Improved allometric models to estimate the aboveground biomass of tropical trees

Terrestrial carbon stock mapping is important for the successful implementation of climate change mitigation policies. Its accuracy depends on the availability of reliable allometric models to infer oven‐dry aboveground biomass of trees from census data. The degree of uncertainty associated with previously published pantropical aboveground biomass allometries is large. We analyzed a global database of directly harvested trees at 58 sites, spanning a wide range of climatic conditions and vegetation types (4004 trees ≥ 5 cm trunk diameter). When trunk diameter, total tree height, and wood specific gravity were included in the aboveground biomass model as covariates, a single model was found to hold across tropical vegetation types, with no detectable effect of region or environmental factors. The mean percent bias and variance of this model was only slightly higher than that of locally fitted models. Wood specific gravity was an important predictor of aboveground biomass, especially when including a much broader range of vegetation types than previous studies. The generic tree diameter–height relationship depended linearly on a bioclimatic stress variable E, which compounds indices of temperature variability, precipitation variability, and drought intensity. For cases in which total tree height is unavailable for aboveground biomass estimation, a pantropical model incorporating wood density, trunk diameter, and the variable E outperformed previously published models without height. However, to minimize bias, the development of locally derived diameter–height relationships is advised whenever possible. Both new allometric models should contribute to improve the accuracy of biomass assessment protocols in tropical vegetation types, and to advancing our understanding of architectural and evolutionary constraints on woody plant development.     

Molecular phylogenetics of the gomphoid-phalloid fungi with an establishment of the new subclass Phallomycetidae and two new orders

Molecular phylogenetic analyses for the gomphoid-phalloid fungi were conducted based on the five gene dataset with extensive taxon sampling. The monophyly of the gomphoid-phalloid clade was strongly supported, and four well supported major subclades were recognized. Three of the four subclades were represented entirely by gastroid taxa, and only Gomphales contained both gastroid and non-gastroid taxa. While the gastroid morphology is derived from epigeous, nongastroid taxa in Gomphales, the topology of Phallales indicated that truffle-like form is an ancestral morphology of the stinkhorn fruiting bodies. Although basidiospore maturation occurs within the enclosed fruiting bodies of the stinkhorn, the elevation of the mature spore-producing tissue represents an independent origin of the stipe among Basidiomycota. Comparisons are made between previous and new classification schemes, which are based on the results of phylogenetic analyses. Based on the results of these analyses, a new subclass Phallomycetidae, and two new orders, Hysterangiales and Geastrales, are proposed.     

Control of IFN-alphaA by CD73: implications for mucosal inflammation

Inflammatory diseases influence tissue metabolism, altering regulation of extracellular adenine nucleotides, with a resultant protective influence of adenosine. Ecto-5'-nucleotidase (CD73) is a central surface enzyme generating extracellular adenosine. Thus, we hypothesized that CD73 is protective in mucosal inflammation as modeled by trinitrobenzene sulfonate (TNBS) colitis. Initial studies revealed a >3-fold induction of CD73 mRNA levels after TNBS colitis. Additionally, the severity of colitis was increased, as determined by weight loss and colonic shortening, in cd73(-/-) mice relative to cd73(+/+) controls. Likewise, enteral administration of the selective CD73 inhibitor alpha,beta-methylene ADP to cd73(+/+) mice resulted in a similar increase in severity of TNBS colitis. Gene array profiling of cytokine mRNA expression, verified by real-time PCR, revealed a >90% down-regulation of IFN-alphaA in cd73(-/-) mice and alpha,beta-methylene ADP-treated cd73(+/+) mice, compared with cd73(+/+) mice. Exogenous administration of recombinant IFN-alphaA partially protected TNBS-treated cd73(-/-) mice. Cytokine profiling revealed similar increases in both IFN-gamma and TNF-alpha mRNA in colitic animals, independent of genotype. However, IL-10 mRNA increased in wild-type mice on day 3 after TNBS administration, whereas cd73(-/-) mice mounted no IL-10 response. This IL-10 response was restored in the cd73(-/-) mice by exogenous IFN-alphaA. Further cytokine profiling revealed that this IL-10 induction is preceded by a transient IFN-alphaA induction on day 2 after TNBS exposure. Together, these studies indicate a critical regulatory role for CD73-modulated IFNalphaA in the acute inflammatory phase of TNBS colitis, thereby implicating IFN-alphaA as a protective element of adenosine signaling during mucosal inflammation.     

Combining conventional QTL analysis and whole-exome capture-based bulk-segregant analysis provides new genetic insights into tuber sprout elongation and dormancy release in a diploid potato population

Tuber dormancy and sprouting are commercially important potato traits as long-term tuber storage is necessary to ensure year-round availability. Premature dormancy release and sprout growth in tubers during storage can result in a significant deterioration in product quality. In addition, the main chemical sprout suppressant chlorpropham has been withdrawn in Europe, necessitating alternative approaches for controlling sprouting. Breeding potato cultivars with longer dormancy and slower sprout growth is a desirable goal, although this must be tempered by the needs of the seed potato industry, where dormancy break and sprout vigour are required for rapid emergence. We have performed a detailed genetic analysis of tuber sprout growth using a diploid potato population derived from two highly heterozygous parents. A dual approach employing conventional QTL analysis allied to a combined bulk-segregant analysis (BSA) using a novel potato whole-exome capture (WEC) platform was evaluated. Tubers were assessed for sprout growth in storage at six time-points over two consecutive growing seasons. Genetic analysis revealed the presence of main QTL on five chromosomes, several of which were consistent across two growing seasons. In addition, phenotypic bulks displaying extreme sprout growth phenotypes were subjected to WEC sequencing for performing BSA. The combined BSA and WEC approach corroborated QTL locations and served to narrow the associated genomic regions, while also identifying new QTL for further investigation. Overall, our findings reveal a very complex genetic architecture for tuber sprouting and sprout growth, which has implications both for potato and other root, bulb and tuber crops where long-term storage is essential.Subject terms: Genetic markers, Next-generation sequencing, Plant breeding, Agricultural genetics, Genetic mapping     

Colony sound facilitates sexual and agonistic activities in royal penguins

A unique playback system was used to exaggerate continuously the number of calls heard in royal penguin, Eudyptes schlegeli, colonies to determine whether social facilitation increases a female's exposure to both sexual and agonistic activities, a process that could influence the timing of reproduction in colonies. We also determined whether the source of colony sound or the phase of the breeding cycle influenced the facilitation of sexual or agonistic activities. The system recorded and then played a new 12-min colony sound sample every 24 min throughout the first four phases of the breeding cycle. Because each broadcast was unique, this playback system avoids the possibility of habituation and can modify the acoustic environment in social groups for extended periods of time. The activities of penguins in control colonies (with no playback) were compared with those in colonies that heard samples derived from either their own or a different colony. Colony sound facilitated both sexual and agonistic activities from male and female royal penguins during all four phases of the cycle that we examined. Playbacks from the perceiver's own colony facilitated a greater response than sound originating from a different colony. Studies comparing egg-laying dates in colonies exposed continuously to the sounds of agonistic activities with those in control colonies, or colonies exposed continuously to the sounds of sexual activities are now needed to determine whether the facilitation of agonistic activities opposes the effects of social stimulation on the hormonal changes leading to ovulation in colony-dwelling birds. Copyright 2000 The Association for the Study of Animal Behaviour.     

Protein expression profiling of endometrial malignancies reveals a new tumor marker: chaperonin 10

Endometrial carcinoma is a common malignancy in women, being exceeded in incidence only by that of breast, lung, and colorectal cancers. At present, no serum tumor markers are available for the monitoring of endometrial carcinoma patients, and patients with recurrent disease are detected only following the development of symptoms or abnormalities in imaging assessments. Similarly, no screening tools are available for endometrial carcinoma. Protein profiling by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) has proven to be a sensitive and fast method of analysis for small proteins or peptides to yield specific biomarkers. In this study, a variety of normal and malignant endometrial tissue samples were fractionated and analyzed by SELDI-TOF MS (SELDI is a version of MALDI utilizing protein "chips"). A number of proteins displayed differential expression in malignant endometrial tissues. One of the prominent proteins fractionated by weak cation exchange chromatography and displaying enhanced expression in these malignant tissues was identified as chaperonin 10. The increased expression of chaperonin 10 in malignant endometrial tissues was further confirmed by parallel Western blot and immunohistochemistry analyses.