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Definition
 
enEnglish
Alternative Splicing definition: A process whereby multiple RNA transcripts are generated from a single gene. Alternative splicing involves the splicing together of other possible sets of EXONS during the processing of some, but not all, transcripts of the gene. Thus a particular exon may be connected to any one of several alternative exons to form a mature RNA. The alternative forms of mature MESSENGER RNA produce PROTEIN ISOFORMS in which one part of the isoforms is common while the other parts are different.
Alternate Splicing definition: Alternate Splicing is a process in which multiple protein isoforms or products are generated from a single gene as a result of splicing together different nonconsecutive exons during the processing of initially identical nascent transcripts of a gene into mature mRNA transcripts. An exon may be connected to any one of several alternative exons to form the mRNA and generate related proteins, often in a tissue or developmental stage specific manner.
Genetic Engineering definition: Directed modification of the gene complement of a living organism by such techniques as altering the DNA, substituting genetic material by means of a virus, transplanting whole nuclei, transplanting cell hybrids, etc.
Genetic Engineering definition: The technology of preparing recombinant DNA in vitro by cutting up DNA molecules and splicing together fragments from more than one organism.
RNA Splicing definition: The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.
RNA splicing definition: removal of introns from a primary transcript and the subsequent joining of exons in the production of a mature RNA molecule.
RNA splicing definition: The process of removing sections of the primary RNA transcript to remove sequences not present in the mature form of the RNA and joining the remaining sections to form the mature form of the RNA. [GOC:krc, GOC:mah]
pre-mRNA splicing factor activity definition: OBSOLETE. An activity involved in the removal of an intron from a pre-mRNA. [GOC:jl]
RNA Splicing definition: Removal of introns from mRNA precursors and the reattachment or annealing of exons.
mRNA splicing definition: OBSOLETE. The process in which excision of introns from the primary transcript of messenger RNA (mRNA) is followed by ligation of the two exon termini exposed by removal of each intron, so that mRNA consisting only of the joined exons is produced. [GOC:krc, ISBN:0198506732 "Oxford Dictionary of Biochemistry and Molecular Biology"]
Polypyrimidine Tract-Binding Protein definition: A RNA-binding protein that binds to polypyriminidine rich regions in the INTRONS of messenger RNAs. Polypyrimidine tract-binding protein may be involved in regulating the ALTERNATIVE SPLICING of mRNAs since its presence on an intronic RNA region that is upstream of an EXON inhibits the splicing of the exon into the final mRNA product.
Small Nuclear Ribonucleoprotein-Associated Protein N definition: Small Nuclear Ribonucleoprotein-Associated Protein N (240 aa, 25 kDa) is a nucleotide metabolism protein that is encoded by the human SNRPN gene and plays a role in mRNA splicing.
Splicing Factor Proline-and Glutamine-Rich definition: Splicing factor, proline- and glutamine-rich protein (707 aa, ~76 kDa) is encoded by the human SFPQ gene. This protein may be involved in messenger RNA processing, transcriptional regulation and the modulation of DNA secondary structure.
Protein Splicing definition: The excision of in-frame internal protein sequences (INTEINS) of a precursor protein, coupled with ligation of the flanking sequences (EXTEINS). Protein splicing is an autocatalytic reaction and results in the production of two proteins from a single primary translation product: the intein and the mature protein.
protein splicing definition: The post-translational removal of peptide sequences from within a protein sequence. [GOC:mah]
Protein Splicing definition: Excision of in-frame internal protein sequences (inteins) of a precursor protein, coupled with ligation of the flanking sequences (exteins). Protein splicing is an autocatalytic reaction and results in the production of two proteins from a single primary translation product: the intein and the mature protein.
Trans-Splicing definition: The joining of RNA from two different genes. One type of trans-splicing is the "spliced leader" type (primarily found in protozoans such as trypanosomes and in lower invertebrates such as nematodes) which results in the addition of a capped, noncoding, spliced leader sequence to the 5' end of mRNAs. Another type of trans-splicing is the "discontinuous group II introns" type (found in plant/algal chloroplasts and plant mitochondria) which results in the joining of two independently transcribed coding sequences. Both are mechanistically similar to conventional nuclear pre-mRNA cis-splicing. Mammalian cells are also capable of trans-splicing.
RNA, Ribosomal, Self-Splicing definition: Components of ribosomal RNA that undergo auto-catalyzed molecular rearrangements of their RNA sequence.
Group II intron splicing definition: The splicing of Group II introns. This occurs by a ribozymic mechanism where the intron sequence forms a distinct 3D structure, characteristic of Group II introns and containing splice site consensus sequences, that is involved in catalyzing the splicing reactions, though protein factors are also required in vivo. Splicing occurs by a series of two transesterification reactions (mechanistically similar to those for splicing of nuclear mRNAs) initiated by a bulged adenosine residue within the intron sequence as the initiating nucleophile. The intron is excised as a lariat. [GOC:krc, PMID:11377794]
Group III intron splicing definition: The splicing of Group III introns. This occurs by a ribozymic mechanism where the intron sequence forms a distinct 3D structure, characteristic of Group III introns, that is involved in catalyzing the splicing reactions, though protein factors are also required in vivo. Splicing occurs by a series of two transesterification reactions begun by a bulged adenosine residue within the intron sequence as the initiating nucleophile. The intron is excised as a lariat. Though very similar in structure and mechanism to Group II introns, Group III introns are smaller and more streamlined and the splice site consensus sequences are not as well conserved. [GOC:krc, PMID:11377794]
Group I intron splicing definition: The splicing of Group I introns. This occurs by a ribozymic mechanism where the intron sequence forms a distinct 3D structure, characteristic of Group I introns and involved in determining the locations of the splice sites (there do not appear to be consensus splice site sequences) as well as having a role in catalyzing the splicing reactions, though protein factors are also required in vivo. Splicing occurs by a series of two transesterification reactions, generally with exogenous guanosine as the initiating nucleophile. The intron is excised as a linear piece (though it may subsequently circularize). [GOC:krc, PMID:11377794]
SFPQ Gene definition: This gene may be involved in both transcriptional regulation and nuclear RNA processing.
SNRPN Gene definition: This gene plays a role in splicing of mRNA.
Splicing Regulation Pathway definition: While transcriptional regulation is often viewed as the most prevalent way extracellular signals act to regulate gene expression, post-transcriptional regulation of splicing, RNA stability, and translation are also regulated by extracellular signals. Sam68, a member of a family of RNA-binding proteins called STAR proteins, mediates alternative splicing in response to extracellular signals, such as altered splicing of CD44 in response to phorbol ester treatment of T cells. RNA binding and activity of SAM68 is regulated by upstream signals through phosphorylation and modulating of its interaction with other proteins, itself, and with RNA. Phorbol ester treatment of T cells stimulates the ras/ Map kinase pathway, activating Erk and phosphorylation of Sam68, inducing alternative splicing of CD44 and perhaps other cellular RNA targets. Sam68 is localized in the nucleus to a specific substructure called the Sam68/SLM Nuclear Bodies, colocalizing with splicing factors and helping to link signal transduction with RNA processing. Sam68 has been suggested to play a role in a variety of pathways, including insulin signaling and HIV gene expression, substituting for the activity of viral Rev protein, and being regulated by arginine methylation as well as phosphorylation. In addition to the role of Sam68 regulating posttranscriptional gene expression, Sam68 also interacts with transcription factors such as CBP and appears to regulate gene expression. Sam68 also appears to play a role in cell cycle progression through influencing RNA processing. During mitosis SAM68 is tyrosine phosphorylated and associated with Src. The interaction of Sam68 with RNA is repressed by this phosphorylation, whereas interaction of Sam68 with Ras-GAP is stimulated by phosphorylation. Sam68 appears to be downregulated in tumors and transformed cells and its expression is reduced during mitosis, suggesting it inhibits proliferation. The RNA binding domain in Sam68, called a KH domain, is absent in a splice isoform that is expressed in cells that display contact inhibition of cellular growth. Sam68 with the KH domain appears in some settings to stimulate the G1/S transition, while blocking mitosis in some reports. (BioCarta)
Tissue-Specific Splicing definition: Alternate splicing which is specific and typical for a given tissue.
intein-mediated protein splicing definition: The removal of an internal amino acid sequence (an intein) from a protein during protein maturation; the excision of inteins is precise and the N- and C-terminal exteins are joined by a normal peptide bond. Protein splicing involves 4 nucleophilic displacements by the 3 conserved splice junction residues. [GOC:ma, http://www.neb.com/neb/inteins.html]
regulation of RNA splicing definition: Any process that modulates the frequency, rate or extent of RNA splicing, the process of removing sections of the primary RNA transcript to remove sequences not present in the mature form of the RNA and joining the remaining sections to form the mature form of the RNA. [GOC:jl]
Protein Splicing Abnormality definition: A change in the amino acid sequence of a wild-type protein, resulting from aberrant excision of in-frame protein sequences (inteins) from a precursor protein followed by ligation of the flanking sequences (exteins).
nuclear speck definition: A discrete extra-nucleolar subnuclear domain, 20-50 in number, in which splicing factors are seen to be localized by immunofluorescence microscopy. [http://www.cellnucleus.com/]
alternate splicing of immunoglobulin genes definition: The generation of alternate transcripts of immunoglobulin genes through alternate splicing of exons. [ISBN:0781735149 "Fundamental Immunology", PMID:9185563]
negative regulation of RNA splicing definition: Any process that stops, prevents or reduces the frequency, rate or extent of RNA splicing. [GOC:mah]
positive regulation of RNA splicing definition: Any process that activates or increases the frequency, rate or extent of RNA splicing. [GOC:mah]
snoRNA splicing definition: The process of removing sections of a primary snoRNA transcript to remove sequences not present in the mature form of the snoRNA and joining the remaining sections to form the mature form of the snoRNA. [GOC:mah]
 
 
frFrench
épissage definition: Processus englobant l'excision des introns et la réunion des exons dans l'ARN.