in tRNA so that larger amounts become available for NMR studies. Except of 2'-O-methylated nucleosides, only one other sugar-modified nucleoside is present in tRNA, i.e., 2'-O-beta-D-ribofuranosyl nucleosides. The T loop of tRNA often contains charged modified nucleosides, of which 1-methyladenosine and phosphorylated disaccharide nucleosides are striking examples. A protecting-group strategy was developed to introduce 1-methyladenosine and 5''-O-phosphorylated 2'-O-(beta-D-ribofuranosyl)-beta-D-ribofuranosyladenine in the same RNA fragment. The phosphorylation of the disaccharide nucleoside was performed after the assembly of the RNA on solid support. The modified RNA was characterized by mass-spectrometry analysis from the RNase T1 digestion fragments. The successful synthesis of this T loop of the tRNA of Schizosaccharomyces pombe initiator tRNA(Met) will be followed by its structural analysis by NMR and by studies on the influence of these modified nucleotides on dynamic interactions within the complete tRNA.
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PMID:Synthesis of RNA containing O-beta-D-ribofuranosyl-(1''-2')-adenosine-5''-phosphate and 1-methyladenosine, minor components of tRNA. 1719 97