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From Genome to Life: Structural, Functional and Evolutionary Approaches Cargèse, Corsica July 15 - 26, 2002 Marc Fellous: Q: Why are there two sexes?. Inter-membrane space. I. II. III. IV. ATPase. Matrix. The mitochondrial theory of ageing Figure from:
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From Genome to Life: Structural, Functional and Evolutionary Approaches Cargèse, Corsica July 15 - 26, 2002 Marc Fellous: Q: Why are there two sexes?
Inter-membrane space I II III IV ATPase Matrix
The mitochondrial theory of ageing Figure from: ALLEN, J F (1996) J. Theor. Biol. 180, 135-140
Problem The Mitochondrial Theory of Ageing predicts that offspring should inherit their mother’s acquired state of accumulated damage, but they evidently do not. Babies are not born at the age of their mothers. How can this be?
Proposed solution (hypothesis) Separate sexes allows specialisation of mitochondria either as genetic templates (female germ line) oras energy-transducing organelles performing oxidative phosphorylation (male germ line) ALLEN, J F (1996) J. Theor. Biol. 180, 135-140
Predictions Explanations of previous knowledge Mitochondria are maternally inherited Females have a time-limited reproductive activity - oocyte mitochondria become useless as genetic templates after a certain threshold of oxidative damage is reached Oocyte mitochondria are energetically disabled - permanently. Experimental predictions Many…. E.g life-cycle of a germ-line mitochondrion Science and society Male and female are unequal but COMPLEMENTARY
From Genome to Life: Structural, Functional and Evolutionary Approaches Cargèse, Corsica July 15 - 26, 2002 Marc Fellous: Q: Why are there two sexes? John Allen: A: Division of labour to resolve the dilemma of mitochondria - energy convertion (male) OR fidelity of replication of mtDNA (female) http://plantcell.lu.se/john/pdf/96.pdf Vive la différence…….