In an advance online publication of Science this week, researchers at the University of Pennsylvania Medical School and their colleagues show that AMP-activated protein kinase — AMPK — "activates stress-promoted transcription via histone H2B phosphorylation." They show that "AMPK recruitment and H2B S36 phosphorylation co-localize within genes activated by AMPK-dependent pathways, and occur both in promoters and transcribed regions." AMPK-dependent H2B S36 phosphorylation, the authors write, is a component of a "transcriptional and chromatin regulatory pathway leading to cellular adaptation to stress."
Researchers in Japan and France this week report that "peptides of 11 to 32 amino acids encoded by the polished rice (pri) sORF gene control epidermal differentiation in Drosophila by modifying the transcription factor Shavenbaby" — or Svb. These pri peptides, the team shows, "trigger the amino-terminal truncation of the Svb protein," converting the transcription factor from a repressor to an activator. The team suggests that Pri sORF peptides "provide a strict temporal control to the transcriptional program of epidermal morphogenesis."
Investigators at the University of Lausanne, Switzerland, and Stanford University suggest that "chromosome size differences may affect meiosis and genome size." Specifically, John Wang et al. found that chromosomes with insertions "preferentially segregated away from the X chromosome during meiosis in Caenorhabditis elegans males," and that the "degree of segregation bias was significantly associated with the length of the insertion or deletion."
And in Science Signaling, a Weizmann Institute of Science-led team reports their use of phosphoproteomics and microarrays to deduce signaling pathways to transcription networks in the neuronal retrograde injury response. Their computational analyses identified about "400 redundant axonal signaling networks connected by 39 transcription factors implicated in the sensory neuron response to axonal injury." The team suggests that "network redundancies provide robustness to the injury response."