Thursday, March 18, 2010

Random bits #8

There are some interesting articles in this week's Nature. First, from the world of fungal genomics, Ma et al. report the genome sequences of two Fusarium species. Not surprisingly, each sequence has regions that are specific to the species it comes from, and those specific regions are also full of transposons. Regarding F. oxysporum, I found it amazing that its pathogenicity appears to be linked to a specific chromosome, which can apparently be transferred between strains. In one experiment, a nonpathogenic F. oxysporum strain that lacks the chromosome gained it by horizontal transfer, rendering the strain capable of infecting a host (in this case, tomato). Here I thought that kind of pathogenic gene transfer was a bacterial trick.

Ma et al. 2010. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium. Nature 464:367-373.

Speaking of genome sequences, a paper on the Hydra sequence by Chapman et al. was published in the Advanced Online papers. From the abstract:
The Hydra genome has been shaped by bursts of transposable element expansion, horizontal gene transfer, trans-splicing, and simplification of gene structure and gene content that parallel simplification of the Hydra life cycle. We also report the sequence of the genome of a novel bacterium stably associated with H. magnipapillata.
Sweet! A two-for-one deal.

Chapman et al. 2010. The dynamic genome of Hydra. Nature doi:10.1038/nature08830.

In other news, Brumm et al. report stone tools from Flores that push back the conventional date of H. floresiensis to at least 1 million years ago.

Brumm et al. 2010. Hominins on Flores, Indonesia, by one million years ago. Nature doi:10.1038/nature08844.

Just before dashing off to the train station yesterday, I had a chance to read Molén's letter in the most recent Journal of Creation, where he tried to respond to a blog post I wrote last summer. You might recall that I was disappointed with Molén's article on fossil equids and particularly his obsession with the polyphyly of Hyracotherium, and I tried to set the record straight on my blog. Molén's response made me sad. I don't think he understood what I wrote. Oh well. I tried. Further comment on Hyracotherium will have to await a proper analysis, whenever Paul Garner and I get around to finishing it.

Molén. 2010. The evolution of the horse. Journal of Creation 24(1):54-55.