Predicted impact of exotic vines on an endangered ecological community under future climate change

Potential interactions between climate change and exotic plant invasions may affect areas of high conservation value, such as land set aside for the protection of endangered species or ecological communities. We investigated this issue in eastern Australia using species distribution models for five exotic vines under climate regimes for 2020 and 2050. We examined how projected changes in the distribution of climatically suitable habitat may coincide with the remaining remnants of an endangered ecological community—littoral rainforests—in this region. The number of known infestations of each weed in tropical, subtropical and temperate areas was used to assess the likelihood of further expansion into areas projected to provide suitable habitat under future conditions. Littoral rainforest reserves were consistently predicted to provide bioclimatically suitable habitat for the five vines examined under both current and future climate scenarios. We explore the consequences and potential strategies for managing exotic plant invasions in these protected areas in the coming decades.     

Temporal and spatial differences in the emission of calls by pipistrelle bats<Emphasis Type="Italic">Pipistrellus pipistrellus</Emphasis> and<Emphasis Type="Italic">P. pygmaeus</Emphasis>

The number of orientation, feeding and social calls emitted by pipistrelle batsPipistrellus pipistrellus Schreber, 1774 andP. pygmaeus Leach, 1825 was recorded throughout the night at eight different sites. Social calls were unaffected by weather variables, whereas orientation calls and feeding buzzes were both significantly affected by cloud and temperature conditions. The number of emissions of each call type was significantly different between sites, indicating that the bats used different sites for different activities. Significant positive correlations between all three combinations of call types occurred only during the middle of the night, corresponding with the nadir of flying insects. This suggests that bats were engaged in activities other than feeding at this time, such as territory protection or mate attraction.     

Identification and functional analysis of NOL7 nuclear and nucleolar localization signals

Background  

NOL7 is a candidate tumor suppressor that localizes to a chromosomal region 6p23. This locus is frequently lost in a number of malignancies, and consistent loss of NOL7 through loss of heterozygosity and decreased mRNA and protein expression has been observed in tumors and cell lines. Reintroduction of NOL7 into cells resulted in significant suppression of in vivo tumor growth and modulation of the angiogenic phenotype. Further, NOL7 was observed to localize to the nucleus and nucleolus of cells. However, the mechanisms regulating its subcellular localization have not been elucidated.     

Separating the climatic signal from tree-ring width and maximum latewood density records

We propose a technique for separating the climatic signal which is contained in two tree-ring parameters widely used in dendroclimatology. The method is based on the removal of the relationship between tree-ring width (TRW) and maximum latewood density (MXD) observed for narrow tree rings from high latitudes. The new technique is tested on data from three larch stands located along the northern timberline in Eurasia. Correlations were calculated between the temperatures of pentads (five consecutive days), TRW chronologies and MXD chronologies calculated according to the standard and proposed methods. The analysis confirms the great importance of summer temperature for tree radial growth and tree-ring formation. TRW is positively correlated with the temperature of four to eight pentads (depending on the region) at the beginning of the growth season, but MXD as obtained by the standard technique is correlated with temperature over a much longer period. For maximum density series from which the relationship between MXD and TRW has been removed (MXD′), there is a clear correlation with temperatures in the second part of the growing season. These results are consistent with the known dynamics of tree-ring growth in high latitudes and mechanisms of tree-ring formation.     

Blocking of acidosis-mediated apoptosis by a reduction of lactate dehydrogenase activity through antisense mRNA expression.

Lactic acid produced from the cells is a potential cause of extra- and intracellular acidification. Due to scarce technical tools, lactic acid that leads to acidification could not be reduced and direct evidence of the relationship between metabolic lactate and apoptosis has not yet been elucidated. In this study, we designed a cellular pH regulation system in CHO cells by a reduction of lactate dehydrogenase (LDH) activity through LDH antisense mRNA expression. This inhibited lactate production and, therefore, acidification of the cytosol. Under HCO3(-)-buffered growth conditions, both the parent CHO cells and the engineered CHO cells maintained their extracellular pH and intracellular pH fairly well. However, upon acidification of the cytosol, only the parent CHO cells underwent apoptosis under HCO3(-)-free conditions. In fact, we observed a number of apoptosis-related events only in control cells, including mitochondrial dysfunction, cytochrome c release, and an increase in caspase-3 enzymatic activity.     

Origin of the cell nucleus,mitosis and sex: roles of intracellular coevolution

Background  

The transition from prokaryotes to eukaryotes was the most radical change in cell organisation since life began, with the largest ever burst of gene duplication and novelty. According to the coevolutionary theory of eukaryote origins, the fundamental innovations were the concerted origins of the endomembrane system and cytoskeleton, subsequently recruited to form the cell nucleus and coevolving mitotic apparatus, with numerous genetic eukaryotic novelties inevitable consequences of this compartmentation and novel DNA segregation mechanism. Physical and mutational mechanisms of origin of the nucleus are seldom considered beyond the long-standing assumption that it involved wrapping pre-existing endomembranes around chromatin. Discussions on the origin of sex typically overlook its association with protozoan entry into dormant walled cysts and the likely simultaneous coevolutionary, not sequential, origin of mitosis and meiosis.     

A Unified Rapid PCR Method for Detection of Normal and Expanded Trinucleotide Alleles of CAG Repeats in Huntington Chorea and CGG Repeats in Fragile X Syndrome

We report on a unified rapid betaine-based-PCR protocol for amplification of the (CAG)n region in Huntington disease (HD) and the (CGG)n region in Fragile X syndrome (FXS), followed by an electrophoretic separation on automated sequencer for precise determination of the triplet numbers. The high betaine concentration (2.5 M betaine) permits precise amplification of the CAG and CGG repeats. Ten HD affected patients and 10 healthy individuals from HD families were re-evaluated. For FXS the CGG region in normal individuals and premutations of about 100 repeats were precisely amplified by this protocol. Ten unrelated FXS premutation carriers and 24 mentally retarded non-FXS affected boys were re-examined by this method. The results totally coincided with the previous ones. This protocol is a good choice as a fast screening test. Within 24 h we can have preliminary information on the patient’s genetic status. Normal individuals, CGG premutation carriers up to 100 repeats, as well as HD patients carrying an expansion up to 50 CAG repeats can be easily clarified. This accounts for a relatively large proportion (about 90%) of the suspected HD and FXS patients, referred to our laboratory for genetic analysis. The calculation of the repeat’s number is more accurate for the correct interpretation of the results, screening tests and genetic counselling.