Expression profiling in N2 (wild-type) early embryo

Determination of gene expression levels in wild-type early embryo. First published in Rechtsteiner et al. 2010 PLoS Genetics.

C. elegans embryonic timecourse in wt and mutant embryos

This series of samples comprises multiple early embryonic time courses for C. elegans. Time courses consisting of 10 time points each for 4 different genotypes are included: wild-type (strain N2 grown on E. coli strain OP50), pie-1(zu154) (progeny of homozygous mutant mothers [Unc] of strain JJ532 grown on E. coli strain OP50), pie-1(zu154);pal-1(RNAi) (progeny of homozygous mutant mothers [Unc] of strain JJ532 grown on E. coli strain HT115 expressing pal-1 hairpin RNA), and mex-3(zu155);skn-1(RNAi) (progeny of homozygous mutant mothers [Dpy] of strain JJ518 grown on E. coli strain HT115 expressing skn-1 hairpin RNA). Embryos were manually staged by morphology at the 4-cell stage and allowed to develop in water for defined amounts of time at 22 degrees C. RNA was amplified as described (Baugh et al. Development, 2003; Baugh et al. Nucleic Acids Research, 2001). This series of samples comprises all replicate data reported by Baugh et al. (Development, 2005). Keywords: time-course

A cellular surveillance and defense system that delays aging phenotypes in C. elegans.

Aging is an important risk factor for disease and is accompanied by the decline of many physiological characteristics, including physical performance. One of the most powerful tests of physical ability in elderly humans is the short physical performance battery (SPPB) (Guralnik et al., 1994), an assessment of the maximum exercise capacity of lower extremities over a short period of time. A similar metric of maximum velocity (MV) in a short period (30s) is proposed as an equally informative measurement inC. elegans (Hahm et al., 2015). MV declines with age, correlates well with longevity, accurately reports movement ability, and importantly, is predictive of future longevity (Hahm et al., 2015).Here, we characterized the differences in gene expression between high MV group and low MV group of the same age in C. elegans. The genes related to nucleosomes and involved in regulatory processes, including transcriptional regulation (chromatin assembly, regulation of RNA metabolic process and regulation of transcription), and neuronal signaling (neurogenesis, axon guidance, and regulation of neurotransmitter levels) were up-regulated in low MV group compared to high MV group. In contrast, genes belonged to metabolic processes and mitochondria were down-regulated in low MV group compared to high MV group.

Microarray expression profiling of C. elegans N2 L4 control(RNAi) vs. mdt-15(RNAi)

We previously showed that the C. elegans Mediator subunit MDT-15 impacts expression of select genes involved in fatty acid (FA) metabolism (Taubert et al, Genes & Dev, 2006). To comprehensively identify processes downstream of MDT-15 in an unbiased manner, we set out to globally discover new MDT-15-dependent genes. Keywords: Expression profiling, RNAi depletion

Age-related behaviors have distinct transcriptional profiles in C. elegans

There has been a great deal of interest in identifying potential biomarkers of aging (Butler et al. 2004). Biomarkers of aging would be useful to predict potential vulnerabilities in an individual that may arise well before they are chronologically expected, due to idiosyncratic aging rates that occur between individuals. Prior attempts to identify biomarkers of aging have often relied on the comparisons of long-lived animals to a wild-type control (Dhahbi et al. 2004). However, the effect of interventions in model systems that prolong lifespan (such as single gene mutations, or caloric restriction) can sometimes be difficult to interpret due to the manipulation itself having multiple unforeseen consequences on physiology, unrelated to aging itself (Gems et al. 2002; Partridge & Gems 2006). The search for predictive biomarkers of aging therefore is problematic, and the identification of metrics that can be used to predict either physiological or chronological age would be of great value (Butler et al. 2004). One methodology which has been used to identify biomarkers for numerous pathologies is gene expression profiling. Here, we report whole-genome expression profiles of individual wild-type Caenorhabditis elegans covering the entire wild-type nematode life span. Individual nematodes were scored for either age-related behavioral phenotypes, or survival, and then subsequently associated with their respective gene expression profiles. This facilitated the identification of transcriptional profiles that were highly associated with either physiological or chronological age. Overall, our approach serves as a paradigm for identifying potential biomarkers of aging in higher organisms that can be repeatedly sampled throughout their lifespan. The full normalized data set with expression values for all genes of all individual worms at all ages (104 worms/arrays) is available as a 28Mb download as a supplementary file on this page (GSE12290.txt). Keywords: time couse

Global profile of germline gene expression in C. elegans

We used DNA microarrays to profile gene expression patterns in the C. elegans germline and identified 1416 germline-enriched transcripts that define three groups. The sperm-enriched group contains an unusually large number of protein kinases and phosphatases. The oocyte-enriched group includes potentially new components of embryonic signaling pathways. The germline-intrinsic group, defined as genes expressed similarly in germlines making only sperm or only oocytes, contains a family of piwi-related genes that may be important for stem cell proliferation. Finally, examination of the chromosomal location of germline transcripts revealed that sperm-enriched and germline-intrinsic genes are nearly absent from the X chromosome, but oocyte-enriched genes are not. This research has been described more fully in Reinke V et al.(2000) Mol Cell 6:605-16 Keywords: other

Transcriptome profiling of slr-2, C.elegans C2H2 Zn-finger

Our slr-2 dataset showed strong overrepresentation of genes previously identified in a serial analysis of gene expression (SAGE) intestinal library (McGhee et al., 2006) (p << 0.01); 812 genes were common to both data sets. Consistent with the deregulation of intestinal genes, we observed repression of several important metabolic pathways, including the TOR and insulin signaling networks, suggesting that slr-2(ku297) mutants experience metabolic stress. We also compared differentially regulated genes in slr-2 and lin-35 single mutants. Again, we saw a statistically significant overlap (p-value < 0.01); 261 genes were present in both data sets. Strikingly, > 75% of genes common both datasets showed expression changes in the same direction, although the common dataset contained an approximately equal mixture of up and downregulated genes. Furthermore, more than fifty genes common to the lin-35 and slr-2 datasets are known to have intestinal-associated functions. That some of these common intestinal genes were absent from the gut SAGE library could be due to differences in the developmental stage of the animals assayed (adults versus L1s) as well as experimental approaches (SAGE versus microarrays) Keywords: analysis of staged mutant worms

Genetic Analysis of Pathways Regulated by the von Hippel-Lindau Tumor Suppressor in Caenorhabditis elegans

The von Hippel-Lindau (VHL) tumor suppressor functions as a ubiquitin ligase that mediates proteolytic inactivation of hydroxylated a subunits of hypoxia-inducible factor (HIF). Although studies of VHL defective renal carcinoma cells suggest the existence of other VHL tumor suppressor pathways, dysregulation of the HIF transcriptional cascade has extensive effects that make it difficult to distinguish whether, and to what extent, observed abnormalities in these cells represent effects on pathways that are distinct from HIF. Here, we report on a genetic analysis of HIF dependent and independent effects of VHL inactivation by studying gene expression patterns in C. elegans. We show tight conservation of the HIF-1/VHL-1/EGL-9 hydroxylase pathway. However, persisting differential gene expression in hif-1 versus hif-1; vhl-1 double mutant worms clearly distinguished HIF-1 independent effects of VHL-1 inactivation. Genomic clustering, predicted functional similarities, and a common pattern of dysregulation in both vhl-1 worms and a set of mutants (dpy-18, let-268, gon-1, mig-17 and unc-6), with different defects in extracellular matrix formation, suggest that dysregulation of these genes reflects a discrete HIF-1 independent function of VHL-1 that is connected with extracellular matrix function. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Bishop T, Lau KW, Epstein AC, Kim SK, Jiang M, O'rourke D, Pugh CW, Gleadle JM, Taylor MS, Hodgkin J, Ratcliffe PJ, Genetic Analysis of Pathways Regulated by the von Hippel-Lindau Tumor Suppressor in Caenorhabditis elegans., Bishop T, et al. (2004) PLoS Biol 2(10):e289, 2004-10-01, http: