Altmann’s Bioblasts - The four seasons ( Credit: Odra Noel )
Why are there two sexes? It's a question that has long perplexed generations of scientists, but researchers from UCL have come up with a radical new answer: mitochondria. Using a new mathematical model, the team led by Nick Lane and colleagues from the UCL CoMPLEX, and the Research Department of Genetics, Evolution and Environment showed that inheriting mitochondria from only one parent - in effect, the 'female' - improves fitness by optimizing the interactions between the two genomes. The paper is published today in Proceedings of the Royal Society B . Lane said: "The difference between the sexes boils down to the need to keep fit when energy demands are high". Descended from free-living bacteria, mitochondria were swallowed whole by another cell between one and a half to two billion years ago. But despite being engulfed, these tiny power packs have retained their own tiny genome, encoding just a handful of proteins, all of which are necessary for generating energy in the cell. The strangest thing about this odd arrangement is that cell respiration relies on proteins encoded by two genomes, the tiny mitochondrial genome and the nucleus, where most DNA is stored.
TO READ THIS ARTICLE, CREATE YOUR ACCOUNT
And extend your reading, free of charge and with no commitment.
