Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

RNA expression profile (RNA-Seq) in mouse colonic epithelium expressing endogenouse K-Ras-WT or oncogenic K-Ras-G12D

ABSTRACT: K-Ras is frequently hyperactivated in human cancers through gain-of-function mutations that drive tumorigenesis. K-RasG12D, the most common oncogenic K-Ras allele, triggers massive transcriptomic and proteomic changes in the murine colon. Here, we report a comprehensive profile of physiological miRNA targets in murine colonic epithelium and tumor expressing K-RasG12D. Combining it with transcriptional, transcriptomic, and proteomic landscapes, we uncover a K-RasG12D-induced global suppression of miRNA activity that up-regulates hundreds of genes post-transcriptionally. K-RasG12D suppresses Csnk1a1 and Csnk2a1, which can decrease Ago2 phosphorylation at Ser825/829/831/835. Hypo-phosphorylated Ago2 increases binding with mRNA, reducing its regulatory activity by locking Ago2 in a small set of target transcripts. While expanding the repertoire of miRNA targets identified, it functionally decreases active Ago2, resulting in global de-repression of miRNA targets. Our findings establish a regulatory relationship among K-Ras, Csnk1a1/Csnk2a1, and Ago2 that provides a mechanistic link between oncogenic K-Ras and the up-regulation of hundreds of miRNA targets.

ORGANISM(S): Mus musculus

PROVIDER: GSE189702 | GEO | 2022/05/13

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

RNA expression profile (RNA-Seq) in mouse colonic tumor expressing endogenouse K-Ras-WT or oncogenic K-Ras-G12D

Project description:K-Ras is frequently hyperactivated in human cancers through gain-of-function mutations that drive tumorigenesis. K-RasG12D, the most common oncogenic K-Ras allele, triggers massive transcriptomic and proteomic changes in the murine colon. Here, we report a comprehensive profile of physiological miRNA targets in murine colonic epithelium and tumor expressing K-RasG12D. Combining it with transcriptional, transcriptomic, and proteomic landscapes, we uncover a K-RasG12D-induced global suppression of miRNA activity that up-regulates hundreds of genes post-transcriptionally. K-RasG12D suppresses Csnk1a1 and Csnk2a1, which can decrease Ago2 phosphorylation at Ser825/829/831/835. Hypo-phosphorylated Ago2 increases binding with mRNA, reducing its regulatory activity by locking Ago2 in a small set of target transcripts. While expanding the repertoire of miRNA targets identified, it functionally decreases active Ago2, resulting in global de-repression of miRNA targets. Our findings establish a regulatory relationship among K-Ras, Csnk1a1/Csnk2a1, and Ago2 that provides a mechanistic link between oncogenic K-Ras and the up-regulation of hundreds of miRNA targets.

2022-05-13 | GSE189704 | GEO

Chromatin accessbility profile (ATAC-Seq) in mouse colonic epithelium and tumor expressing endogenouse K-Ras-WT or oncogenic K-Ras-G12D

2022-05-13 | GSE189699 | GEO

Halo-enhanced Ago2 pulldown (HEAP) to identify miRNA targets in murine colonic tumor +/- oncogenic K-Ras-G12D

2022-05-13 | GSE189701 | GEO

Halo-enhanced Ago2 pulldown (HEAP) to identify miRNA targets in murine colonic epithelium +/- oncogenic K-Ras-G12D

2022-05-13 | GSE189700 | GEO

RNA expression profile (RNA-Seq) in mouse colonic tumors expressing endogenous K-Ras-WT, K-Ras-G12D, or K-RAS-G12D/K104Q

Project description:Ras proteins are GTPases that regulate a wide range of cellular processes. The activity of Ras is dependent on its nucleotide-binding status, which is modulated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Previously, we demonstrated that mutation of lysine 104 to glutamine (K104Q) attenuates the transforming capacity of oncogenic K-Ras by interrupting GEF induced nucleotide exchange. To assess the effect of this mutation in vivo, we used CRISPR/Cas9 to generate mouse models carrying the K104Q point mutation in wild-type and conditional K- RasLSL-G12D alleles. Homozygous animals for K104Q were viable, fertile, and arose at Mendelian frequency, indicating that K104Q is not a complete loss of function mutation. Consistent with our previous findings from in vitro studies, however, the oncogenic activity of K-RasG12D was significantly attenuated by mutation at K104. These data demonstrate that lysine at position 104 is critical for the full oncogenic activity of mutant K-Ras and suggest that modification at K104, for example acetylation, may also regulate its activity. Using biochemical and structural analysis, we found that the G12D and K104Q mutations cooperate to suppress GEF-mediated nucleotide exchange, explaining the preferential effect of K104Q on oncogenic K-Ras. Furthermore, we found that K104 site forms allosteric network with three residues (M72, R73 and G75) on 2 helix at switch II. Intriguingly, point mutation at glutamine 75 to alanine (G75A) showed strong negative regulatory effect on K-RasG12D. Collectively, modulating these sites may provide a unique therapeutic approach in cancer expressing mutant K-Ras.

2023-06-01 | GSE233945 | GEO

Halo-enhanced Ago2 pulldown (HEAP) to identify miRNA targets in murine colonic tumor +/- oncogenic K-Ras-G12D

Project description:Halo-enhanced Ago2 pulldown (HEAP) to identify miRNA targets in murine colonic tumor +/- oncogenic K-Ras-G12D

| PRJNA784253 | ENA

Halo-enhanced Ago2 pulldown (HEAP) to identify miRNA targets in murine colonic epithelium +/- oncogenic K-Ras-G12D

Project description:Halo-enhanced Ago2 pulldown (HEAP) to identify miRNA targets in murine colonic epithelium +/- oncogenic K-Ras-G12D

| PRJNA784254 | ENA

An Argonaute phosphorylation cycle promotes microRNA-mediated silencing [polyA RNA-seq]

Project description:MicroRNAs (miRNAs) perform critical functions in normal physiology and disease by associating with Argonaute proteins and downregulating partially complementary messenger RNAs (mRNAs). To identify new regulators of the miRNA pathway, we employed CRISPR-Cas9 genome-wide loss-of-function screening coupled with a fluorescent reporter of miRNA activity. Iterative rounds of screening revealed a novel mechanism whereby target engagement by Argonaute 2 (AGO2) triggers its hierarchical, multi-site phosphorylation by CSNK1A1 on a set of highly conserved residues (S824-S834), followed by rapid dephosphorylation by the ANKRD52-PPP6C phosphatase complex. Although genetic and biochemical studies demonstrated that AGO2 phosphorylation on these residues inhibits target mRNA binding, inactivation of this phosphorylation cycle globally impairs miRNA-mediated silencing. Analysis of the transcriptome-wide binding profile of non-phosphorylatable AGO2 revealed a dramatic expansion of the target repertoire bound at steady-state, effectively reducing the active pool of AGO2 on a per target basis. These findings support a model in which an AGO2 phosphorylation cycle stimulated by target engagement regulates miRNA:target interactions to maintain the global efficiency of miRNA-mediated silencing.

2017-01-17 | GSE89940 | GEO