Apela (also referred to as Elabela, Ende and Toddler) is a small signaling peptide that activates the G protein-coupled receptor Aplnr. We used CRISPR/Cas9 to generate a null, reporter-expressing allele, in order to study the role of Apela in the developing mouse embryo. We found that loss of Apela results in low penetrance cardiovascular defects that manifest after the onset of circulation. Targeted Apela null alleles exhibited different transcriptional activity depending on the presence or absence of a Neomycin selection cassette. These are referred to as Apela KO NEO-IN and Apela KO NEO-OUT strains, respectively. Despite subtle phenotypic characteristics that were unique to the NEO-OUT mutants, both Apela null strains shared the same variable expressivity of cardiovascular defects and the same penetrance of embryonic lethality. To investigate the earliest regulatory events leading to physical abnormalities in Apela mutants, we performed RNA-Seq on whole stage-matched and morphologically normal E7.5 embryos (3 wild-type, 6 Apela KO NEO-IN, and 6 Apela KO NEO-OUT individuals). We chose this stage because Apela is initially expressed in the embryo at late gastrulation, shortly after the emergence of extraembryonic mesoderm progenitors. Since modification of the Apela locus may influence the expression of neighboring genes, we examined the expression of upstream and downstream sequences and found no significant difference in their expression. Downregulated genes of interest included several mitochondrial genes, Ceacam2, Ulk4, and Mov10l1. Upregulated genes included the vascular endothelial growth factor Vegfc. Principal component analysis identified outliers (KO1 and KO9), both of which expressed lower levels of mesoderm markers. KO9 was further characterized by aberrant upregulation of erythroid and myeloid markers. This finding was confirmed in our study by qRT-PCR analysis of additional Apela null individuals. Overall design: 15 individual embryos were analyzed at E7.5. Embryos were stage-matched according to morphological landmarks. Control samples were wild-type (n=3), and Apela KO samples were null embryos from the NEO-IN (n=6, ‘KO1-6’) and NEO-OUT (n=6, ‘KO7-12) mutant strains. Whole embryos (including embryonic and extraembryonic tissues) were used for the analysis. Apela KO samples were isolated from homozygous KO intercrosses and therefore did not require genotyping.
Loss of Apela Peptide in Mice Causes Low Penetrance Embryonic Lethality and Defects in Early Mesodermal Derivatives.
Specimen part, Cell line, SubjectView Samples
Many new alternative splice forms have been detected at the transcript level using next generation sequencing (NGS) methods, especially RNA-Seq, but it is not known how many of these transcripts are being translated. Leveraging the unprecedented capabilities of NGS, we collected RNA-Seq and proteomics data from the same cell population (Jurkat cells) and created a bioinformatics pipeline that builds customized databases for the discovery of novel splice-junction peptides. Results: Eighty million paired-end Illumina reads and ~500,000 tandem mass spectra were used to identify 12,873 transcripts (19,320 including isoforms) and 6,810 proteins. We developed a bioinformatics workflow to retrieve high-confidence, novel splice junction sequences from the RNA data, translate these sequences into the analogous polypeptide sequence, and create a customized splice junction database for MS searching. Overall design: Jurkat T-cell mRNA was analyzed on an Illumina HiSeq2000. ~80 million paired end reads (2x200bp, ~350bp lengths) were collected.
Discovery and mass spectrometric analysis of novel splice-junction peptides using RNA-Seq.
Cell lineView Samples
BACKGROUND: Climate change will lead in the future to an occurrence of heat waves with a higher frequency and duration than observed today, which has the potential to cause severe damage to seedlings of temperate maize genotypes. In this study, we aimed to (I) assess phenotypic variation for heat tolerance of temperate European Flint and Dent maize inbred lines, (II) investigate the transcriptomic response of temperate maize to linearly increasing heat levels and, (III) identify genes associated with heat tolerance in a set of genotypes with contrasting heat tolerance behaviour. RESULTS: Strong phenotypic differences with respect to heat tolerance were observed between the examined maize inbred lines on a multi-trait level. We identified 607 heat responsive genes as well as 39 heat tolerance genes. CONCLUSION: Our findings indicate that individual inbred lines developed different genetic mechanisms in response to heat stress. We applied a novel statistical approach enabling the integration of multiple genotypes and stress levels in the analysis of abiotic stress expression studies. Overall design: Identifcation of differentially expressed genes between 8 genotypes and 3 heat levels
Genome-wide expression profiling and phenotypic evaluation of European maize inbreds at seedling stage in response to heat stress.
Specimen part, SubjectView Samples
Ethanol is a well-known teratogen. While this teratogenic potential is well-characterized clinically, the mechanisms through which ethanol exposure results in developmental defects remain unclear. Here we use the zebrafish model to elucidate eye-specific mechanisms that may underlie ethanol-mediated microphthalmia (reduced eye size), using time-series microarray analysis of gene expression of eye tissues of embryos exposed to 1.5% ethanol vs. untreated embryos. We identified 62 genes differentially expressed in ethanol-treated as compared to control zebrafish eyes from all sampling times over the period of retinal neurogenesis (24-48 hours post-fertilization). Application of the EDGE (extraction of differential gene expression) algorithm identified over 3000 genes differentially expressed over developmental time in ethanol-treated embryo eyes as compared to untreated embryo eyes. These lists included several genes indicating a mis-regulated cellular stress response (heat shock response) due to ethanol exposure. Combined treatment with sub-threshold levels of ethanol and a morpholino (MO) targeting heat shock factor 1 (hsf-1) mRNA resulted in a microphthalmic phenotype, suggesting convergent molecular pathways. Manipulation of the heat shock response by thermal preconditioning partially prevented ethanol-mediated microphthalmia while maintaining Hsf-1 expression. Together these data are consistent with roles for reduced Hsf-1 in mediating microphthalmic effects of embryonic ethanol exposure in zebrafish.
Eye-specific gene expression following embryonic ethanol exposure in zebrafish: roles for heat shock factor 1.
Specimen part, TreatmentView Samples
The signaling molecule retinoic acid (RA) regulates rod and cone photoreceptor fate, differentiation, and survival. The purpose of this study was to identify eye-specific genes controlled by RA during photoreceptor differentiation in the zebrafish.
Retinoic Acid Signaling Regulates Differential Expression of the Tandemly-Duplicated Long Wavelength-Sensitive Cone Opsin Genes in Zebrafish.
Specimen partView Samples
Neonatal rat ventricular cardiomyocytes (NRVCMs) were stretched biaxially (112%/24h) or stimulated with phenylephrine (PE, 50 uM), both resulting in a similar degree of hypertrophy. Unstretched NRVCMs served as negative control. Affymetrix microarray analysis revealed 164 genes more than 2.0-fold up- and 21 genes less than 0.5-fold downregulated (p<0.01). Differential expression was confirmed by real-time PCR. Several genes of the fetal gene program, i.e. BNP (4.2-fold, all p<0.05) were induced by stretch as well as PE. We also verified the upregulation of known stretch-responsive genes, including HSP70 (20.9x) and c-myc (3.0x). Moreover, we identified genes exclusively induced by stretch, such as the cardioprotective and antihypertrophic cytokine GDF15 (24.8x) and the antihypertrophic factor heme oxygenase 1 (Hmox1, 10.8x; both confirmed on protein level). Of note, neither PE nor endothelin-1 were able to upregulate GDF15 and Hmox1, while angiotensin II significantly induced both genes. Conversely, addition of the AT1 receptor blocker irbesartan markedly blunted stretch-mediated GDF15 and Hmox1 induction, suggesting that the angiotensin II receptor mediates stretch-dependent signals.
Gene expression pattern in biomechanically stretched cardiomyocytes: evidence for a stretch-specific gene program.
No sample metadata fieldsView Samples
CD8+ tumor infiltrating T cells (TIL) lack effector-phase functions due to defective proximal TCR-mediated signaling shown to result from inactivation of p56lck kinase. We identify a novel interacting partner for p56lck in nonlytic TIL, Protocadherin-18 (pcdh18), and show that pcdh18 is transcribed upon in vitro or in vivo activation of CD8+ central memory T cells (CD44+CD62LhiCD127+) coincident with conversion into effector memory cells (CD44+CD62LloCD127+). Expression of pcdh18 in primary CD8+ effector cells induces the phenotype of nonlytic TIL: defective; proximal TCR signaling, cytokine secretion, and cytolysis; and enhanced AICD. pcdh18 contains a motif (centered at Y505) shared with src kinases (QGQYQP) which is required for the inhibitory phenotype. Thus, pcdh18 is a novel marker of CD8+ effector memory T cells expressed upon cell activation that can function as a negative regulator by restricting the effector phase.
Protocadherin-18 is a novel differentiation marker and an inhibitory signaling receptor for CD8+ effector memory T cells.
Sex, Age, Specimen part, Treatment, TimeView Samples
comparison of expression of wildtype lungs and lungs with hypomorphic expression of nmyc. the lungs were pooled from several biological samples. The hypomorphoic mutant was orignally published in Moens CB et al [PMID: 1577267]. this is part of a larger collection of data comparing nmyc misexpression in the lung (gain of fucntion) and protein expression in the hypomorphic lungs.
Integrated proteomic and transcriptomic profiling of mouse lung development and Nmyc target genes.
No sample metadata fieldsView Samples
We tested how complete or partial loss of endophilin A1, A2 and A3 affects gene expression in mouse hippocampus. Total loss of endophilin (triple knock-outs, TKO) was assessed in newborn mice, since the TKO mice only survive only several hours after birth. Partial loss of endophilin (endoA1,A2 double knock-out, DKO) was assessed between Overall design: 2-3 weeks of age (p13-21).
Endophilin-A Deficiency Induces the Foxo3a-Fbxo32 Network in the Brain and Causes Dysregulation of Autophagy and the Ubiquitin-Proteasome System.