Biomaterial Database

Capping signals correspond to the 5' end in four eukaryotic small RNAs containing gamma-monomethylphosphate cap structure. 1994

G Shumyatsky, and S Shimba, and R Reddy

Department of Pharmacology, Baylor College of Medicine, Houston, TX 77030.

In eukaryotic cells, the gamma-monomethylphosphate cap structure has been identified in four small RNAs, namely, U6, 7SK, B2, and plant U3 RNAs. In this study, we show that in the case of 7SK and B2, as well as in plant U3 RNAs, the 5' stem-loop followed by a short single-stranded region serves as the capping signal. We previously showed that the nucleotides 1-25 of mouse U6 snRNA, also comprised of a stem-loop followed by a short single-stranded region, function as the capping signal. These data show that capping signals in all four RNAs have common features. The length of the stem-loop among these capped RNAs varied from 20 to 108 nucleotides, with no significant variation in the capping efficiency. In addition to the capping signal, we also observed a minimum RNA length requirement of about 15-25 nucleotides following the stem-loop for efficient capping in vitro. The capping signal in plant U3 snRNA corresponds to the additional 5' stem-loop found in U3 RNAs from plants and lower eukaryotes but absent in U3 RNA from higher animals. Consistent with this observation, the human U3 RNA that lacks the additional 5' stem-loop was not a suitable substrate for capping when compared to U6 snRNA.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009690	Nucleic Acid Conformation	The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.	DNA Conformation,RNA Conformation,Conformation, DNA,Conformation, Nucleic Acid,Conformation, RNA,Conformations, DNA,Conformations, Nucleic Acid,Conformations, RNA,DNA Conformations,Nucleic Acid Conformations,RNA Conformations
D010755	Organophosphates	Carbon-containing phosphoric acid derivatives. Included under this heading are compounds that have CARBON atoms bound to one or more OXYGEN atoms of the P(	Organophosphate,Phosphates, Organic,Phosphoric Acid Esters,Organopyrophosphates,Acid Esters, Phosphoric,Esters, Phosphoric Acid,Organic Phosphates
D010944	Plants	Multicellular, eukaryotic life forms of kingdom Plantae. Plants acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations. It is a non-taxonomical term most often referring to LAND PLANTS. In broad sense it includes RHODOPHYTA and GLAUCOPHYTA along with VIRIDIPLANTAE.	Plant
D011061	Poly A	A group of adenine ribonucleotides in which the phosphate residues of each adenine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.	Adenine Polynucleotides,Polyadenylic Acids,Poly(rA),Polynucleotides, Adenine
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D012315	RNA Caps	Nucleic acid structures found on the 5' end of eukaryotic cellular and viral messenger RNA and some heterogeneous nuclear RNAs. These structures, which are positively charged, protect the above specified RNAs at their termini against attack by phosphatases and other nucleases and promote mRNA function at the level of initiation of translation. Analogs of the RNA caps (RNA CAP ANALOGS), which lack the positive charge, inhibit the initiation of protein synthesis.	RNA Cap,5' Capped RNA,5' mRNA Cap Structure,Cap, RNA,Caps, RNA,RNA, 5' Capped