As climate change begins to diminish yields for food crops such as rice and wheat, just how plants detect small changes in temperature has become a hot topic. To address this, S. Vinod Kumar and Philip Wigge at the John Innes Centre in Norwich, UK, increased the temperature in Arabidopsis thaliana seedlings from 12°C to 27°C and looked for plants that didn’t show the usual response to heat, such as flowering. A genetic screen of the anomalous plants revealed a mutation in ARP6, a gene that controls the insertion of the histone H2A.Z into nucleosomes, suggesting that ARP6 uses H2A.Z to release the genes that respond to warming.
Researchers had observed that the H2A.Z histone replaces the H2A histone in some nucleosomes, but “no one knew what the H2A.Z was doing,” in terms of temperature, says Wigge. In ARP6 gene mutants, the warm-temperature genes turn on in cool plants, suggesting H2A.Z critical role in the temperature response.
The paper is “a landmark in our understanding of plant temperature perception,” says F1000 Faculty Member Tapio Palva of the University of Helsinki in his review, and could have implications beyond the plant world. While temperature fluctuates far less in mammals, slight changes—such as those caused during fever—may still activate unique sets of genes. “People that work outside of plants have been picking up the paper and mentioning it,” says Wigge.
The authors plan to test whether H2A.Z is acting as a sensor for temperature change, which would be a first for histones.
F1000 evaluators: Y. M. Kong and X. W. Deng (Yale Univ) • S. Magori and V. Citovsky (SUNY at Stony Brook) • T. Palva (Univ. Helsinki) • D. Weigel (Max Planck Inst. Dev Biol) • D. Zheng (Einstein)