The complete sequence of the 16,569-base pair human mitochondrial genome is presented. The genes for the 12S and 16S rRNAs, 22 tRNAs, cytochrome c oxidase subunits I, II and III, ATPase subunit 6, cytochrome b and eight other predicted protein coding genes have been located. The sequence shows extreme economy in that the genes have none or only a few noncoding bases between them, and in many cases the termination codons are not coded in the DNA but are created post-transcriptionally by polyadenylation of the mRNAs.

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Although phytoalexins have long been inferred to be important in the defence of plants against fungal infection, there are few reports showing that they provide resistance to infection. Several plants, including grapevine, synthesize the stilbene-type phytoalexin resveratrol when attacked by pathogens. Stilbenes with fungicidal potential are formed in several unrelated plant species, such as peanut (Arachis hypogaea), grapevine (Vitis vinifera) and pine (Pinus sylvestris). Stilbene biosynthesis only specifically requires the presence of stilbene synthase. Furthermore, the precursor molecules for the formation of hydroxy-stilbenes are malonyl-CoA and p-coumaroyl-CoA, both present in plants. To investigate the potential of stilbene biosynthetic genes in a strategy of engineering pathogen resistance, we isolated stilbene synthase genes from grapevine, where they are expressed at a high level, and transferred them into tobacco. We report here that regenerated tobacco plants containing these genes are more resistant to infection by Botrytis cinerea. This is, to our knowledge, the first report of increased disease resistance in transgenic plants based on an additional foreign phytoalexin.

A hitherto largely unresolved problem in behavioral biology is how workers are prevented from reproducing in large insect societies with high relatedness. Signals of the queen are assumed to inform the nestmates about her presence in the colony, which leads to indirect fitness benefits for workers. In the ant Camponotus floridanus, we found such a signal located on queen-laid eggs. In groups of workers that were regularly provided with queen-laid eggs, larvae, and cocoons, with larvae and cocoons alone, or with no brood, only in the groups with queen-laid eggs did workers not lay eggs. Thus, the eggs seem to inform the nestmates about the queen's presence, which induces workers to refrain from reproducing. The signal on queen-laid eggs is presumably the same that enables workers to distinguish between queen-and worker-laid eggs. Despite their viability, the latter are destroyed by workers when given a choice between both types. Queen-and worker-laid eggs differ in their surface hydrocarbons in a way similar to the way fertile queens differ from workers in the composition of their cuticular hydrocarbons. When we transferred hydrocarbons from the queen cuticle to worker-laid eggs, the destruction of those eggs was significantly mitigated. We conclude that queen-derived hydrocarbon labels inform workers about the presence of a fertile queen and thereby regulate worker reproduction.

The formation of flavor in fermented beverages is due to various biosynthetic mechanisms. In wine, flavors arise as the result of compounds: 1. Originating from the native fruit (grap) 2. Which are formed or altered during the various processes employed in production 3. Which are developed or transformed by yeast during fermentation 4. Arise during the aging process In this review the results of investigations on the development of flavors in grape and wine will be discussed. Special attention will be devoted to the effects of specific processes in winemaking on the development of flavor.

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The nonstructural NSm protein of tomato spotted wilt tospovirus (TSWV) represents a putative viral movement protein involved in cell-to-cell movement of nonenveloped ribonucleocapsid structures. To study the molecular basis of NSm function, we expressed the protein in Escherichia coli and investigated protein-protein and protein-RNA interactions of NSm protein in vitro. NSm specifically interacts with TSWV N protein and binds single-stranded RNA in a sequence-nonspecific manner. Using NSm as a bait in a yeast two-hybrid screen, we identified two homologous NSm-binding proteins of the DnaJ family from Nicotiana tabacum and Arabidopsis thaliana.