https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Down-regulation of the cotton endo-1,4-β-glucanase gene KOR1 disrupts endosperm cellularization, delays embryo development, and reduces early seedling vigour https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27948 Gossypium hirsutum) endoglucanase, GhKOR1, plays significant roles in endosperm and embryo development. RNA interference (RNAi)- and co-suppression-mediated down-regulation of GhKOR1 resulted in smaller filial tissue and reduced seed weight, which were characterized by disrupted endosperm cellularization and delayed embryo development, leading to a delayed germination and a weak growth of seedlings early in development. The transgenic seeds exhibited fewer and smaller endosperm cells with irregular and brittle cell walls, and their embryos developed only to the globular stage at 10 days post-anthesis (DPA) when the wild-type endosperm has become highly cellularized and the embryo has progressed to the heart stage. The transgenic seed also displayed a significant reduction of callose in the seed coat transfer cells and reduced cellulose content both in the seed coat and in mature fibres. These findings demonstrate that GhKOR1 is required for the developmental of both seed filial and maternal tissues and the establishment of seedling vigour.]]> Wed 11 Apr 2018 17:07:07 AEST ]]> The soybean sugar transporter GmSWEET15 mediates sucrose export from endosperm to early embryo https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44256 Glycine max) seed is primarily composed of a mature embryo that provides a major source of protein and oil for humans and other animals. Early in development, the tiny embryos grow rapidly and acquire large quantities of sugars from the liquid endosperm of developing seeds. An insufficient supply of nutrients from the endosperm to the embryo results in severe seed abortion and yield reduction. Hence, an understanding of the molecular basis and regulation of assimilate partitioning involved in early embryo development is important for improving soybean seed yield and quality. Here, we used expression profiling analysis to show that two paralogous sugar transporter genes from the SWEET (Sugars Will Eventually be Exported Transporter) family, GmSWEET15a and GmSWEET15b, were highly expressed in developing soybean seeds. In situ hybridization and quantitative real-time PCR showed that both genes were mainly expressed in the endosperm at the cotyledon stage. GmSWEET15b showed both efflux and influx activities for sucrose in Xenopus oocytes. In Arabidopsis (Arabidopsis thaliana), knockout of three AtSWEET alleles is required to see a defective, but not lethal, embryo phenotype, whereas knockout of both GmSWEET15 genes in soybean caused retarded embryo development and endosperm persistence, resulting in severe seed abortion. In addition, the embryo sugar content of the soybean knockout mutants was greatly reduced. These results demonstrate that the plasma membrane sugar transporter, GmSWEET15, is essential for embryo development in soybean by mediating Suc export from the endosperm to the embryo early in seed development.]]> Tue 11 Oct 2022 12:42:46 AEDT ]]> Sugar loading of crop seeds - a partnership of phloem, plasmodesmal and membrane transport https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52099 Thu 28 Sep 2023 14:50:07 AEST ]]> Physiology of flowering and grain filling in faba bean https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:10704 Sat 24 Mar 2018 08:12:15 AEDT ]]> Cell wall invertase as a regulator in determining sequential development of endosperm and embryo through glucose signaling early in seed development https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:23715 Sat 24 Mar 2018 07:16:54 AEDT ]]>