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SummaryHeme activator protein (HAP), also known as nuclear factor Y or CCAAT binding factor (HAP/NF-Y/CBF), has important functions in regulating plant growth, development and stress responses. The expression of rice HAP gene (OsHAP2E) was induced by probenazole (PBZ), a chemical inducer of disease resistance. To characterize the gene, the chimeric gene (OsHAP2E::GUS) engineered to carry the structural gene encoding b-glucuronidase (GUS) driven by the promoter from OsHAP2E was introduced into rice. The transgenic lines of OsHAP2Ein::GUS with the intron showed high GUS activity in the wounds and surrounding tissues. When treated by salicylic acid (SA), isonicotinic acid (INA), abscisic acid (ABA) and hydrogen peroxide (H 2 O 2 ), the lines showed GUS activity exclusively in vascular tissues and mesophyll cells. This activity was enhanced after inoculation with Magnaporthe oryzae or Xanthomonas oryzae pv. oryzae. The OsHAP2E expression level was also induced after inoculation of rice with M. oryzae and X. oryzae pv. oryzae and after treatment with SA, INA, ABA and H 2 O 2, respectively. We further produced transgenic rice overexpressing OsHAP2E. These lines conferred resistance to M. oryzae or X. oryzae pv. oryzae and to salinity and drought. Furthermore, they showed a higher photosynthetic rate and an increased number of tillers. Microarray analysis showed up-regulation of defence-related genes. These results suggest that this gene could contribute to conferring biotic and abiotic resistances and increasing photosynthesis and tiller numbers.

The chestnut blight fungus, Cryphonectria parasitica, is an important plant pathogenic ascomycete. The fungus hosts a wide range of viruses and now has been established as a model filamentous fungus for studying virus/host and virus/virus interactions. This is based on the development of methods for artificial virus introduction and elimination, host genome manipulability, available host genome sequence with annotations, host mutant strains, and molecular tools. Molecular tools include sub-cellular distribution markers, gene expression reporters, and vectors with regulatable promoters that have been long available for unicellular organisms, cultured cells, individuals of animals and plants, and certain filamentous fungi. A comparison with other filamentous fungi such as Neurospora crassa has been made to establish clear advantages and disadvantages of C. parasitica as a virus host. In addition, a few recent studies on RNA silencing vs. viruses in this fungus are introduced.

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An unprecedented photocatalytic system consisting of benzimidazolium aryloxide betaines (BI+–ArO–) and stoichiometric hydride reducing reagents was developed for carrying out desulfonylation reactions of N-sulfonyl-indoles, -amides, and -amines, and α-sulfonyl ketones. Measurements of absorption spectra and cyclic voltammograms as well as density functional theory (DFT) calculations were carried out to gain mechanistic information. In the catalytic system, visible-light-activated benzimidazoline aryloxides (BIH–ArO–), generated in situ by hydride reduction of the corresponding betaines BI+–ArO–, donate both an electron and a hydrogen atom to the substrates. A modified protocol was also developed so that a catalytic quantity of more easily prepared hydroxyaryl benzimidazolines (BIH–ArOH) is used along with a stoichiometric hydride donor to promote the photochemical desulfonylation reactions.

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Pyridines and 2,2'-bipyridines have been employed as useful ligands in molecular recognition chemistries. Halomethyl-substituted bipyridine or oligopyridine derivatives were required for the assembly of bipyridine or oligopyridine units with a supporting mother functional part in artificial biofunctional molecules. A series of w4bromomethyl)bipyridines and related w-(bromomethy1)pyridinoheteroaromatic compounds (types 1-111) were synthesized in this paper. Preparation of oligopyridines and pyridinoheteroaromatic compounds have been carried out by either intermolecular ligand coupling of alkyl heteroaryl sulfoxide with pyridyllithium or intramolecular ligand coupling of pyridyl heteroaryl sulfoxide with methylmagnesium bromide for the type I compounds. The type I1 and I11 compounds were synthesized by addition of pyridyllithium to pyridinecarboxaldehyde. The w-bromo group was introduced by radical bromination reaction of methylpyridyl group using NBS and BPO (dibenzoyl peroxide) or bromination of w-(hydroxymethy1)pyridine using a combination of CBr4 and PhaP.

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