Worm Breeder's Gazette 14(2): 34 (February 1, 1996)

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

Oxidative Stress and Aging in the daf Mutants

Shuji Honda, Yoko Honda

Tokyo Metropolitan Institute of Gerontology Tokyo 173 Japan, hondas@center.tmig.or.jp

    Dauer larva can survive for long periods in harsh environments. Some
of the daf genes that control dauer formation are expected to be  
involved in the acquisition of resistance to severe stress and  extention
of life span. We are interested in oxidative stress because oxidative 
stress is postulated to be one of the causative agents in  aging. In order

to clarify the mechanism of acquisition of stress resistance and 
extension of life span, the susceptibility to oxidative stress has been 
measured in various daf mutants and their double and triple mutants. In 
ts mutants, measurements were done at non-permissive temperatures 
after the L4 stage.
    daf-1 mutant, daf-3, daf-4, daf-5, daf-6, daf-7, daf-8, daf-10, 
daf-12, daf-13, daf-14, daf-16, daf-18, daf-19 and daf-22 are similar 
to wild type N2 with respect to susceptibility to oxidative stress. 
    daf-2(e1370) and daf-2(e1286) are more resistant to oxidative 
stress than N2. On the other hand daf-2(m41) and daf-2(e1368) were 
similar to N2.
    daf-23(m333) are more resistant to oxidative stress than N2.
    daf-2(e1370); daf-3(e1376)  double mutant and daf-5(e1386); daf-2 
(e1370) are similar to daf-2(e1370). 
    daf-16(m26); daf-2(e1370) and daf-18(e1375); daf-2(e1370) are 
similar to N2.
    daf-2(e1370); daf-12(m20) is somewhat more resistant than daf-2 
    daf-16(m26); daf-2(e1370); daf-12(m20)  triple mutant is similar 
to N2.
    daf-16(m26); daf-23(m333) is similar to N2. daf-18(e1375); daf-23
(m333) is intermediate between daf-18 and daf-23 .
     We have measured the adult life span of long-life mutants: daf-2 
and daf-2; daf-12 under hyperoxia. N2 life span under hyperoxia was 
about 70% of that under an air atmosphere. By contrast, the life span 
of daf-2(e1370) under hyperoxia was about 90% of that under air 
atmosphere, and the life span of daf-2(e1370); daf-12(m20) was 
almost the same as that under air atmosphere, indicating correlation 
between oxidative-stress resistance and longevity.
     These results indicate that the characteristic genetic pathway 
involved in acquiring oxidative-stress tolerance is similar to that 
involved in determining longevity (Larsen et al., '95).

    daf-2 - daf-18 - daf-23 - daf-16 -   (oxidative-stress resistance)   

References: S.Honda et al., Mech. Age. Devel. 63 235 '92, J. Gerontol. 48 
B57 '93, C. Kenyon et al., Nature 366 461 '94, P. L. Larsen et al.,
139 1567 '95
Acknowledgement: We thank Dr. Don L. Riddle, MRC and CGC for strains.