Friday, April 30, 2010

This week in Science

Anyone else tired of Noah's Ark? Great, then I have some really interesting articles in the latest Science we can read instead. First, the Xenopus tropicalis genome has been published. Results are pretty much as expected: 20,000 predicted genes in a 1.7 Gb genome (ten chromosomes). A third is transposable element, and it shares a great deal of conserved synteny with the chromosomes of other vertebrates (notably chicken and human).

Hellsten et al. 2010. The Genome of the Western Clawed Frog Xenopus tropicalis. Science 328:633-636.

Also interesting in the genome-sequencing department is the report of the complete genomes of a human family of four (two parents, two children). The research team directly estimated the mutation rate as 1.1 x 10-8. That should be a useful piece of knowledge.

Roach et al. 2010. Analysis of Genetic Inheritance in a Family Quartet by Whole-Genome Sequencing. Science 328:636-639.

Edwards et al. have an interesting review on the origin of C4 grasslands, which is a topic I find quite interesting. They argue that the origin is more complicated than previously believed (no surprise there), and they call for a better synthesis with grass phylogenetics.

Edwards et al. 2010. The Origins of C4 Grasslands: Integrating Evolutionary and Ecosystem Science Science 328:587-591.

And finally, an animal makes its own carotenoids! Moran and Jarvik report on aphid genes for carotenoid synthesis that were initially derived from "fungal genes, which have been integrated into the genome and duplicated." Red aphids have a mutant enzyme which makes red carotenoids, where green ones do not. Amazing.

Moran and Jarvik. 2010. Lateral Transfer of Genes from Fungi Underlies Carotenoid Production in Aphids. Science 328:624-627.