Reactome | Formation of the Spliceosomal C complex containing intron lariat

Formation of the Spliceosomal C complex containing intron lariat

Stable Identifier

R-HSA-9794542

Type

Reaction [omitted]

Species

Homo sapiens

Compartment

nucleoplasm

Synonyms

First catalytic step of mRNA splicing

ReviewStatus

5/5

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Formation of the Spliceosomal C complex containing intron lariat

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The Spliceosomal B* complex and Spliceosomal C complex differ only in the structure of the pre-mRNA. Two magnesium ions coordinated by the U6 snRNA catalyze a transesterification reaction, the first reaction of splicing, converting the Spliceosomal B* complex into the Spliceosomal C complex by cleaving the 5' exon from the pre-mRNA and forming the intron lariat structure via a 5'-2' bond between the phosphate of the 5' residue of the intron and the 2' hydroxyl group of the adenosine residue of the intron branch point. The components of the Spliceosomal C complex have been ascertained using proteomic and structural methods (Jurica et al. 2002, Makarov et al. 2002, Rappsilber et al. 2002, Reichert et al. 2002, Bessonov et al. 2010, Agafonov et al. 2011, Schmidt et al. 2014, Zhan et al. 2018, Kastner et al. 2019).

Literature References

PubMed ID	Title	Journal	Year
20980672	Characterization of purified human Bact spliceosomal complexes reveals compositional and morphological changes during spliceosome activation and first step catalysis Sander, B, Will, CL, Lührmann, R, Anokhina, M, Golas, MM, Krasauskas, A, Bessonov, S, Stark, H, Urlaub, H	RNA	2010
12411573	Small nuclear ribonucleoprotein remodeling during catalytic activation of the spliceosome Makarova, OV, Will, CL, Gentzel, M, Lührmann, R, Wilm, M, Makarov, EM, Urlaub, H	Science	2002
24448447	Mass spectrometry-based relative quantification of proteins in precatalytic and catalytically active spliceosomes by metabolic labeling (SILAC), chemical labeling (iTRAQ), and label-free spectral count Lührmann, R, Deckert, J, Schmidt, C, Bessonov, S, Urlaub, H, Conrad, T, Grønborg, M	RNA	2014
30765414	Structural Insights into Nuclear pre-mRNA Splicing in Higher Eukaryotes Will, CL, Lührmann, R, Stark, H, Kastner, B	Cold Spring Harb Perspect Biol	2019
21536652	Semiquantitative proteomic analysis of the human spliceosome via a novel two-dimensional gel electrophoresis method Will, CL, Lührmann, R, Deckert, J, Odenwälder, P, Agafonov, DE, Bessonov, S, Urlaub, H, Wolf, E	Mol Cell Biol	2011
12414731	5' exon interactions within the human spliceosome establish a framework for exon junction complex structure and assembly Moore, MJ, Reichert, VL, Jurica, MS, Le, Hir H	Genes Dev	2002
11991638	Purification and characterization of native spliceosomes suitable for three-dimensional structural analysis. Grigorieff, N, Moore, MJ, Licklider, LJ, Gygi, SR, Jurica, MS	RNA	2002
12176931	Large-scale proteomic analysis of the human spliceosome. Lamond, AI, Mann, M, Rappsilber, J, Ryder, U	Genome Res	2002
29301961	Structure of a human catalytic step I spliceosome Yan, C, Shi, Y, Zhang, X, Lei, J, Zhan, X	Science	2018