Page last updated: 2024-10-24
spliceosomal tri-snRNP complex assembly
Definition
Target type: biologicalprocess
The formation of a tri-snRNP complex containing U4 and U6 (or U4atac and U6atac) snRNAs and U5 snRNAs and associated proteins. This includes reannealing of U4 and U6 (or U4atac and U6atac) snRNAs released from previous rounds of splicing to reform the U4/U6 snRNP (or U4atac/U6atac snRNP) as well as the subsequent association of the U5 snRNP with the U4/U6 snRNP (or U4atac/U6atac snRNP) to form a tri-snRNP that is ready to reassemble into another spliceosome complex. [ISBN:0879695897, PMID:9452384]
The spliceosomal tri-snRNP complex assembly is a crucial step in pre-mRNA splicing, a process that removes introns and joins exons to produce mature mRNA. This complex is formed by the association of three small nuclear ribonucleoproteins (snRNPs): U1, U2, and U4/U6. Here's a detailed description of its assembly:
1. **U1 snRNP Recognition:** The process begins with U1 snRNP, which recognizes and binds to the 5' splice site (5'SS) of the pre-mRNA. The U1 snRNP's 5' end contains a small nuclear RNA (snRNA) molecule that base-pairs with the 5'SS sequence.
2. **U2 snRNP Recruitment:** Next, the U2 snRNP is recruited to the branch point sequence (BPS) located within the intron. The U2 snRNA within the U2 snRNP interacts with the BPS and the adjacent adenosine nucleotide, which will become the branch point for lariat formation.
3. **U4/U6 snRNP Binding:** The U4/U6 snRNP, which consists of two snRNAs associated with several proteins, is then brought into the complex. The U4 snRNA initially masks the active site of the U6 snRNA, which will play a key role in catalysis.
4. **Tri-snRNP Complex Formation:** These three snRNPs, along with several other proteins, assemble to form the tri-snRNP complex. This complex is highly dynamic and undergoes rearrangements as splicing progresses.
5. **U1 snRNP Displacement:** Following the formation of the tri-snRNP complex, U1 snRNP is displaced from the 5'SS. This event is facilitated by the interaction between U2 and U6 snRNAs.
6. **U4 snRNA Release:** The U4 snRNA is subsequently released from the complex, allowing the U6 snRNA to activate its catalytic site.
7. **Splicing Catalysis:** With the U6 snRNA active, the splicing reaction can proceed. The U6 snRNA interacts with the 5'SS and the BPS, triggering two transesterification reactions. These reactions lead to the removal of the intron as a lariat structure and the ligation of the exons, forming the mature mRNA.
The formation of the spliceosomal tri-snRNP complex is a tightly regulated process, involving numerous protein and RNA interactions. This assembly ensures the accurate recognition of splice sites and the efficient and precise removal of introns from pre-mRNA, ultimately leading to the production of functional proteins.'"
Proteins (2)
| Protein | Definition | Taxonomy |
|---|---|---|
| Serine/threonine-protein kinase PRP4 homolog | A serine/threonine-protein kinase PRP4 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q13523] | Homo sapiens (human) |
| Ubiquitin carboxyl-terminal hydrolase 4 | A ubiquitin carboxyl-terminal hydrolase 4 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q13107] | Homo sapiens (human) |
Compounds (70)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| imatinib | aromatic amine; benzamides; N-methylpiperazine; pyridines; pyrimidines | antineoplastic agent; apoptosis inducer; tyrosine kinase inhibitor | |
| staurosporine | indolocarbazole alkaloid; organic heterooctacyclic compound | apoptosis inducer; bacterial metabolite; EC 2.7.11.13 (protein kinase C) inhibitor; geroprotector | |
| gefitinib | aromatic ether; monochlorobenzenes; monofluorobenzenes; morpholines; quinazolines; secondary amino compound; tertiary amino compound | antineoplastic agent; epidermal growth factor receptor antagonist | |
| lestaurtinib | indolocarbazole | ||
| vatalanib | monochlorobenzenes; phthalazines; pyridines; secondary amino compound | angiogenesis inhibitor; antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor; vascular endothelial growth factor receptor antagonist | |
| ruboxistaurin | ruboxistaurin: inhibits protein kinase C beta; structure in first source | ||
| canertinib | monochlorobenzenes; morpholines; organofluorine compound; quinazolines | antineoplastic agent; tyrosine kinase inhibitor | |
| birb 796 | aromatic ether; morpholines; naphthalenes; pyrazoles; ureas | EC 2.7.11.24 (mitogen-activated protein kinase) inhibitor; immunomodulator | |
| sb 203580 | imidazoles; monofluorobenzenes; pyridines; sulfoxide | EC 2.7.11.1 (non-specific serine/threonine protein kinase) inhibitor; EC 2.7.11.24 (mitogen-activated protein kinase) inhibitor; geroprotector; Hsp90 inhibitor; neuroprotective agent | |
| enzastaurin | indoles; maleimides | ||
| erlotinib | aromatic ether; quinazolines; secondary amino compound; terminal acetylenic compound | antineoplastic agent; epidermal growth factor receptor antagonist; protein kinase inhibitor | |
| lapatinib | furans; organochlorine compound; organofluorine compound; quinazolines | antineoplastic agent; tyrosine kinase inhibitor | |
| sorafenib | (trifluoromethyl)benzenes; aromatic ether; monochlorobenzenes; phenylureas; pyridinecarboxamide | angiogenesis inhibitor; anticoronaviral agent; antineoplastic agent; EC 2.7.11.1 (non-specific serine/threonine protein kinase) inhibitor; ferroptosis inducer; tyrosine kinase inhibitor | |
| pd 173955 | PD 173955: inhibits src family-selective tyrosine kinase; structure in first source | aryl sulfide; dichlorobenzene; methyl sulfide; pyridopyrimidine | tyrosine kinase inhibitor |
| s 1033 | (trifluoromethyl)benzenes; imidazoles; pyridines; pyrimidines; secondary amino compound; secondary carboxamide | anticoronaviral agent; antineoplastic agent; tyrosine kinase inhibitor | |
| bms 387032 | N-(5-(((5-(1,1-dimethylethyl)-2-oxazolyl)methyl)thio)-2-thiazolyl)-4-piperidinecarboxamide: a CDK2 inhibitor with antineoplastic activity; structure in first source N-(5-{[(5-tert-butyl-1,3-oxazol-2-yl)methyl]sulfanyl}-1,3-thiazol-2-yl)piperidine-4-carboxamide : A secondary carboxamide resulting from the formal condensation of the carboxy group of piperidine-4-carboxylic acid with the amino group of 5-{[(5-tert-butyl-1,3-oxazol-2-yl)methyl]sulfanyl}-1,3-thiazol-2-amine. It is an ATP-competitive inhibitor of CDK2, CDK7 and CDK9 kinases and exhibits anti-cancer properties. | 1,3-oxazoles; 1,3-thiazoles; organic sulfide; piperidinecarboxamide; secondary carboxamide | angiogenesis inhibitor; antineoplastic agent; apoptosis inducer; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| tandutinib | aromatic ether; N-arylpiperazine; N-carbamoylpiperazine; phenylureas; piperidines; quinazolines; tertiary amino compound | antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor | |
| vx-745 | aryl sulfide; dichlorobenzene; difluorobenzene; pyrimidopyridazine | anti-inflammatory drug; apoptosis inducer; EC 2.7.11.24 (mitogen-activated protein kinase) inhibitor | |
| dasatinib | dasatinib (anhydrous) : An aminopyrimidine that is 2-methylpyrimidine which is substituted at position 4 by the primary amino group of 2-amino-1,3-thiazole-5-carboxylic acid and at position 6 by a 4-(2-hydroxyethyl)piperazin-1-yl group, and in which the carboxylic acid group has been formally condensed with 2-chloro-6-methylaniline to afford the corresponding amide. A multi-targeted kinase inhibitor, it is used, particularly as the monohydrate, for the treatment of chronic, accelerated, or myeloid or lymphoid blast phase chronic myeloid leukemia. Note that the name 'dasatinib' is used to refer to the monohydrate (USAN) as well as to anhydrous dasatinib (INN). N-(2-chloro-6-methylphenyl)-2-((6-(4-(2-hydroxyethyl)piperazin-1-yl)-2-methylpyrimidin-4-yl)amino)-1,3-thiazole-5-carboxamide: a dasatinib prodrug; structure in first source | 1,3-thiazoles; aminopyrimidine; monocarboxylic acid amide; N-(2-hydroxyethyl)piperazine; N-arylpiperazine; organochlorine compound; secondary amino compound; tertiary amino compound | anticoronaviral agent; antineoplastic agent; tyrosine kinase inhibitor |
| zd 6474 | CH 331: structure in first source | aromatic ether; organobromine compound; organofluorine compound; piperidines; quinazolines; secondary amine | antineoplastic agent; tyrosine kinase inhibitor |
| alvocidib | alvocidib : A synthetic dihydroxyflavone that is 5,7-dihydroxyflavone which is substituted by a 3-hydroxy-1-methylpiperidin-4-yl group at position 8 and by a chlorine at the 2' position (the (-)-3S,4R stereoisomer). A cyclin-dependent kinase 9 (CDK9) inhibitor, it has been studied for the treatment of acute myeloid leukaemia, arthritis and atherosclerotic plaque formation. alvocidib: structure given in first source | dihydroxyflavone; hydroxypiperidine; monochlorobenzenes; tertiary amino compound | antineoplastic agent; antirheumatic drug; apoptosis inducer; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| bosutinib | 4-((2,4-dichloro-5-methoxyphenyl)amino)-6-methoxy-7-(3-(4-methyl-1-piperazinyl)propoxy)-3-quinolinecarbonitrile: a Src kinase inhibitor; structure in first source | aminoquinoline; aromatic ether; dichlorobenzene; N-methylpiperazine; nitrile; tertiary amino compound | antineoplastic agent; tyrosine kinase inhibitor |
| su 11248 | monocarboxylic acid amide; pyrroles | angiogenesis inhibitor; antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor; immunomodulator; neuroprotective agent; vascular endothelial growth factor receptor antagonist | |
| vx680 | N-arylpiperazine | ||
| axitinib | aryl sulfide; benzamides; indazoles; pyridines | antineoplastic agent; tyrosine kinase inhibitor; vascular endothelial growth factor receptor antagonist | |
| pd 184352 | 2-(2-chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluorobenzamide: inhibits MAP kinase kinase; structure in first source | aminobenzoic acid | |
| bms345541 | 4(2'-aminoethyl)amino-1,8-dimethylimidazo(1,2-a)quinoxaline: structure in first source | quinoxaline derivative | |
| midostaurin | midostaurin : An organic heterooctacyclic compound that is the N-benzoyl derivative of staurosporine. | benzamides; gamma-lactam; indolocarbazole; organic heterooctacyclic compound | antineoplastic agent; EC 2.7.11.13 (protein kinase C) inhibitor |
| ki 20227 | |||
| pi103 | PI103: pyridofuropyrimidine antineoplastic; a potent inhibitor of class I phosphatidylinositide 3-kinases (PI3K); structure in first soruce | aromatic amine; morpholines; organic heterotricyclic compound; phenols; tertiary amino compound | antineoplastic agent; EC 2.7.1.137 (phosphatidylinositol 3-kinase) inhibitor; mTOR inhibitor |
| hki 272 | nitrile; quinolines | antineoplastic agent; tyrosine kinase inhibitor | |
| tofacitinib | tofacitinib : A pyrrolopyrimidine that is pyrrolo[2,3-d]pyrimidine substituted at position 4 by an N-methyl,N-(1-cyanoacetyl-4-methylpiperidin-3-yl)amino moiety. Used as its citrate salt to treat moderately to severely active rheumatoid arthritis. | N-acylpiperidine; nitrile; pyrrolopyrimidine; tertiary amino compound | antirheumatic drug; EC 2.7.10.2 (non-specific protein-tyrosine kinase) inhibitor |
| n-(6-chloro-7-methoxy-9h-beta-carbolin-8-yl)-2-methylnicotinamide | |||
| cediranib | aromatic ether | ||
| masitinib | 1,3-thiazoles; benzamides; N-alkylpiperazine; pyridines | antineoplastic agent; antirheumatic drug; tyrosine kinase inhibitor | |
| pazopanib | pazopanib : A pyrimidine that is 5-(pyrimidin-2-yl}amino-2-methylbenzenesulfonamide substituted at position 4 by a (2,3-dimethylindazol-6-yl)(methyl)amino group. Used as its hydrochloride salt for treatment of kidney cancer. pazopanib: a protein kinase inhibitor | aminopyrimidine; indazoles; sulfonamide | angiogenesis modulating agent; antineoplastic agent; tyrosine kinase inhibitor; vascular endothelial growth factor receptor antagonist |
| azd 6244 | AZD 6244: a MEK inhibitor | benzimidazoles; bromobenzenes; hydroxamic acid ester; monochlorobenzenes; organofluorine compound; secondary amino compound | anticoronaviral agent; antineoplastic agent; EC 2.7.11.24 (mitogen-activated protein kinase) inhibitor |
| su 14813 | 5-((5-fluoro-2-oxo-1,2-dihydro-3H-indol-3-ylidene)methyl)-N-(2-hydroxy-3-morpholin-4-ylpropyl)-2,4-dimethyl-1H-pyrrole-3-carboxamide: has both antineoplastic and antiangiogenic activities; structure in first source | ||
| bibw 2992 | aromatic ether; enamide; furans; monochlorobenzenes; organofluorine compound; quinazolines; secondary carboxamide; tertiary amino compound | antineoplastic agent; tyrosine kinase inhibitor | |
| tg100-115 | 3,3'-(2,4-diaminopteridine-6,7-diyl)diphenol: for treatment of ischemia reperfusion injury; structure in first source | pteridines | |
| pha 665752 | dichlorobenzene; enamide; indolones; N-acylpyrrolidine; pyrrolecarboxamide; secondary carboxamide; sulfone; tertiary carboxamide | antineoplastic agent; c-Met tyrosine kinase inhibitor | |
| 6-[[5-fluoro-2-(3,4,5-trimethoxyanilino)-4-pyrimidinyl]amino]-2,2-dimethyl-4H-pyrido[3,2-b][1,4]oxazin-3-one | methoxybenzenes; substituted aniline | ||
| brivanib | aromatic ether; diether; fluoroindole; pyrrolotriazine; secondary alcohol | angiogenesis inhibitor; antineoplastic agent; apoptosis inducer; drug metabolite; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor; fibroblast growth factor receptor antagonist | |
| at 7519 | 4-(2,6-dichlorobenzamido)-N-(piperidin-4-yl)-pyrazole-3-carboxamide : A member of the class of pryrazoles that is 4-amino-1H-pyrazole-3-carboxylic acid in which the primary amino group has been acylated by a 2,6-dichlorobenzoyl group and in which the carboxylic acid has been converted into a carboxamide by formal condensation with the primary amino group of 4-aminopiperidine. | dichlorobenzene; piperidines; pyrazoles; secondary carboxamide | antineoplastic agent; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| bi 2536 | |||
| nvp-ast487 | NVP-AST487: antineoplastic; a RET kinase inhibitor that blocks growth and calcitonin gene expression through distinct mechanisms in medullary thyroid cancer cells | ||
| kw 2449 | KW 2449: has both multikinase inhibitory activity and antineoplastic activity; structure in first source | ||
| abt 869 | aromatic amine; indazoles; phenylureas | angiogenesis inhibitor; antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor | |
| vialinin a | vialinin A: free radical scavenger from an edible mushroom in China; structure in first source | ||
| gw 2580 | 5-(3-methoxy-4-((4-methoxybenzyl)oxy)benzyl)pyrimidine-2,4-diamine: a cFMS kinase inhibitor; structure in first source | ||
| crizotinib | crizotinib : A 3-[1-(2,6-dichloro-3-fluorophenyl)ethoxy]-5-[1-(piperidin-4-yl)pyrazol-4-yl]pyridin-2-amine that has R configuration at the chiral centre. The active enantiomer, it acts as a kinase inhibitor and is used for the treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) Crizotinib: A piperidine and aminopyridine derivative that acts as an inhibitor of RECEPTOR PROTEIN-TYROSINE KINASES, including ANAPLASTIC LYMPHOMA KINASE (ALK) and HEPATOCYTE GROWTH FACTOR RECEPTOR (HGFR; c-Met). It is used in the treatment of NON-SMALL CELL LUNG CANCER. | 3-[1-(2,6-dichloro-3-fluorophenyl)ethoxy]-5-[1-(piperidin-4-yl)pyrazol-4-yl]pyridin-2-amine | antineoplastic agent; biomarker; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor |
| chir-265 | aromatic ether | ||
| motesanib | pyridinecarboxamide | ||
| mln8054 | benzazepine | ||
| GDC-0879 | indanes; ketoxime; primary alcohol; pyrazoles; pyridines | antineoplastic agent; B-Raf inhibitor | |
| gsk 461364 | GSK 461364: an antineoplastic agent that inhibits polo-like kinase 1 | (trifluoromethyl)benzenes | |
| azd 1152-hqpa | AZD2811: has antineoplastic activity; structure in first source | anilide; monofluorobenzenes; primary alcohol; pyrazoles; quinazolines; secondary amino compound; secondary carboxamide; tertiary amino compound | antineoplastic agent; Aurora kinase inhibitor |
| nvp-tae684 | piperidines | ||
| fedratinib | fedratinib: a selective small-molecule inhibitor of JAK2 | sulfonamide | |
| gsk690693 | 1,2,5-oxadiazole; acetylenic compound; aromatic amine; aromatic ether; imidazopyridine; piperidines; primary amino compound; tertiary alcohol | antineoplastic agent; EC 2.7.11.1 (non-specific serine/threonine protein kinase) inhibitor | |
| gdc 0941 | pictrelisib : A sulfonamide composed of indazole, morpholine, and methylsulfonyl-substituted piperazine rings bound to a thienopyrimidine ring. | indazoles; morpholines; piperazines; sulfonamide; thienopyrimidine | EC 2.7.1.137 (phosphatidylinositol 3-kinase) inhibitor |
| plx 4720 | PLX 4720: a B-Raf(V600E) kinase inhibitor; structure in first source | aromatic ketone; difluorobenzene; organochlorine compound; pyrrolopyridine; sulfonamide | antineoplastic agent; B-Raf inhibitor |
| sgx 523 | aryl sulfide; biaryl; pyrazoles; quinolines; triazolopyridazine | c-Met tyrosine kinase inhibitor; nephrotoxic agent | |
| quizartinib | benzoimidazothiazole; isoxazoles; morpholines; phenylureas | antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor; necroptosis inhibitor | |
| incb-018424 | nitrile; pyrazoles; pyrrolopyrimidine | antineoplastic agent; EC 2.7.10.2 (non-specific protein-tyrosine kinase) inhibitor | |
| gsk 1838705a | organonitrogen compound; organooxygen compound | ||
| gsk 1363089 | GSK 1363089: a multikinase inhibitor that acts on Met, RON, Axl, and VEGFR; structure in first source | aromatic ether | |
| chir 258 | |||
| nintedanib | nintedanib : A member of the class of oxindoles that is a kinase inhibitor used (in the form of its ethylsulfonate salt) for the treatment of idiopathic pulmonary fibrosis and cancer. | ||
| pp242 | torkinib : A member of the class of pyrazolopyrimidines that is 1H-pyrazolo[3,4-d]pyrimidine substituted by isopropyl, 5-hydroxyindol-2-yl and amino groups at positions 1, 3 and 4 respectively. It is a potent inhibitor of mTOR and exhibits anti-cancer properties. | aromatic amine; biaryl; hydroxyindoles; phenols; primary amino compound; pyrazolopyrimidine | antineoplastic agent; mTOR inhibitor |