A virus in a fungus in a plant: three-way symbiosis required for thermal tolerance

A mutualistic association between a fungal endophyte and a tropical panic grass allows both organisms to grow at high soil temperatures. We characterized a virus from this fungus that is involved in the mutualistic interaction. Fungal isolates cured of the virus are unable to confer heat tolerance, but heat tolerance is restored after the virus is reintroduced. The virus-infected fungus confers heat tolerance not only to its native monocot host but also to a eudicot host, which suggests that the underlying mechanism involves pathways conserved between these two groups of plants.     

The global circulation of seasonal influenza A (H3N2) viruses

Antigenic and genetic analysis of the hemagglutinin of approximately 13,000 human influenza A (H3N2) viruses from six continents during 2002-2007 revealed that there was continuous circulation in east and Southeast Asia (E-SE Asia) via a region-wide network of temporally overlapping epidemics and that epidemics in the temperate regions were seeded from this network each year. Seed strains generally first reached Oceania, North America, and Europe, and later South America. This evidence suggests that once A (H3N2) viruses leave E-SE Asia, they are unlikely to contribute to long-term viral evolution. If the trends observed during this period are an accurate representation of overall patterns of spread, then the antigenic characteristics of A (H3N2) viruses outside E-SE Asia may be forecast each year based on surveillance within E-SE Asia, with consequent improvements to vaccine strain selection.     

Cooperation, control, and concession in meerkat groups

"Limited control" models of reproductive skew in cooperative societies suggest that the frequency of breeding by subordinates is determined by the outcome of power struggles with dominants. In contrast, "optimal skew" models suggest that dominants have full control of subordinate reproduction and allow subordinates to breed only when this serves to retain subordinates' assistance with rearing dominants' own litters. The results of our 7-year field study of cooperative meerkats, Suricata suricatta, support the predictions of limited control models and provide no indication that dominant females grant reproductive concessions to subordinates to retain their assistance with future breeding attempts.     

Recent Recession of Tropical Cliffy Coasts: Elevated benches and other coastal forms give evidence of eustatic changes in sea level

My fieldwork in various parts of the world leads me to the conclusion that the retreat of cliffy coasts through abrasion and solutional erosion during Recent times has produced a whole complex of forms, including conspicuous benches well above sea level where bedrock conditions are favorable. In addition, flats of other origin are being developed at various levels. Broad exposures of beach rock are a marine phenomenon only in that such exposure is a result of beach recession and of the uncovering of materials that had been cemented, under freshwater conditions, along water tables, in some places 6 or more feet above sea level (24, 25). Contemporary coral and algal flats are forming in some instances several feet above the level of the highest tides.     

Synthetic Juvenile Hormone: Induction of Sex Pheromone Production in Ips confusus

Topical application of 25, 50, or 100 micrograms of 10,11-epoxy-farnesenic acid methyl ester in peanut oil induced male Ips confusus to produce sex pheromone in the hindgut Malpighian tubule region. Twenty-four hours aftertreatment of male beetles with 100 micrograms of hormone, their hindgut Malpighian tubule extract was more attractive to female beetles in a laboratory bioassay than was extract from males producing pheromone naturally in ponderosa pine logs.     

Renin and angiotensin: the complete system within the neuroblastoma x glioma cell

Cells of the homogeneous hybrid line neuroblastoma x glioma (NG108-15) have many neuronal properties. Immunocytochemical tests show that they contain both immunoreactive renin and angiotensin; direct radioimmunoassays show that they are positive for renin, angiotensin I, and angiotensin II; enzymatic assays show that they contain angiotensinogen and converting enzyme as well. The renin appears to be present in an enzymatically inactive form that can be activated by trypsin and then blocked by antiserum to purified mouse submaxillary renin. Renin concentration and activity are increased by enhancing cellular differentiation with dibutyryl cyclic adenosine monophosphate or by serum withdrawal. These findings demonstrate a complete renin-angiotensin system within these neuron-like cells, and suggest that activation of intracellular renin could generate angiotensin II.