Large ribonucleoprotein complex that assembles on a pre-mRNA and carries out RNA splicing. (Figures 11-18 and 11-19) ...
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Catalyzes the splicing of precursor message RNA. Major components are snRNPs (U1, U2, U4, U5 and U6).
A spliceosome is a complex of RNA and many protein subunits, that remove the non-coding introns from unprocessed mRNA. The mRNA of prokaryotes is simpler, and they do not have introns, so only eukaryotes have spliceosomes.
Spliceosomes remove introns and splice the exons of most nuclear genes. They are composed of 5 kinds of small nuclear RNA (snRNA) molecules and a large number of protein molecules. It is the snRNA — not the protein — that catalyzes the splicing reactions.
A complex assembly that interacts with the ends of an RNA intron in splicing RNA; releases an intron and joins two adjacent exons.
splitting evolution ...
~s: Organelles in which the splicing and excision reactions that remove introns from precursor messenger RNA molecules occur.
~ - The large, multi-component protein complex that mediates the splicing reaction of primary RNA transcripts.
~s that stimulate synthesis of intron-containing hnRNAs
enhancers that can stimulate specific promoters ...
~s consist of a variety of proteins and several small nuclear ribonucleoproteins (snRNPs) that recognize the splice sites.
snRNPs are located in the cell nucleus and are composed of RNA and protein molecules.
The removal of introns and splicing of exons is done with the ~. This is a complex of several snRNA molecules and some 145 different proteins.
The introns in most pre-mRNAs begin with a GU and end with an AG. Presumably these short sequences assist in guiding the ~.
Le Hir H, Izaurralde E, Maquat LE, Moore MJ: The ~ deposits multiple proteins 20-24 nucleotides upstream of mRNA exon-exon junctions. ...
and C/D-family RNAs have been discovered in Archaea (where they are dubbed sRNAs, as Archaea lack nucleoli), and likewise modify rRNA, and in the Cajal body of the eukaryote cell (small Cajal body scaRNPs), where they modify small nuclear RNAs (snRNAs), the RNA constituents of the ~ .
Introns are spliced out of pre-mRNA by ~s, which contain several small nuclear RNAs (snRNA), or the introns can be ribozymes that are spliced by themselves. RNA can also be altered by having its nucleotides modified to other nucleotides than A, C, G and U.
~ (← links)
Northern blot (← links)
Northern blot analysis (← links)
Hiv-1 reverse transcriptase (← links)
Molecular genetics (← links)
Human t-lymphotropic virus (← links)
Hybridization (← links)
In situ hybridization (← links) ...
See also: What is the meaning of Protein, RNA, Trans, Sequence, Proteins?