Mutations in Chemosensory Cilia Cause Resistance to Paraquat in Nematode Caenorhabditis elegans*
- Michihiko Fujii‡,
- Yuki Matsumoto‡,
- Nanae Tanaka‡,
- Kensuke Miki‡,
- Toshikazu Suzuki‡,
- Naoaki Ishii§ and
- Dai Ayusawa‡¶
- ‡Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Totsuka-ku, Yokohama 244-0813, Japan and the §Department of Molecular Biology, Tokai University School of Medicine, Bosedai, Isehara, Kanagawa, 259-1193, Japan
- ¶ To whom correspondence should be addressed. Tel.: 81-45-820-1906; Fax: 81-45-820-1901; E-mail: dayusawa{at}yokohama-cu.ac.jp.
Abstract
The relationship between oxidative stress and longevity is a matter of concern in various organisms. We isolated mutants resistant to paraquat from nematode Caenorhabditis elegans. One mutant named mev-4 was long-lived and showed cross-resistance to heat and Dyf phenotype (defective in dye filling). Genetic and sequence analysis revealed that mev-4 had a nonsense mutation on the che-11 gene, homologues of which are involved in formation of cilia and flagella in other organisms. The paraquat resistance was commonly observed in various Dyf mutants and did not depend on the daf-16 gene, whereas the extension of life span did depend on it. Expression of antioxidant enzyme genes seemed normal. These results suggest that chemosensory neurons are a target of oxidative stress and influence longevity dependent on the daf-16 signaling in C. elegans.
Footnotes
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↵1 The abbreviations used are: ROS, reactive oxygen species; SOD, superoxide dismutase; FITC, fluorescein isothiocyanate; IFT, intraflagellar transport.
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↵2 M. Fujii, Y. Matsumoto, and D. Ayusawa, unpublished results.
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↵* This work was supported by The Japan Science Society Fund and grants-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
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- Received December 2, 2003.
- Revision received February 18, 2004.
- The American Society for Biochemistry and Molecular Biology, Inc.
