In early online publication, scientists found that in Arabidopsis thaliana, regions of DNA methylation are deficient in histone variant H2A.Z. Mutation of the MET1 DNA methyltransferase, which causes both losses and gains of DNA methylation, leads to opposite changes in H2A.Z deposition, whereas mutation of the PIE1 subunit of the Swr1 complex that deposits H2A.Z leads to genome-wide hypermethylation.
Several news features cover what the US presidential candidates have in mind for science and technology development if they hit office. One looks at their past accomplishments. In another Obama answered 18 science-related questions posed by Nature in writing; while McCain's campaign declined, his ideas are presented from previous speeches. Two more look at how the new president will choose the heads of the various science-related agencies and the presidential science advisor.
Bill Hahn led work that used loss-of-function screens to find that expression of CDK8 drives tumorigenesis in colon cancer. Rene Bernards pens a related News and Views that takes on how cross-talk between two pathways causes this dysregulation.
Finally, a Q&A checks in on metagenomics. From defining the field to addressing how it can be used to find genetic diversity, the Q&A clears things up for this sometimes nebulous "culture-independent, molecular way of analysing environmental samples of cohabiting microbial populations."