Cellular localisation of VvRops and VvRabA5e, small GTPases developmentally regulated in grape berries

VvRops, in particular VvRop9, and VvRabA5e are small GTPases which are developmentally regulated in grape berries. In an attempt to help elucidate the role of these proteins during fruit development and ripening, we investigated their localisation in the fruit by immunocytofluorescence. These proteins were observed at a perinuclear location, at cell periphery and around vesicles. In particular VvRops were found to be located in the nucleus and likely on the plasma membrane. VvRop9 and VvRabA5e cDNAs were introduced separately into S. cerevisiae mutants with RHO1 and YPT31/YPT32 defective genes respectively. Neither cDNAs could complement these temperature-sensitive mutants, suggesting that the functions of the VvRop9 and VvRabA5e genes in grapevine likely differ from the functions of RHO1 and YPT31/YPT32 genes in yeast.

PA1b, a small knotted albumin from garden pea, protects transgenic rice against its major post-harvest insect pest Sitophilus oryzae

1-ACL (articles avec comité de lecture

Comparative Anatomy and Morphology of the Leaves of Grenache Noir and Syrah Grapevine Cultivars

International audienceGrenache Noir and Syrah are two of the grapevine (Vitis vinifera L.) cultivars used to a great extent worldwide. They have very different leaf morphologies from an ampelographic (botanical) point of view. This might also be related to differences in the anatomy and micro-morphology of their leaves. The goal of the present work was to compare these cultivar's leaf anatomy and morphology. Adult leaves from both cultivars were characterised using a range of microscopy techniques. Grenache Noir had a significantly smaller leaf surface area, but a significantly thicker leaf blade, than Syrah. It also had significantly larger stomata and a larger stomatal index than Syrah. The distribution of mesophyll tissues was similar in both cultivars, but the upper epidermis was significantly thicker in Grenache Noir, and the palisade parenchyma cells were longer in Syrah. The mesophyll tissues of both cultivars contained abundant idioblasts carrying crystals of calcium oxalate and mucilage. This work reveals quantitative and qualitative differences in the anatomy and morphology of mature Grenache Noir and Syrah leaves. Further work is needed to determine how these anatomical and morphological differences may be connected with different responses at the functional level