GDP-Mannose 3',5'-epimerase (GME; EC 5.1.3.18) catalyses the conversion of GDP-D-mannose to GDP-L-galactose, an important step in the ascorbic acid (AsA) biosynthesis pathway in higher plants. In this study, two members of the GME gene family were isolated from tomato (Solanum lycopersicum). Both SlGME genes encode 376 amino acids and share a 92% similarity with each other. Semi-quantitative RT-PCR indicated that SlGME1 was constantly expressed in various tissues, whereas SlGME2 was differentially expressed in different tissues. Transient expression of fused SlGME1-GFP (green fluorescent protein) and SlGME2-GFP in onion cells revealed the cytoplasmic localisation of the two proteins. Transgenic plants over-expressing SlGME1 and SlGME2 exhibited a significant increase in total ascorbic acid in leaves and red fruits compared with wild-type plants. They also showed enhanced stress tolerance based on less chlorophyll content loss and membrane-lipid peroxidation under methyl viologen (paraquat) stress, higher survival rate under cold stress, and significantly higher seed germination rate, fresh weight, and root length under salt stress. The present study demonstrates that the overexpression of two members of the GME gene family resulted in increased ascorbate accumulation in tomato and improved tolerance to abiotic stresses.

5-Hydroxymethylfurfural (HMF) was converted to maleic anhydride in 52% yield via selective oxidation with molecular oxygen using VO(acac) 2 as catalyst in liquid phase.Maleic anhydride (MA) is a versatile chemical intermediate used to produce a variety of products such as unsaturated polyester resins, 1,4-butanediol, fumaric acid, and tetrahydrofuran.

SummaryLong noncoding RNAs (lncRNAs) have several known functions in plant development, but their possible roles in responding to plant disease remain largely unresolved. In this study, we described a comprehensive disease‐responding lncRNA profiles in defence against a cotton fungal disease Verticillium dahliae. We further revealed the conserved and specific characters of disease‐responding process between two cotton species. Conservatively for two cotton species, we found the expression dominance of induced lncRNAs in the Dt subgenome, indicating a biased induction pattern in the co‐existing subgenomes of allotetraploid cotton. Comparative analysis of lncRNA expression and their proposed functions in resistant Gossypium barbadense cv. ‘7124’ versus susceptible Gossypium hirsutum cv. ‘YZ1’ revealed their distinct disease response mechanisms. Species‐specific (LS) lncRNAs containing more SNPs displayed a fiercer inducing level postinfection than the species‐conserved (core) lncRNAs. Gene Ontology enrichment of LS lncRNAs and core lncRNAs indicates distinct roles in the process of biotic stimulus. Further functional analysis showed that two core lncRNAs, GhlncNAT‐ANX2‐ and GhlncNAT‐RLP7‐silenced seedlings, displayed an enhanced resistance towards V. dahliae and Botrytis cinerea, possibly associated with the increased expression of LOX1 and LOX2. This study represents the first characterization of lncRNAs involved in resistance to fungal disease and provides new clues to elucidate cotton disease response mechanism.