Familial dysautonomia is a debilitating congenital neurodegenerative disorder with no causative therapy. It is caused by a homozygous mutation in ELP1 gene, resulting in the production of the transcript lacking exon 20. The compounds studied as potential treatments include the clinical candidate kinetin, a plant hormone from the cytokinin family. We explored the relationship between the structure of a set of kinetin derivatives (N = 72) and their ability to correct aberrant splicing of the ELP1 gene. Active compounds can be obtained by the substitution of the purine ring with chlorine and fluorine at the C2 atom, with a small alkyl group at the N7 atom, or with diverse groups at the C8 atom. On the other hand, a substitution at the N3 or N9 atoms resulted in a loss of activity. We successfully tested a hypothesis inspired by the remarkable tolerance of the position C8 to substitution, postulating that the imidazole of the purine moiety is not required for the activity. We also evaluated the activity of phytohormones from other families, but none of them corrected ELP1 mRNA aberrant splicing. A panel of in vitro ADME assays, including evaluation of transport across model barriers, stability in plasma and in the presence of liver microsomal fraction as well as plasma protein binding, was used for an initial estimation of the potential bioavailability of the active compounds. Finally, a RNA-seq data suggest that 8-aminokinetin modulates expression spliceosome components.
- Klíčová slova
- ADME in vitro, Alternative splicing, Cytokinin, ELP1, Kinetin, mRNA metabolism,
- MeSH
- kinetin * farmakologie chemie MeSH
- lidé MeSH
- molekulární struktura MeSH
- prekurzory RNA * genetika metabolismus MeSH
- sestřih RNA * účinky léků MeSH
- transkripční elongační faktory metabolismus genetika MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- Elp1 protein, human MeSH Prohlížeč
- kinetin * MeSH
- prekurzory RNA * MeSH
- transkripční elongační faktory MeSH
Germline CHEK2 pathogenic variants confer an increased risk of female breast cancer (FBC). Here we describe a recurrent germline intronic variant c.1009-118_1009-87delinsC, which showed a splice acceptor shift in RNA analysis, introducing a premature stop codon (p.Tyr337PhefsTer37). The variant was found in 21/10,204 (0.21%) Czech FBC patients compared to 1/3250 (0.03%) controls (p = 0.04) and in 4/3639 (0.11%) FBC patients from an independent German dataset. In addition, we found this variant in 5/2966 (0.17%) Czech (but none of the 443 German) ovarian cancer patients, three of whom developed early-onset tumors. Based on these observations, we classified this variant as likely pathogenic.
- Klíčová slova
- Breast cancer, Deep intronic CHEK2 variant, Genetic testing, NGS, RNA analysis,
- MeSH
- checkpoint kinasa 2 * genetika MeSH
- dospělí MeSH
- genetická predispozice k nemoci * genetika MeSH
- introny * genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory prsu * genetika MeSH
- nádory vaječníků genetika MeSH
- prekurzory RNA genetika MeSH
- sestřih RNA * genetika MeSH
- zárodečné mutace * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Německo MeSH
- Názvy látek
- CHEK2 protein, human MeSH Prohlížeč
Giardia lambliacauses giardiasis, one of the most common human infectious diseases globally. Previous studies from our lab have shown that hsp90 gene ofGiardia is split into two halves, namely hspN and hspC. The independent pre-mRNAs of these split genes join by trans-splicing, producing a full-length Hsp90 (FlHsp90) mRNA. Genetic manipulation of the participating genes is necessary to understand the mechanism and significance of such trans-splicing based expression of Hsp90. In this study, we have performed transfection based exogenous expression of hspN and/or hspC in G. lamblia. We electroporated a plasmid containing the Avi-tagged hspN component of Hsp90 and examined its fate in G. lamblia. We show that the exogenously expressed hspN RNA gets trans-spliced to endogenously expressed hspC RNA, giving rise to a hybrid-FlHsp90. We highlight the importance of cis-elements in this trans-splicing reaction through mutational analysis. The episomal plasmid carrying deletions in the intronic region of hspN, showed inhibition of the trans-splicing reaction.Additionally, exogenous hspC RNA also followed the same fate as of exogenous hspN, while upon co-transfection with episomal hspN, they underwent trans-splicing with each other. Using eGFP as a test protein, we have shown that intronic sequences of hsp90 gene can guide trans-splicing mediated repair of any associated exonic sequences. Our study provides in vivo validation of Hsp90 trans-splicing, showing crucial role of cis-elements and importantly highlights the potential of hsp90 intronic sequences to function as a minimal splicing tool.
- Klíčová slova
- Gene expression, Giardia lamblia, Hsp90, RNA splicing, Transfection,
- MeSH
- Giardia lamblia * genetika MeSH
- introny genetika MeSH
- prekurzory RNA genetika MeSH
- proteiny tepelného šoku HSP90 * genetika MeSH
- protozoální proteiny * genetika MeSH
- trans-splicing * genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- prekurzory RNA MeSH
- proteiny tepelného šoku HSP90 * MeSH
- protozoální proteiny * MeSH
Spliceosomal snRNPs are multicomponent particles that undergo a complex maturation pathway. Human Sm-class snRNAs are generated as 3'-end extended precursors, which are exported to the cytoplasm and assembled together with Sm proteins into core RNPs by the SMN complex. Here, we provide evidence that these pre-snRNA substrates contain compact, evolutionarily conserved secondary structures that overlap with the Sm binding site. These structural motifs in pre-snRNAs are predicted to interfere with Sm core assembly. We model structural rearrangements that lead to an open pre-snRNA conformation compatible with Sm protein interaction. The predicted rearrangement pathway is conserved in Metazoa and requires an external factor that initiates snRNA remodeling. We show that the essential helicase Gemin3, which is a component of the SMN complex, is crucial for snRNA structural rearrangements during snRNP maturation. The SMN complex thus facilitates ATP-driven structural changes in snRNAs that expose the Sm site and enable Sm protein binding.
- MeSH
- HeLa buňky MeSH
- jádro snRNP - proteiny genetika MeSH
- lidé MeSH
- prekurzory RNA * metabolismus MeSH
- proteinový komplex SMN metabolismus MeSH
- ribonukleoproteiny malé jaderné metabolismus MeSH
- RNA malá jaderná * metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- jádro snRNP - proteiny MeSH
- prekurzory RNA * MeSH
- proteinový komplex SMN MeSH
- ribonukleoproteiny malé jaderné MeSH
- RNA malá jaderná * MeSH
A significant number of individuals with a rare disorder such as Usher syndrome (USH) and (non-)syndromic autosomal recessive retinitis pigmentosa (arRP) remain genetically unexplained. Therefore, we assessed subjects suspected of USH2A-associated disease and no or mono-allelic USH2A variants using whole genome sequencing (WGS) followed by an improved pipeline for variant interpretation to provide a conclusive diagnosis. One hundred subjects were screened using WGS to identify causative variants in USH2A or other USH/arRP-associated genes. In addition to the existing variant interpretation pipeline, a particular focus was put on assessing splice-affecting properties of variants, both in silico and in vitro. Also structural variants were extensively addressed. For variants resulting in pseudoexon inclusion, we designed and evaluated antisense oligonucleotides (AONs) using minigene splice assays and patient-derived photoreceptor precursor cells. Biallelic variants were identified in 49 of 100 subjects, including novel splice-affecting variants and structural variants, in USH2A or arRP/USH-associated genes. Thirteen variants were shown to affect USH2A pre-mRNA splicing, including four deep-intronic USH2A variants resulting in pseudoexon inclusion, which could be corrected upon AON treatment. We have shown that WGS, combined with a thorough variant interpretation pipeline focused on assessing pre-mRNA splicing defects and structural variants, is a powerful method to provide subjects with a rare genetic condition, a (likely) conclusive genetic diagnosis. This is essential for the development of future personalized treatments and for patients to be eligible for such treatments.
- Klíčová slova
- USH2A, Usher syndrome, antisense oligonucleotides, minigene splice assay, photoreceptor precursor cells, pseudoexon, retinitis pigmentosa, splicing, usherin, whole genome sequencing,
- MeSH
- extracelulární matrix - proteiny genetika MeSH
- lidé MeSH
- mutace MeSH
- prekurzory RNA MeSH
- retinopathia pigmentosa * diagnóza MeSH
- rodokmen MeSH
- sekvenování celého genomu MeSH
- Usherovy syndromy * diagnóza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- extracelulární matrix - proteiny MeSH
- prekurzory RNA MeSH
- USH2A protein, human MeSH Prohlížeč
The coordination of cell division with stress response is essential for maintaining genome stability in plant meristems. Proteins involved in pre-mRNA splicing are important for these processes in animal and human cells. Based on its homology to the splicing factor SART1, which is implicated in the control of cell division and genome stability in human cells, we analyzed if MDF has similar functions in plants. We found that MDF associates with U4/U6.U5 tri-snRNP proteins and is essential for correct splicing of 2,037 transcripts. Loss of MDF function leads to cell division defects and cell death in meristems and was associated with up-regulation of stress-induced genes and down-regulation of mitotic regulators. In addition, the mdf-1 mutant is hypersensitive to DNA damage treatment supporting its role in coordinating stress response with cell division. Our analysis of a dephosphomutant of MDF suggested how its protein activity might be controlled. Our work uncovers the conserved function of a plant splicing factor and provides novel insight into the interplay of pre-mRNA processing and genome stability in plants.
- MeSH
- Arabidopsis * genetika metabolismus MeSH
- buněčné dělení genetika MeSH
- lidé MeSH
- malý jaderný ribonukleoprotein U4-U6 genetika metabolismus MeSH
- malý jaderný ribonukleoprotein U5 * genetika metabolismus MeSH
- nestabilita genomu MeSH
- prekurzory RNA genetika metabolismus MeSH
- sestřihové faktory genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- AT5G16780 protein, Arabidopsis MeSH Prohlížeč
- malý jaderný ribonukleoprotein U4-U6 MeSH
- malý jaderný ribonukleoprotein U5 * MeSH
- milk-derived factor MeSH Prohlížeč
- prekurzory RNA MeSH
- sestřihové faktory MeSH
RNA splicing, the process of intron removal from pre-mRNA, is essential for the regulation of gene expression. It is controlled by the spliceosome, a megadalton RNA-protein complex that assembles de novo on each pre-mRNA intron through an ordered assembly of intermediate complexes1,2. Spliceosome activation is a major control step that requires substantial protein and RNA rearrangements leading to a catalytically active complex1-5. Splicing factor 3B subunit 1 (SF3B1) protein-a subunit of the U2 small nuclear ribonucleoprotein6-is phosphorylated during spliceosome activation7-10, but the kinase that is responsible has not been identified. Here we show that cyclin-dependent kinase 11 (CDK11) associates with SF3B1 and phosphorylates threonine residues at its N terminus during spliceosome activation. The phosphorylation is important for the association between SF3B1 and U5 and U6 snRNAs in the activated spliceosome, termed the Bact complex, and the phosphorylation can be blocked by OTS964, a potent and selective inhibitor of CDK11. Inhibition of CDK11 prevents spliceosomal transition from the precatalytic complex B to the activated complex Bact and leads to widespread intron retention and accumulation of non-functional spliceosomes on pre-mRNAs and chromatin. We demonstrate a central role of CDK11 in spliceosome assembly and splicing regulation and characterize OTS964 as a highly selective CDK11 inhibitor that suppresses spliceosome activation and splicing.
- MeSH
- aktivace enzymů účinky léků MeSH
- chinolony farmakologie MeSH
- chromatin metabolismus MeSH
- cyklin-dependentní kinasy * antagonisté a inhibitory metabolismus MeSH
- fosfoproteiny * chemie metabolismus MeSH
- fosforylace MeSH
- malý jaderný ribonukleoprotein U2 * chemie metabolismus MeSH
- prekurzory RNA * genetika metabolismus MeSH
- sestřih RNA * účinky léků MeSH
- spliceozomy * účinky léků metabolismus MeSH
- threonin metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chinolony MeSH
- chromatin MeSH
- cyklin-dependentní kinasy * MeSH
- fosfoproteiny * MeSH
- malý jaderný ribonukleoprotein U2 * MeSH
- OTS964 MeSH Prohlížeč
- prekurzory RNA * MeSH
- threonin MeSH
Ribosome biogenesis is an essential, energy demanding process whose deregulation has been implicated in cancer, aging, and neurodegeneration. Ribosome biogenesis is therefore under surveillance of pathways including the p53 tumor suppressor. Here, we first performed a high-content siRNA-based screen of 175 human ribosome biogenesis factors, searching for impact on p53. Knock-down of 4 and 35 of these proteins in U2OS cells reduced and increased p53 abundance, respectively, including p53 accumulation after depletion of BYSL, DDX56, and WDR75, the effects of which were validated in several models. Using complementary approaches including subcellular fractionation, we demonstrate that endogenous human WDR75 is a nucleolar protein and immunofluorescence analysis of ectopic GFP-tagged WDR75 shows relocation to nucleolar caps under chemically induced nucleolar stress, along with several canonical nucleolar proteins. Mechanistically, we show that WDR75 is required for pre-rRNA transcription, through supporting the maintenance of physiological levels of RPA194, a key subunit of the RNA polymerase I. Furthermore, WDR75 depletion activated the RPL5/RPL11-dependent p53 stabilization checkpoint, ultimately leading to impaired proliferation and cellular senescence. These findings reveal a crucial positive role of WDR75 in ribosome biogenesis and provide a resource of human ribosomal factors the malfunction of which affects p53.
- MeSH
- buněčné jadérko genetika metabolismus MeSH
- DEAD-box RNA-helikasy metabolismus MeSH
- jaderné proteiny genetika metabolismus MeSH
- lidé MeSH
- molekuly buněčné adheze metabolismus MeSH
- nádorové buněčné linie MeSH
- nádorový supresorový protein p53 genetika metabolismus MeSH
- prekurzory RNA metabolismus MeSH
- ribozomální proteiny * genetika metabolismus MeSH
- ribozomy genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- BYSL protein, human MeSH Prohlížeč
- DDX56 protein, human MeSH Prohlížeč
- DEAD-box RNA-helikasy MeSH
- jaderné proteiny MeSH
- molekuly buněčné adheze MeSH
- nádorový supresorový protein p53 MeSH
- prekurzory RNA MeSH
- ribozomální proteiny * MeSH
- TP53 protein, human MeSH Prohlížeč
Ca2+-insensitive and -sensitive E1 subunits of the 2-oxoglutarate dehydrogenase complex (OGDHC) regulate tissue-specific NADH and ATP supply by mutually exclusive OGDH exons 4a and 4b. Here we show that their splicing is enforced by distant lariat branch points (dBPs) located near the 5' splice site of the intervening intron. dBPs restrict the intron length and prevent transposon insertions, which can introduce or eliminate dBP competitors. The size restriction was imposed by a single dominant dBP in anamniotes that expanded into a conserved constellation of four dBP adenines in amniotes. The amniote clusters exhibit taxon-specific usage of individual dBPs, reflecting accessibility of their extended motifs within a stable RNA hairpin rather than U2 snRNA:dBP base-pairing. The dBP expansion took place in early terrestrial species and was followed by a uridine enrichment of large downstream polypyrimidine tracts in mammals. The dBP-protected megatracts permit reciprocal regulation of exon 4a and 4b by uridine-binding proteins, including TIA-1/TIAR and PUF60, which promote U1 and U2 snRNP recruitment to the 5' splice site and BP, respectively, but do not significantly alter the relative dBP usage. We further show that codons for residues critically contributing to protein binding sites for Ca2+ and other divalent metals confer the exon inclusion order that mirrors the Irving-Williams affinity series, linking the evolution of auxiliary splicing motifs in exons to metallome constraints. Finally, we hypothesize that the dBP-driven selection for Ca2+-dependent ATP provision by E1 facilitated evolution of endothermy by optimizing the aerobic scope in target tissues.
- MeSH
- alternativní sestřih * MeSH
- exony MeSH
- HEK293 buňky MeSH
- introny * MeSH
- ketoglutarátdehydrogenasový komplex genetika metabolismus MeSH
- lidé MeSH
- messenger RNA chemie metabolismus MeSH
- místa sestřihu RNA MeSH
- molekulární evoluce MeSH
- obratlovci genetika MeSH
- prekurzory RNA chemie metabolismus MeSH
- protein - isoformy genetika metabolismus MeSH
- rozptýlené repetitivní sekvence MeSH
- sestřihové faktory metabolismus MeSH
- spliceozomy metabolismus MeSH
- termoregulace genetika MeSH
- vápník metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- ketoglutarátdehydrogenasový komplex MeSH
- messenger RNA MeSH
- místa sestřihu RNA MeSH
- prekurzory RNA MeSH
- protein - isoformy MeSH
- sestřihové faktory MeSH
- vápník MeSH
Tick-borne encephalitis virus (TBEV), a member of the genus Flavivirus (Flaviviridae), is a causative agent of a severe neuroinfection. Recently, several flaviviruses have been shown to interact with host protein synthesis. In order to determine whether TBEV interacts with this host process in its natural target cells, we analysed de novo protein synthesis in a human cell line derived from cerebellar medulloblastoma (DAOY HTB-186). We observed a significant decrease in the rate of host protein synthesis, including the housekeeping genes HPRT1 and GAPDH and the known interferon-stimulated gene viperin. In addition, TBEV infection resulted in a specific decrease of RNA polymerase I (POLR1) transcripts, 18S and 28S rRNAs and their precursor, 45-47S pre-rRNA, but had no effect on the POLR3 transcribed 5S rRNA levels. To our knowledge, this is the first report of flavivirus-induced decrease of specifically POLR1 rRNA transcripts accompanied by host translational shut-off.
- MeSH
- genetická transkripce MeSH
- klíšťová encefalitida genetika metabolismus virologie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- prekurzory RNA MeSH
- proteosyntéza genetika MeSH
- RNA ribozomální genetika metabolismus MeSH
- RNA-polymerasa I genetika metabolismus MeSH
- viry klíšťové encefalitidy fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- prekurzory RNA MeSH
- RNA ribozomální MeSH
- RNA-polymerasa I MeSH