As many know, I generally do not write a lot about papers in non open access journal because I like readers to be able to access all the papers which I write about. But this is one of the exceptions to my normal rule. An amazing paper was published a few days ago in Science by Nancy Moran and Tyler Jarvik. Lateral Transfer of Genes from Fungi Underlies Carotenoid Production in Aphids -- Moran and Jarvik 328 (5978): 624 -- Science
I first found out about this from Ed Yong's blog post here (just a note - his Not Exactly Rocket Science is such a frigging incredible blog). He really does the whole story on this so I am just posting a bit here.
Anyway Moran and Jarkiv paper focuses on genes in the aphid genome that encode enzymes for carotenoid synthesis. These enzymes are involved in red and/or green coloring seen in the pea aphids. Recently the pea aphid genome was sequenced (a paper about this was published in PLoS Biology ) and it was analysis of the genome data that helped lead Moran and Jarvik to the study reported in the recent issue of Science.
In their study they report a detailed evolutionary and phylogenetic analysis of the carotenoid synthesis genes found in the aphid genome and show quite convincingly that these genes do not appear to be of "normal" descent. That is, they seem to have an ancestry separate from many of the "normal" animal genes in the genome. Instead, these genes are related to genes from fungi. In fact, these genes are embedded in an evolutionary sense, in a group of genes which are all from fungi and thus Moran and Jarvik conclude the most likely explanation is that some time in relatively recent pea aphid evolutionary history, these genes were acquired from some fungus.
About to have some eye drops put in my eyes so gotta go for now, but just wanted to get something out there about this fascinating work. For more on this story - there is lots out there, such as the following:
- Aphid's Color Comes From a Fungus Gene
- Aphids Pilfered Red Genes from Fungus
- Pea Aphids Create Their Own Coloring, Study Reveals
- Insect stole fungus gene to make plant pigment
- Animals Can Get Genes From Other Species: Research
- Aphids evolved special, surprising talents
- 1 st pigment-making animal found
- Aphids make their own bright colors
Moran, N., & Jarvik, T. (2010). Lateral Transfer of Genes from Fungi Underlies Carotenoid Production in Aphids Science, 328 (5978), 624-627 DOI: 10.1126/science.1187113
. (2010). Genome Sequence of the Pea Aphid Acyrthosiphon pisum PLoS Biology, 8 (2) DOI: 10.1371/journal.pbio.1000313
We're doing this for journal club on Thursday and we're looking forward to a good discussion on lateral gene transfer. BTW, we did your PLoS One paper on similated metagenomics last week.ReplyDelete
I am going to discuss this paper in class on Thursday too -- will try to post some stuff online about itReplyDelete
Hope the discussion of the metasim paper went OK.
That's quite an amazing story! And I'm wondering if the transfer could have gone both ways between fungi and insects - I still remember being rather confused by finding several fungal genes in a microarray study that only shared sequence homology with insects and no other fungi at all. Now they look slightly less ridiculous ;)ReplyDelete