A conserved polypeptide motif that can be recognized by both Fizzy/Cdc20- and FZR/Cdh1-activated anaphase-promoting complex/cyclosome (APC/C) and targets a protein for ubiquitination and subsequent degradation by the APC/C. The consensus sequence is RXXLXXXXN.
A sequence variant that does not affect protein function. Silent mutations may occur in genic ( CDS, UTR, intron etc) and intergenic regions. Silent mutations may have affects on processes such as splicing and regulation.
A DNA motif to which the S. pombe Sap1 protein binds. The consensus sequence is 5'-TARGCAGNTNYAACGMG-3'; it is found at the mating type locus, where it is important for mating type switching, and at replication fork barriers in rDNA repeats.
Dictyostelium intermediate repeat sequence (DIRS) retrotransposons are members of the YR_retrotransposon (SO:0002286) superfamily with the following protein domains: RT, RH, YR, and MT. RT is a reverse transcriptase. RH is RNAse H. YR is tyrosine recombinase. MT is DNA N-6-adenine-methyltransferase.
MERGED DEFINITION:
TARGET DEFINITION: A promoter element with consensus sequence TGACGTCA; bound by the ATF/CREB family of transcription factors.
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SOURCE DEFINITION: A promoter element that contains a core sequence TGACGT, bound by a protein complex that regulates transcription of genes encoding PKA pathway components.
A cis-regulatory element, conserved sequence YYC+1TTTYY, and spans -2 to +6 relative to +1 TSS. It is present in most ribosomal protein genes in Drosophila and mammals but not in the yeast Saccharomyces cerevisiae. Resembles the initiator (TCAKTY in Drosophila) but functionally distinct from initiator.
LTR retrotransposons in the Copia superfamily contain elements coding for specific proteins in this order: GAG, AP, INT, RT, RH. GAG is a structural protein for virus-like particles. AP is aspartic proteinase. INT is a DDE integrase. RT is a reverse transcriptase. RH is RNAse H.
LTR retrotransposons in the Gypsy superfamily contain elements coding for specific proteins in this order: GAG, AP, RT, RH, INT. GAG is a structural protein for virus-like particles. AP is aspartic proteinase. INT is a DDE integrase. RT is a reverse transcriptase. RH is RNAse H.
Ngaro retrotransposons are members of the YR_retrotransposon (SO:0002286) superfamily with the following protein domains: RT, RH, YR. RT is a reverse transcriptase. RH is RNAse H. YR is Tyrosine recombinase. Inverted terminal repeats (ITRs) in Ngaro are arranged in A-pol-B-A-B order where A and B represent ITRs.
The Rev response element (RRE) is encoded within the HIV-env gene. Rev is an essential regulatory protein of HIV that binds an internal loop of the RRE leading, encouraging further Rev-RRE binding. This RNP complex is critical for mRNA export and hence for expression of the HIV structural proteins.
A family of RNAs are found as part of the enigmatic vault ribonucleoprotein complex. The complex consists of a major vault protein (MVP), two minor vault proteins (VPARP and TEP1), and several small untranslated RNA molecules. It has been suggested that the vault complex is involved in drug resistance.
A C-terminus protein motif (CAAX) serving as a post-translational prenylation site modified by the attachment of either a farnesyl or a geranyl-geranyl group to a cysteine residue. Farnesyltransferase recognizes CaaX boxes where X = M, S, Q, A, or C, whereas Geranylgeranyltransferase I recognizes CaaX boxes with X = L or E.
VIPER retrotransposons are members of the YR_retrotransposon (SO:0002286 superfamily with protein domains: RT, RH, YR. RT is a reverse transcriptase. RH is RNAse H. YR is Tyrosine recombinase. Inverted terminal repeats (ITRs) in VIPER are arranged in A-pol-B-A-B order where A and B represent ITRs. VIPER is only found in kinetoplastida genomes.
U5 RNA is a component of both types of known spliceosome. The precise function of this molecule is unknown, though it is known that the 5' loop is required for splice site selection and p220 binding, and that both the 3' stem-loop and the Sm site are important for Sm protein binding and cap methylation.
U4 small nuclear RNA (U4 snRNA) is a component of the major U2-dependent spliceosome. It forms a duplex with U6, and with each splicing round, it is displaced from U6 (and the spliceosome) in an ATP-dependent manner, allowing U6 to refold and create the active site for splicing catalysis. A recycling process involving protein Prp24 re-anneals U4 and U6.
This is used for non-spliced EST clusters that have polyA features. This category has been specifically created for the ENCODE project to highlight regions that could indicate the presence of protein coding genes that require experimental validation, either by 5' RACE or RT-PCR to extend the transcripts, or by confirming expression of the putatively-encoded peptide with specific antibodies.
A sequence element characteristic of the promoters of snRNA genes transcribed by RNA polymerase II or by RNA polymerase III. Located between -45 and -60 relative to the TSS. The human PSE_motif consensus sequence is TCACCNTNA(C|G)TNAAAAG(T|G). The basal transcription factor, snRNA-activating protein complex (SNAPc), binds the PSE_motif and is required for the transcription of both RNA polymerase II and III transcribed small-nuclear RNA genes.
A beta strand describes a single length of polypeptide chain that forms part of a beta sheet. A single continuous stretch of amino acids adopting an extended conformation of hydrogen bonds between the N-O and the C=O of another part of the peptide. This forms a secondary protein structure in which two or more extended polypeptide regions are hydrogen-bonded to one another in a planar array.
LTR retrotransposons in the Bel-Pao superfamily are similar to LTRs in the Gypsy and Retrovirus superfamilies. Mainly described in metazoan genomes, this superfamily contain elements coding for specific proteins in this order: GAG, AP, RT, RH and INT. GAG is a structural protein for virus-like particles. AP is aspartic proteinase. INT is a DDE integrase. RT is a reverse transcriptase. RH is RNAse H.
LTR retrotransposons in the retrovirus superfamily are similar to LTR retrotransposons in the Gypsy and Bel-Pao superfamilies. Mainly described in vertebrate animals, this superfamily contain elements coding for specific proteins in this order: GAG, AP, RT, RH, INT, and ENV. GAG is a structural protein for virus-like particles. AP is aspartic proteinase. INT is a DDE integrase. RT is a reverse transcriptase. RH is RNAse H. ENV is envelop protein.
The RNA component of Ribonuclease P (RNase P), a ubiquitous endoribonuclease, found in archaea, bacteria and eukarya as well as chloroplasts and mitochondria. Its best characterized activity is the generation of mature 5 prime ends of tRNAs by cleaving the 5 prime leader elements of precursor-tRNAs. Cellular RNase Ps are ribonucleoproteins. RNA from bacterial RNase Ps retains its catalytic activity in the absence of the protein subunit, i.e. it is a ribozyme. Isolated eukaryotic and archaeal RNase P RNA has not been shown to retain its catalytic function, but is still essential for the catalytic activity of the holoenzyme. Although the archaeal and eukaryotic holoenzymes have a much greater protein content than the bacterial ones, the RNA cores from all the three lineages are homologous. Helices corresponding to P1, P2, P3, P4, and P10/11 are common to all cellular RNase P RNAs. Yet, there is considerable sequence variation, particularly among the eukaryotic RNAs.
The incorporation of selenocysteine into a protein sequence is directed by an in-frame UGA codon (usually a stop codon) within the coding region of the mRNA. Selenoprotein mRNAs contain a conserved secondary structure in the 3' UTR that is required for the distinction of UGA stop from UGA selenocysteine. The selenocysteine insertion sequence (SECIS) is around 60 nt in length and adopts a hairpin structure which is sufficiently well-defined and conserved to act as a computational screen for selenoprotein genes.
An enterobacterial RNA that binds the CsrA protein. The CsrB RNAs contain a conserved motif CAGGXXG that is found in up to 18 copies and has been suggested to bind CsrA. The Csr regulatory system has a strong negative regulatory effect on glycogen biosynthesis, glyconeogenesis and glycogen catabolism and a positive regulatory effect on glycolysis. In other bacteria such as Erwinia caratovara the RsmA protein has been shown to regulate the production of virulence determinants, such extracellular enzymes. RsmA binds to RsmB regulatory RNA which is also a member of this family.
A tmRNA liberates a mRNA from a stalled ribosome. To accomplish this part of the tmRNA is used as a reading frame that ends in a translation stop signal. The broken mRNA is replaced in the ribosome by the tmRNA and translation of the tmRNA leads to addition of a proteolysis tag to the incomplete protein enabling recognition by a protease. Recently a number of permuted tmRNAs genes have been found encoded in two parts. TmRNAs have been identified in eubacteria and some chloroplasts but are absent from archeal and Eukaryote nuclear genomes.
By definition, minigenes are short open-reading frames (ORF), usually encoding approximately 9 to 20 amino acids, which are expressed in vivo (as distinct from being synthesized as peptide or protein ex vivo and subsequently injected). The in vivo synthesis confers a distinct advantage: the expressed sequences can enter both antigen presentation pathways, MHC I (inducing CD8+ T- cells, which are usually cytotoxic T-lymphocytes (CTL)) and MHC II (inducing CD4+ T-cells, usually 'T-helpers' (Th)); and can encounter B-cells, inducing antibody responses. Three main vector approaches have been used to deliver minigenes: viral vectors, bacterial vectors and plasmid DNA.
Group II introns are found in rRNA, tRNA and mRNA of organelles in fungi, plants and protists, and also in mRNA in bacteria. They are large self-splicing ribozymes and have 6 structural domains (usually designated dI to dVI). A subset of group II introns also encode essential splicing proteins in intronic ORFs. The length of these introns can therefore be up to 3kb. Splicing occurs in almost identical fashion to nuclear pre-mRNA splicing with two transesterification steps. The 2' hydroxyl of a bulged adenosine in domain VI attacks the 5' splice site, followed by nucleophilic attack on the 3' splice site by the 3' OH of the upstream exon. Protein machinery is required for splicing in vivo, and long range intron to intron and intron-exon interactions are important for splice site positioning. Group II introns are further sub-classified into groups IIA and IIB which differ in splice site consensus, distance of bulged A from 3' splice site, some tertiary interactions, and intronic ORF phylogeny.
U3 snoRNA is a member of the box C/D class of small nucleolar RNAs. The U3 snoRNA secondary structure is characterised by a small 5' domain (with boxes A and A'), and a larger 3' domain (with boxes B, C, C', and D), the two domains being linked by a single-stranded hinge. Boxes B and C form the B/C motif, which appears to be exclusive to U3 snoRNAs, and boxes C' and D form the C'/D motif. The latter is functionally similar to the C/D motifs found in other snoRNAs. The 5' domain and the hinge region act as a pre-rRNA-binding domain. The 3' domain has conserved protein-binding sites. Both the box B/C and box C'/D motifs are sufficient for nuclear retention of U3 snoRNA. The box C'/D motif is also necessary for nucleolar localization, stability and hypermethylation of U3 snoRNA. Both box B/C and C'/D motifs are involved in specific protein interactions and are necessary for the rRNA processing functions of U3 snoRNA.
A gene that codes for U3_snoRNA. U3 snoRNA is a member of the box C/D class of small nucleolar RNAs. The U3 snoRNA secondary structure is characterised by a small 5' domain (with boxes A and A'), and a larger 3' domain (with boxes B, C, C', and D), the two domains being linked by a single-stranded hinge. Boxes B and C form the B/C motif, which appears to be exclusive to U3 snoRNAs, and boxes C' and D form the C'/D motif. The latter is functionally similar to the C/D motifs found in other snoRNAs. The 5' domain and the hinge region act as a pre-rRNA-binding domain. The 3' domain has conserved protein-binding sites. Both the box B/C and box C'/D motifs are sufficient for nuclear retention of U3 snoRNA. The box C'/D motif is also necessary for nucleolar localization, stability and hypermethylation of U3 snoRNA. Both box B/C and C'/D motifs are involved in specific protein interactions and are necessary for the rRNA processing functions of U3 snoRNA.
The signal recognition particle (SRP) is a universally conserved ribonucleoprotein. It is involved in the co-translational targeting of proteins to membranes. The eukaryotic SRP consists of a 300-nucleotide 7S RNA and six proteins: SRPs 72, 68, 54, 19, 14, and 9. Archaeal SRP consists of a 7S RNA and homologues of the eukaryotic SRP19 and SRP54 proteins. In most eubacteria, the SRP consists of a 4.5S RNA and the Ffh protein (a homologue of the eukaryotic SRP54 protein). Eukaryotic and archaeal 7S RNAs have very similar secondary structures, with eight helical elements. These fold into the Alu and S domains, separated by a long linker region. Eubacterial SRP is generally a simpler structure, with the M domain of Ffh bound to a region of the 4.5S RNA that corresponds to helix 8 of the eukaryotic and archaeal SRP S domain. Some Gram-positive bacteria (e.g. Bacillus subtilis), however, have a larger SRP RNA that also has an Alu domain. The Alu domain is thought to mediate the peptide chain elongation retardation function of the SRP. The universally conserved helix which interacts with the SRP54/Ffh M domain mediates signal sequence recognition. In eukaryotes and archaea, the SRP19-helix 6 complex is thought to be involved in SRP assembly and stabilizes helix 8 for SRP54 binding.
