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Wibisono, P.

Publications and source records attributed to Wibisono, P..

3 recordsLinked to original sources

Neural G protein-coupled receptor OCTR-1 mediates temperature effects on longevity by regulating immune response genes in C. elegans

Researchers have long known that many animals live longer in colder climates than in warmer climates. The inverse relationship between temperature and lifespan was traditionally explained using the rate of living theory, which suggests that higher temperatures increase chemical reaction rates, thus speeding up the aging process. However, recent studies have identified specific molecules, cells and signaling pathways involved in the longevity response to temperature, indicating that such a response is not simply thermodynamic but a regulated process. Here, we report that Caenorhabditis elegans lacking OCTR-1, a neuronal G protein-couple receptor for the neurotransmitter octopamine, had extended lifespan at warm temperature but shortened lifespan at cool temperature, indicating that OCTR-1 modulates the longevity response to both warm and cool temperatures. We further found that these responses are regulated by the OCTR-1-expressing, chemosensory ASH neurons. Transcriptomic analysis and functional assays revealed that OCTR-1 mediates temperature effects on longevity by regulating a subset of immune response genes. Our study provides cellular and molecular insights into the relationship between temperature and longevity, which could be useful for developing strategies to extend human lifespan in the midst of global warming.

immunology↗

The neuropeptide receptor NMUR-1 regulates the specificity of C. elegans innate immunity against pathogen infection

A key question in current immunology is how the innate immune system generates high levels of specificity. Using the Caenorhabditis elegans model system, we demonstrate that functional loss of NMUR-1, a neuronal G protein-coupled receptor homologous to mammalian receptors for the neuropeptide neuromedin U, has diverse effects on C. elegans innate immunity against various bacterial pathogens. Transcriptomic analyses and functional assays revealed that NMUR-1 modulates C. elegans transcription activity by regulating the expression of transcription factors involved in binding to RNA polymerase II regulatory regions, which, in turn, controls the expression of distinct immune genes in response to different pathogens. These results uncovered a molecular basis for the specificity of C. elegans innate immunity. Given the evolutionary conservation of NMUR-1 signaling in immune regulation across multicellular organisms, our study could provide mechanistic insights into understanding the specificity of innate immunity in other animals, including mammals.

microbiology↗

A novel in vitro Caenorhabditis elegans transcription system

Caenorhabditis elegans is an excellent model organism for biological research, but its contributions to biochemical elucidation of eukaryotic transcription mechanisms have been limited. One of the biggest obstacles for biochemical studies of C. elegans is the high difficulty of preparing functionally active nuclear extract due to its thick surrounding cuticle. By employing Balch homogenization, we have achieved effective disruption of larval and adult worms and have obtained functionally active nuclear extract through subcellular fractionation. In vitro transcription reactions were successfully re-constituted using such nuclear extract. Furthermore, two non-radioactive detection methods, PCR and qRT-PCR, have been adapted into our system to qualitatively and quantitatively detect transcription, respectively. Using this system to assess how pathogen infection affects C. elegans transcription revealed that Pseudomonas aeruginosa infection increased transcription activity. Our in vitro system is useful for biochemically studying C. elegans transcription mechanisms and gene expression regulations. The effective preparation of functionally active nuclear extract in our system fills a technical gap in biochemical studies of C. elegans and will expand the usefulness of this model organism in addressing many biological questions beyond transcription.

biochemistry↗