In the early, online version of the Proceedings of the National Academy of Sciences, an international team led by investigators in Australia and France report on loci linked to differences in flowering time and photoperiod in domestic legumes relative to their wild counterparts. Through quantitative trait locus analyses on wild and domestic pea and lentil lines, the team tracked down two sites in the genome with ties to photoperiod response. The alleles identified appear to allow for flowering during long days, enabling crop growth during summer months in parts of the world with chilly winters. "Our results identify the factor likely to have permitted the successful prehistoric expansion of legume cultivation to Northern Europe," INRA's Isabelle Lejeune-Hénaut, the study's senior author, and her colleagues write, "and define a conserved genetic basis for major adaptive changes in flowering phenology and growth habit in an important crop group."
A team from French Polynesia and France takes a look at the proteins behind biomineralization in parts of the pearl oyster shell. By using high-throughput approaches to assess gene expression and protein levels in multiple oyster tissues, the researchers found 80 proteins that make up the shell matrix in the Polynesian pearl oyster, Pinctada margaritifera, and the gold-lip oyster, P. maxima. Sixty-six of these shell matrix proteins have not been described previously, they report, expanding the 'biomineralization toolkit' involved in forming the so-called prism and nacre microstructures within pearl oyster shells. "We unambiguously demonstrate that prisms and nacre are assembled from very different protein repertoires," the team notes. "This suggests that these layers do not derive from each other."
Researchers from the Max Planck Institute for Developmental Biology's protein evolution department present a 'domain dictionary' approach for predicting the fiber structures of modular surface proteins contributing to host cell adhesion by pathogenic Gram-negative bacteria. The team used X-ray crystallography to garner structural information on trimeric autotransporter adhesin, or TAA, protein domains, which tend to share conserved structural features in enterobacteria, regardless of sequence level divergence. The domain dictionary approach proved useful for reconstructing fiber structures for TAA proteins from Salmonella enterica, enteropathogenic Eschericia coli, and uropathogenic E. coli, researchers report, noting that the study "completes the list of structural templates for frequently occurring TAA domains and proves both the robustness and the applicability of the dictionary approach to understanding TAA structure."