Suppression of citrus canker disease mediated by flagellin perception.

Citrus cancer, caused by strains of Xanthomonas citri (Xc) and Xanthomonas aurantifolii (Xa), is one of the most economically important citrus diseases. Although our understanding of the molecular mechanisms underlying citrus canker development has advanced remarkably in recent years, exactly how citrus plants fight against these pathogens remains largely unclear. Using a Xa pathotype C strain that infects Mexican lime only and sweet oranges as a pathosystem to study the immune response triggered by this bacterium in these hosts, we herein report that the Xa flagellin C protein (XaFliC) acts as a potent defence elicitor in sweet oranges.

Role of the Citrus sinensis RNA deadenylase CsCAF1 in citrus canker resistance.

Poly(A) tail shortening is a critical step in messenger RNA (mRNA) decay and control of gene expression. The carbon catabolite repressor 4 (CCR4)-associated factor 1 (CAF1) component of the CCR4-NOT deadenylase complex plays an essential role in mRNA deadenylation in most eukaryotes. However, while CAF1 has been extensively investigated in yeast and animals, its role in plants remains largely unknown.

Structure-function relationship of a citrus salicylate methylesterase and role of salicylic acid in citrus canker resistance.

Salicylic acid (SA) and its methyl ester, methyl salicylate (MeSA) are well known inducers of local and systemic plant defense responses, respectively. MeSA is a major mediator of systemic acquired resistance (SAR) and its conversion back into SA is thought to be required for SAR. In many plant species, conversion of MeSA into SA is mediated by MeSA esterases of the SABP2 family.

Crystal Structure and Regulation of the Citrus Pol III Repressor MAF1 by Auxin and Phosphorylation.

MAF1 is the main RNA polymerase (Pol) III repressor that controls cell growth in eukaryotes. The Citrus ortholog, CsMAF1, was shown to restrict cell growth in citrus canker disease but its role in plant development and disease is still unclear. We solved the crystal structure of the globular core of CsMAF1, which reveals additional structural elements compared with the previously available structure of hMAF1, and explored the dynamics of its flexible regions not present in the structure.

From laboratory to field: OsNRAMP5-knockdown rice is a promising candidate for Cd phytoremediation in paddy fields.

Previously, we reported that OsNRAMP5 functions as a manganese, iron, and cadmium (Cd) transporter. The shoot Cd content in OsNRAMP5 RNAi plants was higher than that in wild-type (WT) plants, whereas the total Cd content (roots plus shoots) was lower. For efficient Cd phytoremediation, we produced OsNRAMP5 RNAi plants using the natural high Cd-accumulating cultivar Anjana Dhan (A5i).

The OsHMA2 transporter is involved in root-to-shoot translocation of Zn and Cd in rice.

Zinc (Zn) is an essential micronutrient for plants and humans. Cadmium (Cd) is a Zn analog and one of the most toxic heavy metals to humans. Here we investigated the role of the Zn/Cd transporter OsHMA2.

Characterizing the role of rice NRAMP5 in Manganese, Iron and Cadmium Transport.

Metals like manganese (Mn) and iron (Fe) are essential for metabolism, while cadmium (Cd) is toxic for virtually all living organisms. Understanding the transport of these metals is important for breeding better crops. We have identified that OsNRAMP5 contributes to Mn, Fe and Cd transport in rice.

Low cadmium (LCD), a novel gene related to cadmium tolerance and accumulation in rice.

The contamination of food crops by cadmium (Cd) is a major concern in food production because it can reduce crop yields and threaten human health. In this study, knockout rice plants (Oryza sativa) tagged with the gene trap vector pGA2707 were screened for Cd tolerance, and the tolerant line lcd was obtained. The lcd mutant showed tolerance to Cd on agar plates and in hydroponic culture during early plant development.

The OsNRAMP1 iron transporter is involved in Cd accumulation in rice.

Cadmium (Cd) is a heavy metal toxic to humans and the accumulation of Cd in the rice grain is a major agricultural problem, particularly in Asia. The role of the iron transporter OsNRAMP1 in Cd uptake and transport in rice was investigated here. An OsNRAMP1:GFP fusion protein was localized to the plasma membrane in onion epidermal cells.

The rice mitochondrial iron transporter is essential for plant growth.

In plants, iron (Fe) is essential for mitochondrial electron transport, heme, and Fe-Sulphur (Fe-S) cluster synthesis; however, plant mitochondrial Fe transporters have not been identified. Here we show, identify and characterize the rice mitochondrial Fe transporter (MIT). Based on a transfer DNA library screen, we identified a rice line showing symptoms of Fe deficiency while accumulating high shoot levels of Fe.

A rice phenolic efflux transporter is essential for solubilizing precipitated apoplasmic iron in the plant stele.

Iron deficiency is one of the major agricultural problems, as 30% of the arable land of the world is too alkaline for optimal crop production, rendering plants short of available iron despite its abundance. To take up apoplasmic precipitated iron, plants secrete phenolics such as protocatechuic acid (PCA) and caffeic acid. The molecular pathways and genes of iron uptake strategies are already characterized, whereas the molecular mechanisms of phenolics synthesis and secretion have not been clarified, and no phenolics efflux transporters have been identified in plants yet.

The mitochondrial genome of the phytopathogenic basidiomycete Moniliophthora perniciosa is 109 kb in size and contains a stable integrated plasmid.

We present here the sequence of the mitochondrial genome of the basidiomycete phytopathogenic hemibiotrophic fungus Moniliophthora perniciosa, causal agent of the Witches' Broom Disease in Theobroma cacao. The DNA is a circular molecule of 109,103 base pairs, with 31.9% GC, and is the largest sequenced so far.