Lysozyme-coated nanoparticles for active uptake and delivery of synthetic RNA and plasmid-encoded genes in plants.

Nanoparticle-mediated delivery of nucleic acids and proteins into intact plants has the potential to modify metabolic pathways and confer desirable traits in crops. Here we show that layered double hydroxide (LDH) nanosheets coated with lysozyme are actively taken up into the root tip, root hairs and lateral root junctions by endocytosis, and translocate via an active membrane trafficking pathway in plants. Lysozyme coating enhanced nanosheet uptake by (1) loosening the plant cell wall and (2) stimulating the expression of endocytosis and other membrane trafficking genes.

RNA-Based Control of Fungal Pathogens in Plants.

Our duty to conserve global natural ecosystems is increasingly in conflict with our need to feed an expanding population. The use of conventional pesticides not only damages the environment and vulnerable biodiversity but can also still fail to prevent crop losses of 20-40% due to pests and pathogens. There is a growing call for more ecologically sustainable pathogen control measures.

Miniature Inverted-Repeat Transposable Elements: Small DNA Transposons That Have Contributed to Plant Gene Evolution.

Angiosperms form the largest phylum within the Plantae kingdom and show remarkable genetic variation due to the considerable difference in the nuclear genome size of each species. Transposable elements (TEs), mobile DNA sequences that can amplify and change their chromosome position, account for much of the difference in nuclear genome size between individual angiosperm species. Considering the dramatic consequences of TE movement, including the complete loss of gene function, it is unsurprising that the angiosperms have developed elegant molecular strategies to control TE amplification and movement.

() Is Essential for Cell Proliferation and Cell Differentiation in Tomato.

Most flowering plant species contain at least two copies of the () gene with the encoded DEM proteins lacking homology to proteins of known biochemical function. In tomato (; ), stable mutations in the locus result in shoot and root meristem defects with the mutant failing to progress past the cotyledon stage of seedling development. Generation of a () transformant line in tomato allowed for the characterization of gene function past the seedling stage of vegetative development with plants displaying a range of leaf development abnormalities.

Clay nanoparticles efficiently deliver small interfering RNA to intact plant leaf cells.

RNA interference is triggered in plants by the exogenous application of double-stranded RNA or small interfering RNA (siRNA) to silence the expression of target genes. This approach can potentially provide insights into metabolic pathways and gene function and afford plant protection against viruses and other plant pathogens. However, the effective delivery of biomolecules such as siRNA into plant cells is difficult because of the unique barrier imposed by the plant cell wall.

DEFECTIVE EMBRYO AND MERISTEMS genes are required for cell division and gamete viability in Arabidopsis.

The DEFECTIVE EMBRYO AND MERISTEMS 1 (DEM1) gene encodes a protein of unknown biochemical function required for meristem formation and seedling development in tomato, but it was unclear whether DEM1's primary role was in cell division or alternatively, in defining the identity of meristematic cells. Genome sequence analysis indicates that flowering plants possess at least two DEM genes. Arabidopsis has two DEM genes, DEM1 and DEM2, which we show are expressed in developing embryos and meristems in a punctate pattern that is typical of genes involved in cell division.