The control of mRNA stability plays a central role in regulating gene expression. In metazoans, the earliest stages of development are driven by maternally supplied mRNAs. The degradation of these maternal mRNAs is critical for promoting the maternal-to-zygotic transition of developmental programs, although the underlying mechanisms are poorly understood in vertebrates. Here, we characterized maternal mRNA degradation pathways in zebrafish using a transcriptome analysis and systematic reporter assays. Our data demonstrate that ORFs enriched with uncommon codons promote deadenylation by the CCR4-NOT complex in a translation-dependent manner. This codon-mediated mRNA decay is conditional on the context of the 3' UTR, with long 3' UTRs conferring resistance to deadenylation. These results indicate that the combined effect of codon usage and 3' UTR length determines the stability of maternal mRNAs in zebrafish embryos. Our study thus highlights the codon-mediated mRNA decay as a conserved regulatory mechanism in eukaryotes. Overall design: zebrafish embryonic mRNA profile at 2 different stages (2 hpf and 6 hpf) in wildtype and 3 additional conditions (miR-430 inhibition, RNApol II inhibition and CNOT7 inhibition) at 6 hpf. All experiments are performed as triplicates
Codon Usage and 3' UTR Length Determine Maternal mRNA Stability in Zebrafish.
No sample metadata fields
View Sampleswe determined the contribution of the decapping enzyme Dcp2 to maternal mRNA clearance in zebrafish embryos by overexpressing a dominant-negative form of Dcp2. Overall design: zebrafish embryonic mRNA profile at 6 hpf in mock-inejcted or Dcp2-DN expressing embryos. Experiments are performed as triplicates.
Pervasive yet nonuniform contributions of Dcp2 and Cnot7 to maternal mRNA clearance in zebrafish.
No sample metadata fields
View SamplesCutaneous malignant melanoma is among the most deadly human cancers, broadly resistant to most clinical therapies. A majority of patients with BRAFV600E melanomas respond well to inhibitors such as vemurafenib, but all ultimately relapse. Moreover, there are no viable treatment options available for other non-BRAF melanoma subtypes in the clinic. A key to improving treatment options lies in a better understanding of mechanisms underlying melanoma progression, which are complex and heterogeneous. In this study we perform gene expression profilling of highly and poorly malignant melanocytic tumors from genetically engineered mouse models to discover important drivers of cancer progression.
Integrated Genomics Identifies miR-32/MCL-1 Pathway as a Critical Driver of Melanomagenesis: Implications for miR-Replacement and Combination Therapy.
Specimen part
View SamplesIn the present study, we demonstrate that hMSCs migrate toward human keratinocytes as well as toward conditioned medium from cultured human keratinocytes (KCM) indicating that the hMSCs can respond to signals from keratinocytes. Incubation of hMSCs with KCM induced dermal myofibroblast like differentiation characterized by expression of cytoskeletal markers vinculin and F-actin filaments with increased expression of alpha smooth muscle actin. We then examined the therapeutic efficacy of hMSCs in wound healing in two animal models representing normal and chronic wound healing. Accelerated wound healing, as determined by quantitative measurements of wound area, was observed when hMSCs and KCM exposed hMSCs (KCMSCs) were injected near the site of incisional/excisional wounds in nondiabetic athymic and NOD/SCID mice as compared with normal human fetal lung fibroblast WI38 cells or saline control induced wound healing.
Keratinocyte Induced Differentiation of Mesenchymal Stem Cells into Dermal Myofibroblasts: A Role in Effective Wound Healing.
No sample metadata fields
View SamplesMicroRNAs comprise 1-3% of all vertebrate genes, but their in vivo functions and mechanisms of action remain largely unknown. Zebrafish miR-430 is expressed at the onset of zygotic transcription and regulates morphogenesis during early development. Using a microarray approach and in vivo target validation, we find that miR-430 directly regulates several hundred target mRNAs. Targets are highly enriched for maternal mRNAs that accumulate in the absence of miR-430. We also show that miR-430 accelerates the deadenylation of target mRNAs. These results suggest that miR-430 facilitates the deadenylation and clearance of maternal mRNAs during early embryogenesis.
Zebrafish MiR-430 promotes deadenylation and clearance of maternal mRNAs.
No sample metadata fields
View SamplesMM1S cells have been cultured under normoxic and hypoxic conditions, and gene expression profiling has been performed using the Affymetrix Human Genome U133 Plus 2.0 array.
Metabolic signature identifies novel targets for drug resistance in multiple myeloma.
Cell line
View SamplesHere we identify a Dicer-independent miRNA biogenesis pathway that employs the slicer catalytic activity of Argonaute2 (Ago2). To uncover Dicer-independent miRNAs, we sequenced small RNAs in wild type, maternal-zygotic dicer (MZdicer) and MZago2 mutants, using zebrafish as a model system. We find that, in contrast to other miRNAs, miR-451 levels were increased in MZdicer but drastically reduced in the MZago2 mutants. We show that pre-miR-451 processing requires Ago2 catalytic activity in vivo. MZago2 mutant embryos display delayed erythrocyte maturation that can be rescued by wild type Ago2 or miR-451 duplex but not catalytically dead Ago2. We propose that Ago2-mediated cleavage of a subset of pre-miRNAs, followed by uridylation and trimming, generates functional miRNAs in a Dicer-independent manner. Overall design: Examination of small RNAs (18 to 35 nucleotides) in 3 different zebrafish genotypes (wild type, MZago2, MZdicer) at 48 hours post-fertilization.
A novel miRNA processing pathway independent of Dicer requires Argonaute2 catalytic activity.
No sample metadata fields
View SamplesLeaf samples were used. We exposed young seedlings to NaCl and drought.
Identification of cis-regulatory elements associated with salinity and drought stress tolerance in rice from co-expressed gene interaction networks.
Specimen part
View SamplesC1013G/CXCR4 variant has been inserted into BCWM.1 cells, and gene expression profile has been performed on the mutated cells and on the parental cells.
C1013G/CXCR4 acts as a driver mutation of tumor progression and modulator of drug resistance in lymphoplasmacytic lymphoma.
Cell line
View SamplesMYC is a major oncogenic driver of Multiple Myeloma (MM) and yet almost no therapeutic agents exist that target MYC in MM. Here we report that the let-7 biogenesis inhibitor LIN28B correlates with MYC expression in MM and is associated with adverse outcome. We also demonstrate that the LIN28B/let-7 axis modulates the expression of MYC, itself a let-7 target. Further, perturbation of the axis regulates the proliferation of MM cells in vivo in a xenograft tumor model. RNA sequencing and gene set enrichment analyses of CRISPR-engineered cells further suggest that the LIN28/let-7 axis regulates MYC and cell cycle pathways in MM. We provide proof-of-principle for therapeutic regulation of MYC through let-7 with an LNA-GapmeR containing a let-7b mimic in vivo, demonstrating that high levels of let-7 expression repress tumor growth by regulating MYC expression. These findings reveal a novel mechanism of therapeutic targeting of MYC through the LIN28B/let-7 axis in MM that may impact other MYC dependent cancers as well. Overall design: RNA sequencing of MOLP-8 cells transduced with lentiCRISPRv2 scrambled control or containing a sgRNA against LIN28B. Both control and LIN28B KO cells were sequenced in triplicate.
The LIN28B/let-7 axis is a novel therapeutic pathway in multiple myeloma.
No sample metadata fields
View Samples