Post on 19-Jan-2016
Affect of heavy metal induced oxidative stress tolerance on energy metabolism in Drosophila
melanogaster
Geetanjali SageenaEvolutionary Biology Laboratory
Department of Zoology University of Delhi New Delhi-110007
Industrialization and urbanization has resulted in environmental pollution.
Various Heavy metals are adding to environmental load due to higher rate of persistence and accumulation.
Results in oxidative stress. Persistent imbalance between antioxidants and pro-oxidants causing irreversible cellular damage.
Adaptive physiological mechanisms aid in increased survival which plays an important role in evolution and adaptation of living organisms.
Background
www.anatomy.unimelb.edu.au/.../life_cycle.jpg
22-24 h
~ 24 h
~ 24 h~ 48 h
~ 11
0 h
Fly maintenance
Pre Adult Duration 9½ days Lifespan 30 Days
Pre Adult Duration 7 days Lifespan 45 Days
Control• Resource Rich• Short Lifespan
Selected•Resource Deficient•Long Lifespan
Adult flies are housed in Plexiglas cages (25 x 20 x 15 cm3) Banana-jaggery food is provided in petridish and changed every alternate day. Populations kept at standard laboratory conditions (SLC).
To check the effect/affect of two chemical stressors (Heavy Metals) namely FeSO4 and CdCl2 on L1 to adult development.
Estimation of major energy reserves in both stressed and non stressed condition
Aims and Objectives
Two types of fly populations
Heavy Metal Conc.
MethodologyCONTROL (JBs)
SELECTED (FLJs)
SM
SM + 13 mM FeSO4
SM + 5µM CdCl2
1
2
3
4
YEAST
Sync Eggs
L1 to adult development time.Estimation of major energy reserves i.e. Lipids,
Proteins and Carbohydrates by Ether, BCA and Anthrone method respectively
Estimation of Energy accumulation per unit time.
(Platt and Irwin 1973)
RESULTSdevelopmental Time
Lipid content
PROTEIN content
carbohydrates content
energy accumulation/ time
Treatment F2,4 = 16.107, p = 0.01
Larval growth slowed when reared on heavy metal supplemented diet.
Increased development time did not result in the increased macromolecular accumulation among the flies. Slowing down of the metabolic processes, or a greater utilization of energy reserves during metamorphosis or both.
Bioenergetics play a crucial role in regulation of Oxidative stress. Positive relation between energy reserve and stress tolerance. Whereas
stress tolerance and lifespan are not tightly correlated.
Females more tolerant than males.
CONCLUSIONS
Acknowledgements My Supervisor Dr. Mallikarjun Shakarad
Funding agency CSIR &DU
Experimental Work: Mr. Rakesh Roshan
Ms Shreya Choudhary
Ms Nalini Mishra
Laboratory Assistance: Sahil Malhotra