scholarly journals CRISPR editing of sftb-1/SF3B1 in C. elegans allows the identification of synthetic interactions with cancer-related mutations and the chemical inhibition of splicing

2019 ◽  
Author(s):  
Xènia Serrat ◽  
Dmytro Kukhtar ◽  
Eric Cornes ◽  
Anna Esteve-Codina ◽  
Helena Benlloch ◽  
...  
Keyword(s):  
Alternative Splicing ◽  
Synthetic Lethality ◽  
Splicing Factor ◽  
Homogeneous Population ◽  
Synthetic Lethal ◽  
C Elegans ◽  
U2 Snrnp ◽  
Pladienolide B ◽  
Cancer Mutations ◽  
Chemical Inhibition

ABSTRACTSF3B1 is the most frequently mutated splicing factor in cancer. Mutations in SF3B1 confer growth advantages to cancer cells but they may also confer vulnerabilities that can be therapeutically targeted. In contrast to other animal models, SF3B1 cancer mutations can be maintained in homozygosis in C. elegans, allowing synthetic lethal screens with a homogeneous population of animals. These mutations cause alternative splicing (AS) defects in C. elegans, as it occurs in SF3B1-mutated human cells. In a screen, we identified RNAi of U2 snRNP components that cause synthetic lethality with sftb-1/SF3B1 mutations. We also detected synthetic interactions between sftb-1 mutants and cancer-related mutations in uaf-2/U2AF1 or rsp-4/SRSF2, demonstrating that this model can identify interactions between mutations that are mutually exclusive in human tumors. Finally, we have edited an SFTB-1 domain to sensitize C. elegans to the splicing inhibitor pladienolide B. Thus, we have established a multicellular model for SF3B1 mutations amenable for high-throughput genetic and chemical screens.

scholarly journals Integration of pathway, cellular and genetic context reveals principles of synthetic lethality that affect reproducibility

2019 ◽  
Author(s):  
Angel A. Ku ◽  
Sameera Kongara ◽  
Hsien-Ming Hu ◽  
Xin Zhao ◽  
Di Wu ◽  
...  
Keyword(s):  
Genetic Interaction ◽  
Synthetic Lethality ◽  
Synthetic Lethal ◽  
Testing Framework ◽  
Gene Level ◽  
Cancer Mutations ◽  
Experimental Approaches ◽  
Interaction Map ◽  
Mutant Cells ◽  
Genetic Context

ABSTRACTSynthetic lethal screens have the potential to identify new vulnerabilities incurred by specific cancer mutations but have been hindered by lack of agreement between studies. Using KRAS as a model, we identified that published synthetic lethal screens significantly overlap at the pathway rather than gene level. Analysis of pathways encoded as protein networks identified synthetic lethal candidates that were more reproducible than those previously reported. Lack of overlap likely stems from biological rather than technical limitations as most synthetic lethal phenotypes were strongly modulated by changes in cellular conditions or genetic context, the latter determined using a pairwise genetic interaction map that identified numerous interactions that suppress synthetic lethal effects. Accounting for pathway, cellular and genetic context nominates a DNA repair dependency in KRAS-mutant cells, mediated by a network containing BRCA1. We provide evidence for why most reported synthetic lethals are not reproducible which is addressable using a multi-faceted testing framework.STATEMENT OF SIGNIFICANCESynthetic lethal screens have the power to identify new targets in cancer, although have thus far come up short of expectation. We use computational and experimental approaches to delineate principles for identifying robust synthetic lethal targets that could aid in the development of effective new therapeutic strategies for genetically defined cancers.

scholarly journals Profiling PRMT methylome reveals roles of hnRNPA1 arginine methylation in RNA splicing and cell growth

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Wen-juan Li ◽  
Yao-hui He ◽  
Jing-jing Yang ◽  
Guo-sheng Hu ◽  
Yi-an Lin ◽  
...  
Keyword(s):  
Alternative Splicing ◽  
Cell Growth ◽  
Rna Splicing ◽  
Synergistic Effects ◽  
Arginine Methylation ◽  
Type I ◽  
Prostate Cancer Cells ◽  
Cancer Cell Growth ◽  
Cancer Mutations ◽  
Substrate Spectrum

AbstractNumerous substrates have been identified for Type I and II arginine methyltransferases (PRMTs). However, the full substrate spectrum of the only type III PRMT, PRMT7, and its connection to type I and II PRMT substrates remains unknown. Here, we use mass spectrometry to reveal features of PRMT7-regulated methylation. We find that PRMT7 predominantly methylates a glycine and arginine motif; multiple PRMT7-regulated arginine methylation sites are close to phosphorylations sites; methylation sites and proximal sequences are vulnerable to cancer mutations; and methylation is enriched in proteins associated with spliceosome and RNA-related pathways. We show that PRMT4/5/7-mediated arginine methylation regulates hnRNPA1 binding to RNA and several alternative splicing events. In breast, colorectal and prostate cancer cells, PRMT4/5/7 are upregulated and associated with high levels of hnRNPA1 arginine methylation and aberrant alternative splicing. Pharmacological inhibition of PRMT4/5/7 suppresses cancer cell growth and their co-inhibition shows synergistic effects, suggesting them as targets for cancer therapy.

scholarly journals Interactions between highly conserved U2 small nuclear RNA structures and Prp5p, Prp9p, Prp11p, and Prp21p proteins are required to ensure integrity of the U2 small nuclear ribonucleoprotein in Saccharomyces cerevisiae.

1994 ◽  
Vol 14 (9) ◽  
pp. 6337-6349 ◽  
Author(s):  
S E Wells ◽  
M Ares
Keyword(s):  
Synthetic Lethality ◽  
Small Nuclear Rna ◽  
Rna Structures ◽  
Stem Loop ◽  
U2 Snrna ◽  
Small Nuclear Ribonucleoprotein ◽  
U2 Snrnp ◽  
Nuclear Rna ◽  
Nuclear Ribonucleoprotein

Binding of U2 small nuclear ribonucleoprotein (snRNP) to the pre-mRNA is an early and important step in spliceosome assembly. We searched for evidence of cooperative function between yeast U2 small nuclear RNA (snRNA) and several genetically identified splicing (Prp) proteins required for the first chemical step of splicing, using the phenotype of synthetic lethality. We constructed yeast strains with pairwise combinations of 28 different U2 alleles with 10 prp mutations and found lethal double-mutant combinations with prp5, -9, -11, and -21 but not with prp3, -4, -8, or -19. Many U2 mutations in highly conserved or invariant RNA structures show no phenotype in a wild-type PRP background but render mutant prp strains inviable, suggesting that the conserved but dispensable U2 elements are essential for efficient cooperative function with specific Prp proteins. Mutant U2 snRNA fails to accumulate in synthetic lethal strains, demonstrating that interaction between U2 RNA and these four Prp proteins contributes to U2 snRNP assembly or stability. Three of the proteins (Prp9p, Prp11p, and Prp21p) are associated with each other and pre-mRNA in U2-dependent splicing complexes in vitro and bind specifically to synthetic U2 snRNA added to crude splicing extracts depleted of endogenous U2 snRNPs. Taken together, the results suggest that Prp9p, -11p, and -21p are U2 snRNP proteins that interact with a structured region including U2 stem loop IIa and mediate the association of the U2 snRNP with pre-mRNA.

scholarly journals Using Yeast Synthetic Lethality To Inform Drug Combination for Malaria

2018 ◽  
Vol 62 (4) ◽  
Author(s):  
Suvitha Subramaniam ◽  
Christoph D. Schmid ◽  
Xue Li Guan ◽  
Pascal Mäser
Keyword(s):  
Plasmodium Falciparum ◽  
Drug Combination ◽  
Synthetic Lethality ◽  
Drug Combinations ◽  
Synthetic Lethal Interaction ◽  
Content Type ◽  
Synthetic Lethal ◽  
Gene Pairs ◽  
Phosphatidylinositol 4

ABSTRACT Combinatorial chemotherapy is necessary for the treatment of malaria. However, finding a suitable partner drug for a new candidate is challenging. Here we develop an algorithm that identifies all of the gene pairs of Plasmodium falciparum that possess orthologues in yeast that have a synthetic lethal interaction but are absent in humans. This suggests new options for drug combinations, particularly for inhibitors of targets such as P. falciparum calcineurin, cation ATPase 4, or phosphatidylinositol 4-kinase.

A Screen for Dynein Synthetic Lethals in Aspergillus nidulans Identifies Spindle Assembly Checkpoint Genes and Other Genes Involved in Mitosis

Genetics ◽  
1998 ◽  
Vol 149 (1) ◽  
pp. 101-116
Author(s):  
Vladimir P Efimov ◽  
N Ronald Morris
Keyword(s):  
Aspergillus Nidulans ◽  
Spindle Assembly Checkpoint ◽  
Genetic Interaction ◽  
Synthetic Lethality ◽  
Spindle Assembly ◽  
Nuclear Migration ◽  
Cytoplasmic Dynein ◽  
Vesicle Transport ◽  
Synthetic Lethal ◽  
Checkpoint Genes

Abstract Cytoplasmic dynein is a ubiquitously expressed microtubule motor involved in vesicle transport, mitosis, nuclear migration, and spindle orientation. In the filamentous fungus Aspergillus nidulans, inactivation of cytoplasmic dynein, although not lethal, severely impairs nuclear migration. The role of dynein in mitosis and vesicle transport in this organism is unclear. To investigate the complete range of dynein function in A. nidulans, we searched for synthetic lethal mutations that significantly reduced growth in the absence of dynein but had little effect on their own. We isolated 19 sld (synthetic lethality without dynein) mutations in nine different genes. Mutations in two genes exacerbate the nuclear migration defect seen in the absence of dynein. Mutations in six other genes, including sldA and sldB, show a strong synthetic lethal interaction with a mutation in the mitotic kinesin bimC and, thus, are likely to play a role in mitosis. Mutations in sldA and sldB also confer hypersensitivity to the microtubule-destabilizing drug benomyl. sldA and sldB were cloned by complementation of their mutant phenotypes using an A. nidulans autonomously replicating vector. Sequencing revealed homology to the spindle assembly checkpoint genes BUB1 and BUB3 from Saccharomyces cerevisiae. Genetic interaction between dynein and spindle assembly checkpoint genes, as well as other mitotic genes, indicates that A. nidulans dynein plays a role in mitosis. We suggest a model for dynein motor action in A. nidulans that can explain dynein involvement in both mitosis and nuclear distribution.

Sign in / Sign up

Export Citation Format

Share Document