4 Papers found (0.008 seconds)

Marshall SDG et al. (2001) Dev Biol "Coordination of ges-1 expression between the Caenorhabditis pharynx and intestine."

Marshall SDG, McGhee JD

[

Dev Biol,

2001]

We have previously shown that the Caenorhabditis elegans gut-specific esterase gene (Ce-ges-1) has the unusual ability to be expressed in different modules of the embryonic digestive tract (anterior pharynx, posterior pharynx, and rectum) depending on sequence elements within the Ce-ges-1 promoter. In the present paper, we analyze the expression of the ges-1 homolog (Cb-ges-1) from the related nematode Caenorhabditis briggsae and show that Cb-ges-1 also has the ability to switch expression between gut and pharynx + rectum. The control of this expression switch centres on a tandem pair of WGATAR sites in the Cb-ges-1 5'-flanking region, just as it does in Ce-ges-1. We use sequence alignments and subsequent deletions to identify a region at the 3'-end of both Ce-ges-1 and Ce-ges-1 that acts as the ges-1 cryptic pharynx enhancer whose activity is revealed by removal of the 5' WGATAR sites. This region contains a conserved binding site for PHA-4 (the C. elegans ortholog of forkhead/HNF3 alpha, beta,gamma factors), which is expressed in all cells of the developing pharynx and a subset of cells of the developing rectum. We propose a model in which the normal expression of ges-1 is controlled by the gut-specific GATA factor ELT-2. We propose that, in the pharynx (and rectum), PHA-4 is normally bound to the ges-1 3'-enhancer sequence but that the activation function of PHA-4 is kept repressed by a (presently unknown) factor binding in the vicinity of the 5' WGATAR sites. We suggest that this control circuitry is maintained in Caenorhabditis because pharyngeal expression of ges-1 is advantageous only under certain developmental or environmental conditions.

Lu M et al. (2020) Oxid Med Cell Longev "Secoisolariciresinol Diglucoside Delays the Progression of Aging-Related Diseases and Extends the Lifespan of Caenorhabditis elegans via DAF-16 and HSF-1."

Chen JN, Zhou XG, Yang ZL, Zhu Q, Luo HR, Lu M, Wu GS, Tan L

[

Oxid Med Cell Longev,

2020]

Secoisolariciresinol diglucoside (SDG) is a phytoestrogen and rich in food flaxseed, sunflower seeds, and sesame seeds. Among the beneficial pharmacological activities of SDG on health, many are age related, such as anticancer, antidiabetes, antioxidant, and neuroprotective effects. Thus, we investigated if SDG had an effect on antiaging in Caenorhabditis elegans (C. elegans). Our results showed that SDG could extend the lifespan of C. elegans by up to 22.0%, delay age-related decline of body movement, reduce the lethality of heat and oxidative stress, alleviate dopamine neurodegeneration induced by 6-hydroxydopamine (6-OHDA), and decrease the toxicity of A protein in C. elegans. SDG could increase the expression of the downstream genes of DAF-16, DAF-12, NHR-80, and HSF-1 at mRNA level. SDG could not extend the lifespan of mutants from genes daf-16, hsf-1, nhr-80, daf-12, glp-1, eat-2, and aak-2. The above results suggested that SDG might enhance the stress resistance, delay the progression of aging-related diseases, and extend the lifespan of C. elegans via DAF-16 and HSF-1.

Zhang L et al. (2012) Genomics Proteomics Bioinformatics "A modified statistically optimal null filter method for recognizing protein-coding regions."

Wang S, Tian F, Zhang L

[

Genomics Proteomics Bioinformatics,

2012]

Computer-aided protein-coding gene prediction in uncharacterized genomic DNA sequences is one of the most important issues of biological signal processing. A modified filter method based on a statistically optimal null filter (SONF) theory is proposed for recognizing protein-coding regions. The square deviation gain (SDG) between the input and output of the model is used to identify the coding regions. The effective SDG amplification model with Class I and Class II enhancement is designed to suppress the non-coding regions. Also, an evaluation algorithm has been used to compare the modified model with most gene prediction methods currently available in terms of sensitivity, specificity and precision. The performance for identification of protein-coding regions has been evaluated at the nucleotide level using benchmark datasets and 91.4%, 96%, 93.7% were obtained for sensitivity, specificity and precision, respectively. These results suggest that the proposed model is potentially useful in gene finding field, which can help recognize protein-coding regions with higher precision and speed than present algorithms.

Kobayashi H et al. (1996) J Biotechnol "Bioprocessing in microgravity: free flow electrophoresis of C. elegans DNA."

Kobayashi H, Ishii N, Nagaoka S

[

J Biotechnol,

1996]

Free flow electrophoresis of a nematode C. elegans DNA was carried out on the space shuttle flight STS65/Colombia. During the processes of the experiment, the house keeping data of the FFEU and the electrophoretic migration profiles were monitored at POCC (Payload Operations Control Center) of MSFC (Marshall Space Flight Center, Alabama) according to the real-time down-link system. The three dimensional electropherogram (3DEP) on the basis of the down-linked data showed some trouble with the apparatus but three sequential experiments indicated this disturbance of the apparatus is rather preferably stable. Comparing post-flight analyses of the DNA component fractionated, that is, amplification by PCR method, it revealed that the DNAs were separated approximately into two peaks: one of them contained seven-fold higher content of DNA estimated by a sod-4 gene probe than an unc-6 gene probe. These results suggested that this separation technique could be still more effective for the separation of biological macromolecules such as DNA, and the efficiency of separation of the free flow electrophoresis under microgravity environment was useful.