Questions, Feedback & Help
Send us an email and we'll get back to you ASAP. Or you can read our Frequently Asked Questions.
30 results (0.009 seconds)
  • paper:
  • [
    Sci Rep,
    2024]
    Jujubae Fructus, the fruit of Ziziphus jujuba Mill has been used as one of the medicine food homology species for thousands of years in China. Studies have shown that the active ingredients of Jujubae Fructus have a variety of biological effects, but its role in the aging process still lacks knowledge. Here, we investigated the effect of Jujubae Fructus extract (JE) on Caenorhabditis elegans lifespan and its potential mechanism. The lifespan of C. elegans treated with JE was signifificantly increased in a dose-dependent manner. In addition, JE treatment prolonged the reproductive period and increased normal activity during aging in C. elegans. Similarly, JE supplementation also enhanced the resistance to heat and oxidative stress in C. elegans. Furthermore, the mutant worms' lifespan assays demonstrated that JE requires daf-16 to prolong lifespan. DAF-16::GFP analysis of TJ356 showed that JE treatment translocates DAF-16::GFP to nucleus in transgenic worms. By analyzing the downstream of daf-16, we identify that JE may regulate sod3 downstream of daf-16. Mutant worms' lifespan and transgenic reporter gene expression assays revealed that increasing SOD-3 expression was critical for extending longevity in C. elegans with JE therapy. Collectively, these data indicate that JE may have an important role in C. elegans longevity that is dependent on DAF-16 and SOD-3.
  • strain: RG559
  • Caenorhabditis elegans
  • strain: JIN810
  • Caenorhabditis elegans
  • strain: COP262
  • Caenorhabditis elegans
  • paper:
  • [
    Science,
    1994]
    A. Brooks et al. report that mortality increased exponentially for a cohort of 180,000 nematodes of the species Caenorhabditis elegans of the single genotype TJ1060 [spe-9(hc88) fer-15(b26)]. A closer look at the data reveals that from days 5 through 8 mortality increased at a rate of 0.58 +/- 0.0004, which is more than twice the rate thereafter (0.21 +/- 0.02). Such a "biphasic pattern," with death rates increasing rapidly at younger ages and more slowly at older ages, was also found in a genetically heterogeneous population of 79 recombinant-inbred (RI) strains.
  • paper:
  • [
    International C. elegans Meeting,
    1999]
    Proteome, Inc. is constructing a C. elegans proteome database that presents properties and functions for the entire set of C. elegans proteins, predicted to be approximately 19,000 in number (1). This database is built by expert curators who are reviewing the entire C. elegans literature and contains essentially all available knowledge for the characterized proteins of C. elegans (2). Here we describe use of the Yeast Proteome Database (YPD), a well-developed proteome database for S. cerevisiae , to annotate many of the uncharacterized proteins of C. elegans . Examples will be presented of knowledge transfer from well-characterized proteins in YPD to create informative C. elegans Protein Reports for as yet uncharacterized proteins. The knowledge transferred is the exhaustive biochemical, genetic and cell biology information on S. cerevisiae contained in the YPD, distilled by expert curation from the research literature about yeast proteins. The mechanism of transfer is the BLAST similarity of C. elegans proteins to S. cerevisiae proteins, and to Drosophila and human proteins. Since highly similar proteins in different organisms have like functions, uncharacterized C. elegans proteins can be predicted to have like functions of similar, well-characterized proteins in yeast. Protein similarities have also been used to build protein families in yeast and worm (3) and are also the basis for domain databases (e.g., Pfam). The C. elegans proteome database has expanded upon these sources to add additional protein family knowledge to the C. elegans Protein Reports. Functional genomic information from YPD can be used to predict potential functions of C. elegans proteins. Many transcript profile experiments from the yeast community are presented in YPD, and we plan, in the same manner, to make the C. elegans proteome database a repository for public functional genomic data. Tools for transcript profile analysis that already exist in YPD will be used for analysis of profiling experiments in C. elegans . 1. The C. elegans Sequencing Consortium, Science 282, 2012 (1998). 2. Roberg-Perez et al., this meeting. 3. Chervitz, et al., Science 282, 2022 (1998)
  • paper:
  • [
    International C. elegans Meeting,
    2001]
    In order to examine the process of sulfation in C. elegans, sulfation was inhibited chemically using sodium chlorate, and genetically using the process of RNA-mediated interference (RNAi). Sodium chlorate inhibition during early larval stages resulted in a dose-dependant developmental delay. BLAST searches of characterized sulfotransferases against the worm genome resulted in the identification of 4 putative sulfotransferases: C34F6.4 and F08B4.6 (previously identified: [1] and [2]), F40H3.5, and Y34B4A.e. RNAi of the putative N-deacetylase/N-sulfotransferase F08B4.6 resulted in "stacking" of eggs in the gonad, along with eggs laid at the 2- and 4-celled stage. RNAi of the putative hexuronic 2-O sulfotransferase C34F6.4 resulted in a shortened, bulbous gonad. These initial results indicate that sulfation may be important during development of C. elegans. [1] Shworak, NW, Liu, J, Fritze, LMS, Schwartz, JJ, Zhang, L, Logeart, D, Rosenberg, RD. JBC 272: 28008-19 (1997). [2] Kobayashi, M, Sugumaran, G, Liu, J, Shworak, NW, Silbert, JE, Rosenberg, RD. JBC 274: 10474-80 (1999).
  • paper:
  • [
    International Worm Meeting,
    2005]
    We are studying the properties of acetylcholine receptors in C. elegans vulval muscles using the genetically expressed calcium indicator cameleon. The worm is dissected using a technique adapted from Richmond and Jorgensen (1999). Animals are glued down in a perfusion chamber, a small incision made on the ventral side opposite the vulva and the viscera removed. This exposes the vulval muscles and allows the direct application of drugs to these muscles at physiological concentrations. Dissected vulval muscles continue to contract and give corresponding calcium transients. Wild type vulval muscles show a large increase in intracellular calcium in response to 500M nicotine or 100M levamisole. Levamisole receptor mutants, unc-29 and lev-1 do not respond to levamisole but show a smaller response to nicotine than wild type. Further experiments will be performed to determine the response to acetylcholine and the effect of different pharmacological blockers of nicotinic receptors. The effects of adaptation to repeated nicotine stimulation, or long term exposure to nicotine, will also be described. Richmond, JE. and Jorgensen, EM., Nat Neurosci. 1999 (9):791-7
  • paper:
  • [
    Exp Gerontol,
    1997]
    A recent report (Easton, 1995) showed that, at least for Mediterranean fruit flies, a Gompertz growth equation based on the increase in number of individuals that die is a better predictor of survival data than is the classical Gompertz survivorship model based on the decrease in number that survive (analysis of medfly data of Carey et al., 1992). In the growth model, the rate of increase of the number dead (i.e., the death rate) decreases exponentially with age. The poor fit of the classical model predicts "excess survival" of older members, but, when the scale of the better-fitting growth model is increased 2400x, such excess is now also evident as a small but distinctly separate cohort of the medfly subjects. The smaller population appears to be about 0.01% of the larger, and the death rate decreases about one-fourth as fast. Survival of the nematode C. elegans (Brooks et al., 1994) is also better predicted by the growth model, which also shows excess survival of the worms at great age.
  • paper:
  • [
    International Worm Meeting,
    2003]
    The active zone is a specialized presynaptic structure where vesicles containing neurotransmitters fuse with the plasma membrane, releasing the neurotransmitters to the post-synaptic membrane. At the EM level, electron dense active zones are surrounded by clusters of vesicles. A few components of the active zone have been identified such as UNC-10 (Koushika et al., 2001), UNC-13 (Richmond et al., 1999; Aravamudan et al., 1999) and SYD-2 (Zhen and Jin, 1999) but even fewer have been implicated in active zone establishment, differentiation or maintainance.syd-2 encodes a homolog of liprin- and has been shown to be a component of the active zone. Mutations in syd-2 give rise to larger active zones. At a previous meeting, we reported a SYD-2::GFP marker that could be used to visualize active zones in live animals. The SYD-2::GFP protein marker was placed under the promoter of unc-25 which expresses in GABAergic neurons. We have performed a SYD-2::GFP screen to identify a dditional factors involved in the formation of the active zone. An EMS mutagenesis screen was performed looking for mutations affecting the formation of the active zone. Approximately 2500 haploid genomes were screened and we are currently characterizing 5 isolated mutant alleles. hp77 and hp121 represent two loci on chromosome X, hp102 and hp198 represent two loci on chromosome IV and hp129 is on chromosome V. hp121 and hp102 have behavioural unc phenotypes, hp198 are slightly dumpy while hp77 and hp129 do not appear to have any behaviour or physical phenotypes. Initial characterization and phenotypic analysis will be presented on these mutants. It is our hope that the molecular characterization of these mutants will provide information on factors involved in the establishment, differentiation, and maintenance of active zones. Ultimately, this information will provide insight into the genetic pathways used to establish neural synapses in general.References: Aravamudan B, Fergestad T, Davis WS, Rodesch CK, and Broadie K. (1999) Nature Neuroscience. 2:965; Koushika SP, Richmond JE, Hadwiger G, Weimer RM, Jorgensen EM and Nonet M. (2001) Nature Neuroscience. 4:997-1005; Richmond JE, Davis WS and Jorgensen EM. (1999) Nature Neuroscience. 2:959-64; Zhen M and Jin Y. (1999) Nature. 401:371-5
load 10 more results