Antioxidant responses of the pest natural enemy Hylyphantes graminicola (Araneae: Linyphiidae) exposed to short-term heat stress

Temperature is a critical abiotic factor that causes physiological changes in arthropods. However, little is known about the effect of heat stress on the antioxidant responses of Araneae species. Hylyphantes graminicola is a dominant predator in many cropping systems in China. In the present study, the effect of short-term heat stress (36, 38, 40 or 42 °C) on the reactive oxygen species (ROS) levels, the activities of antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], peroxidases [POD] and glutathione-S-transferases GST]), total antioxidant capacity (TAC), malondialdehyde (MDA) concentrations and survival of H. graminicola spiderlings and adults were investigated. The results showed that H. graminicola adults had a significantly higher survival rate compared to spiderlings at 40 °C. The heat stress increased ROS contents in H. graminicola. The SOD, CAT, POD and GST activities increased in spiderlings and adults under heat stress. These data suggest a defensive function for these enzymes in alleviating oxidative damage. Specifically, SOD plays a key role in reducing the high level of superoxide radicals in spiderlings and adults. Moreover, the POD and CAT capabilities for scavenging H₂O₂ in spiderlings were similar, and CAT may play a more important role than POD in scavenging H₂O₂ in adults at 42 °C. The spiderling TAC increased significantly at 40 and 42 °C, and the adult TAC was stable at 36–40 °C but decreased at 42 °C. These data suggest that TAC was insufficient in H. graminicola adults under more severe stress conditions. These results further our understanding of the physiological response of Araneae species exposed to heat stress.     

Effect of heat stress on superoxide anion production in native and crossbred cattle under in vitro whole blood culture model

Impact of global warming on the dairy industry has gained attention due to huge economic losses through low production and fertility caused by heat stress. Exposure to hyperthermia provokes a series of complex responses in mammals which are been related to morphological and physiological alterations including the production of reactive oxygen species (ROS). A quantitative spectrophotometric based nitroblue tetrazolium (NBT) reduction assay was used to estimate the superoxide anion (•O₂⁻) level in heat stressed (at 42 °C) whole blood cultures of native and crossbred bulls (Sahiwal and Frieswal), in vitro. The breed effect in the kinetics of •O₂⁻ production at different time periods of continual heat stress was analyzed by repeated measures ANOVA. Comparison between different time periods in reference to 37 °C was analyzed by paired t-test. The •O₂⁻ level was significantly different (p < 0.05) between cells at 37 °C and 42 °C at different periods of incubation. Kinetics study showed increment of •O₂⁻ production on the acute phase of stress followed by a reduction in both Sahiwal and Frieswal breeds. In Sahiwal breed, the inflated superoxide level continued abated till 4 h and raised again at 6 h, while in Frieswal •O₂⁻ level reverted to raise sooner with in 2 h of incubation itself. Contrarily, kinetic of •O₂⁻ level in plasma showed a significant reduction (p < 0.001) at 30 min of 42 °C incubation followed by increment of •O₂⁻ level. Further, the breed variation was significant (p < 0.05) and a significant high reduction of •O₂⁻ level was observed in Sahiwal breed. Our finding indicates that, a better and longer •O₂⁻ production homeostasis and higher plasma scavenging ability of native breed may be one of the reasons for the higher thermal tolerance of these breeds in tropical climate.     

Recombinant small heat shock protein from <Emphasis Type="Italic">Acholeplasma laidlawii</Emphasis> increases the <Emphasis Type="Italic">Escherichia coli</Emphasis> viability in thermal stress by selective protein rescue

In both prokaryotes and eukaryotes, the survival at temperatures considerably exceeding the optimum is supported by intense synthesis of the so-called heat shock proteins (HSPs), which act to overcome the adverse effects of heat stress. Among mycoplasmas (class Mollicutes), which have significantly reduced genomes, only some members of the Acholeplasmataceae family possess small HSPs of the α-crystallin type. Overproduction of a recombinant HSP IbpA (Hsp20) from the free-living mycoplasma Acholeplasma laidlawii was shown to increase the resistance of Escherichia coli to short-term heat shock. It has been long assumed that IbpA prevents protein aggregation and precipitation thereby increasing viability of E. coli cells. Several potential target proteins interacting with IbpA under heat stress were identified, including biosynthetic enzymes, enzymes of energy metabolism, and components of the protein synthesis machinery. Statistical analysis of physicochemical properties indicated that IbpA interaction partners significantly differ in molecular weight, charge, and isoelectric point from other members of the E. coli proteome. Upon shortterm exposure to increased temperature, IbpA was found to preferentially interact with high-molecularweight proteins having a pI of about 5.1, significantly lower than the typical values of E. coli proteins.     

The identification and characterization of IbpA,a novel α-crystallin-type heat shock protein from mycoplasma

α-Crystallin-type small heat shock proteins (sHsps) are expressed in many bacteria, animals, plants, and archaea. Among mycoplasmas (Mollicutes), predicted sHsp homologues so far were found only in the Acholeplasmataceae family. In this report, we describe the cloning and functional characterization of a novel sHsp orthologue, IbpA protein, present in Acholeplasma laidlawii. Importantly, similar to the endogenously expressed sHsp proteins, the recombinant IbpA protein was able to spontaneously generate oligomers in vitro and to rescue chemically denatured bovine insulin from irreversible denaturation and aggregation. Collectively, these data suggest that IbpA is a bona fide member of the sHsps family. The immune-electron microscopy data using specific antibodies against IbpA have revealed different intracellular localization of this protein in A. laidlawii cells upon heat shock, which suggests that IbpA not only may participate in the stabilization of individual polypeptides, but may also play a protective role in the maintenance of various cellular structures upon temperature stress.     

Comparison of thermotolerance of sun-exposed peel and shaded peel of ‘Fuji’ apple

The thermotolerance of the sun-exposed peel and the shaded peel of ‘Fuji’ apple (Malus domestica Borkh.) fruit was evaluated by measuring pigments, chlorophyll a fluorescence transients and O₂ evolution or uptake after exposure to 25, 35, 40, 42, 44, 46 or 48 °C for 30 min in the dark. A major effect of heat stress at 46–48 °C on the chlorophyll a fluorescence transients was the appearance of a very clear K step at 200–300 μs for both peel types. The K step was slightly more pronounced in the sun-exposed peel than in the shaded peel, suggesting that the resistance of oxygen-evolving complex to heat stress is slightly lower in the sun-exposed peel than in the shaded peel. Minimal fluorescence (F_O), relative to the value at 25 °C, increased to a greater extent in the shaded peel than in the sun-exposed peel after exposure to 46–48 °C, but the temperature dependencies of F_O changes were similar for both peel types. Maximum quantum yield of PSII (F_V/F_M) decreased to a similar extent in the sun-exposed peel and the shaded peel as temperature rose from 25 to 44 °C, but the sun-exposed peel reached slightly lower values at 46–48 °C. Correspondingly, gross O₂ evolution rate, relative to that at 25 °C, was also slightly lower in the sun-exposed peel than in the shaded peel at 46–48 °C. In response to heat stress, the ratio of Q_A-reducing reaction centers (RCs) to total RCs and the ratio of Q_B-reducing RCs to Q_A-reducing RCs decreased, but both of them decreased to lower values in the sun-exposed peel than in the shaded peel at 46–48 °C, indicating that the capacity of electron transfer between P₆₈₀⁺ and Q_B via Q_A was damaged to a greater extent in the sun-exposed peel than in the shaded peel. At each given temperature, dark respiration was similar between the two peel types. Overall, it appears that the exposure to higher surface temperature under high light does not make the sun-exposed peel more tolerant of heat stress than the shaded peel of apple fruit.     

Modeling analysis on sporulation capacity,storage and infectivity of the aphid-specific pathogen Conidiobolus obscurus (Entomophthoromycota: Entomophthorales)

Entomophthorales are important natural enemies against agroforestry pests. Conidiobolus obscurus in this order, a common obligate aphid pathogen, possesses features of rapid growth in vitro and ease to mass production. This study sought to evaluate the potential of C. obscurus in aphid biocontrol, by modeling analyzing on the sporulation capacity and storage of its alginate formulation and infectivity to Myzus persicae. The C. obscurus mycelia-entrapping alginate pellets discharges 0.12–18.26 × 10⁴ conidia per pellet at 4−32 °C. The optimal temperature for the fungal sporulation was computed as 23.3 °C. Each pellet could sporulated for 7 d, releasing 22.3-fold more conidia than a cadaver at 24 °C. Moreover, it had longevity of 8 mo at 4 °C, with half decline time of 2.3 mo. The infectivity of C. obscurus was assessed by multi-concentration bioassays at 10−28 °C and 8−16 h light per d. The median lethal concentration (LC₅₀) at each temperature-photoperiod regime was computed based on the morality-concentration trend. The LC₅₀ values reached the lowest one of 15 conidia per mm² at 28 °C and 16:8 L:D cycles. The total results suggest that C. obscurus mycelia-inclusive alginate pellets meet the requirement of aphid biocontrol in the high-temperature surroundings of 24–28 °C.     

Hen egg white as a feeder protein for lipase immobilization

Enzyme stabilization via immobilization is one of the preferred processes as it provides the advantages of recovery and reusability. In this study, Thermomyces lanuginosus lipase has been immobilized through crosslinking using 2% glutaraldehyde and hen egg white, as an approach towards CLEA preparation. The immobilization efficiency and the properties of the immobilized enzyme in terms of stability to pH, temperature, and denaturants was studied and compared with the free enzyme. Immobilization efficiency of 56% was achieved with hen egg white. The immobilized enzyme displayed a shift in optimum pH towards the acidic side with an optimum at pH 4.0 whereas the pH optimum for free enzyme was at pH 6.0. The immobilized enzyme was stable at higher temperature retaining about 83% of its maximum activity as compared to the free enzyme retaining only 41% activity at 70 °C. The denaturation of lipase in free form was rapid with a half-life of 2 h at 60 °C and 58 min at 70 °C as compared to 12 h at 60 °C and 2 h at 70 °C for the immobilized enzyme. The effect of denaturants, urea and guanidine hydrochloride on the free and immobilized enzyme was studied and the immobilized enzyme was found to be more stable towards denaturants retaining 74% activity in 8 M urea and 98% in 6 M GndHCl as compared to 42% and 33% respectively in the case of free enzyme. The apparent K_m (2.08 mM) and apparent V_max (0.95 μmol/min) of immobilized enzyme was lower as compared to free enzyme; K_m (8.0 mM) and V_max (2.857 μmol/min). The immobilized enzyme was reused several times for the hydrolysis of olive oil.     

Calculations of binding affinity between C8-substituted GTP analogs and the bacterial cell-division protein FtsZ

The FtsZ protein is a self-polymerizing GTPase that plays a central role in bacterial cell division. Several C8-substituted GTP analogs are known to inhibit the polymerization of FtsZ by competing for the same binding site as its endogenous activating ligand GTP. Free energy calculations of the relative binding affinities to FtsZ for a set of five C8-substituted GTP analogs were performed. The calculated values agree well with the available experimental data, and the main contribution to the free energy differences is determined to be the conformational restriction of the ligands. The dihedral angle distributions around the glycosidic bond of these compounds in water are known to vary considerably depending on the physicochemical properties of the substituent at C8. However, within the FtsZ protein, this substitution has a negligible influence on the dihedral angle distributions, which fall within the narrow range of −140° to −90° for all investigated compounds. The corresponding ensemble average of the coupling constants ³ J(C4,H1′) is calculated to be 2.95 ± 0.1 Hz. The contribution of the conformational selection of the GTP analogs upon binding was quantified from the corresponding populations. The obtained restraining free energy values follow the same trend as the relative binding affinities to FtsZ, indicating their dominant contribution.     

Expression analysis of nine small heat shock protein genes from Tamarix hispida in response to different abiotic stresses and abscisic acid treatment

Heat shock proteins (HSPs) play important roles in protecting plants against environmental stresses. Furthermore, small heat shock proteins (sHSPs) are the most ubiquitous HSP subgroup with molecular weights ranging from 15 to 42 kDa. In this study, nine sHSP genes (designated as ThsHSP1–9) were cloned from Tamarix hispida. Their expression patterns in response to cold, heat shock, NaCl, PEG and abscisic acid (ABA) treatments were investigated in the roots and leaves of T. hispida by real-time RT-PCR analysis. The results showed that most of the nine ThsHSP genes were expressed at higher levels in roots than in leaves under normal growth condition. All of ThsHSP genes were highly induced under conditions of cold (4 °C) and different heat shocks (36, 40, 44, 48 and 52 °C). Under NaCl stress, all nine ThsHSPs genes were up-regulated at least one stress time-point in both roots and leaves. Under PEG and ABA treatments, the nine ThsHSPs showed various expression patterns, indicating a complex regulation pathway among these genes. This study represents an important basis for the elucidation of ThsHSP gene function and provides essential information that can be used for stress tolerance genetic engineering in future studies.     

Thermoregulation on the air–water interface—II: Foot conductance,activity metabolism and a two-dimensional heat transfer model

We used a quasi-adiabatic calorimeter and respirometry apparatus to measure heat loss from the feet of 3- to 4-d-old mallard ducklings (Anas platyrhynchos). We found that, at cool (<20 °C) operative temperatures, foot conductance increased in proportion to operative temperature, T_e, rather than water temperature. We combined these results with those of an earlier study to develop a heat transfer model for swimming ducklings. This model includes separate thermal conductances to air (0.027 W/°C-animal), to water through the down (0.035[1+2.05×10⁻⁷T_e⁴]) W/°C-animal, and to water through the feet (2.01×10⁻⁸T_e⁴ W/°C-animal). The overall conductance by all three routes is only 21% greater when swimming compared to standing in air at the same operative temperature. Interestingly, ducklings can maintain body temperature >39 °C while swimming in 5 °C water, but not when restrained in a calorimeter with 5 °C water. Peak oxygen consumption is greater when swimming, and apparently exercise metabolism substitutes almost completely for thermoregulatory heat production.     

Heat tolerance of developmental and seasonal stages of Chilo suppressalis

Global warming means that the ability to withstand heat stress is of crucial importance to insects' survival and reproduction. Insects have various ways of achieving thermal tolerance, which can be affected by thermal history, physiological state, and seasonal cycles. In this study, we compared the thermal tolerance of life stages and seasons of a wild population of the striped stem borer, Chilo suppressalis (Walker) (Lepidoptera: Pyralidae), an economically significant pest of rice crops in Asia. Our results demonstrate that the eggs, larvae, and adults of C. suppressalis collected in rice fields in Yangzhou, China, are able to tolerate extremely high temperatures, in excess of those this species encounters in nature. We found that egg masses had a survival rate of 75% after being kept at 42 °C for 8 h. Egg masses exposed to 39 °C for 8 h had the longest hatching time (3.3 days). LTemp₅₀ and LTemp₉₀ (i.e., the temperatures at which 50 or 90% of individuals died within 2 h) of larvae collected in late summer were 45.4 and 47.3 °C, respectively. LTime₅₀ and LTime₉₀ (i.e., the time required to kill 50 or 90% of individuals) at 44 °C were 6.2 and 9.6 h, respectively. The corresponding values for 46 °C were 1.5 and 2.6 h. We also found that the heat tolerance of adults collected in late summer was lower than that of larvae. For example, LTemp₅₀ of male and female adults was 43.8 and 43.6 °C, respectively. Other measures of the heat tolerance of adults, such as LTime₅₀ at 42 °C, also differed between the sexes, being 5.9 h for males and 7.2 h for females. Although adult survival was robust to heat stress, adult fertility was more sensitive. Our results also indicate that although the second generation of adults (i.e., the summer generation) typically encountered higher temperatures than the overwintering generation, survival of the second generation adults was lower.     

Differential protein expression for geothermal Agrostis scabra and turf-type Agrostis stolonifera differing in heat tolerance

Heat stress is a major factor limiting the growth of cool-season grasses in warm climatic regions by affecting many physiological processes, including protein metabolism. Protein degradation often occurs with increasing temperatures, but certain specific proteins such as heat shock proteins (HSPs) may be induced or enhanced in their expression under supraoptimal temperatures. The objectives of this study were to determine the critical temperature that causes protein induction or degradation in two Agrostis grass species differing in heat tolerance and to compare protein profiles between the two species under different temperature regimes. Plants of heat-tolerant Agrostis scabra and two cultivars of heat-sensitive Agrostis stolonifera (‘L-93’ and ‘Penncross’) were exposed to constant day/night temperatures of 20, 30, 35, 40, or 45 °C for 14 d. Leaf photochemical efficiency (Fv/Fm), chlorophyll and carotenoid contents, and soluble protein content declined with increasing temperatures. The decreases were the least severe for A. scabra, intermediate for ‘L-93’, and the most severe for ‘Penncross’, indicating interspecific and intraspecific variations in heat tolerance in Agrostis species. Protein degradation was observed at 30–45 °C in both cultivars of A. stolonifera, and at 40–45 °C in A. scabra.HSPs were induced or enhanced at 35–45 °C in ‘L-93’ and A. scabra, and at 40–45 °C in ‘Penncross’. Immunoblotting also revealed stronger expressions of HSP60 and HSP70 in A. scabra or ‘L-93’ than in ‘Penncross’ at 35–45 °C after 3 d. The results suggested the superior heat tolerance of Agrostis grass species and cultivars could be attributed to the early induction of HSPs, particularly small molecular weight (23 kDa), at a lower level of heat stress and the maintenance of protein thermostability, particularly high-molecular weight proteins (83 kDa and large units of Rubisco).     

Bat thermoregulation in the heat: Limits to evaporative cooling capacity in three southern African bats

High environmental temperatures pose significant physiological challenges related to energy and water balance for small endotherms. Although there is a growing literature on the effect of high temperatures on birds, comparable data are scarcer for bats. Those data that do exist suggest that roost microsite may predict tolerance of high air temperatures. To examine this possibility further, we quantified the upper limits to heat tolerance and evaporative cooling capacity in three southern African bat species inhabiting the same hot environment but using different roost types (crevice, foliage or cave). We used flow-through respirometry and compared heat tolerance limits (highest air temperature (T_a) tolerated before the onset of severe hyperthermia), body temperature (T_b), evaporative water loss, metabolic rate, and maximum cooling capacity (i.e., evaporative heat loss/metabolic heat production). Heat tolerance limits for the two bats roosting in more exposed sites, Taphozous mauritianus (foliage-roosting) and Eptesicus hottentotus (crevice-roosting), were T_a = ~44 °C and those individuals defended maximum T_b between 41 °C and 43 °C. The heat tolerance limit for the bat roosting in a more buffered site, Rousettus aegyptiacus (cave-roosting), was T_a = ~38 °C with a corresponding T_b of ~38 °C. These interspecific differences, together with a similar trend for higher evaporative cooling efficiency in species occupying warmer roost microsites, add further support to the notion that ecological factors like roost choice may have profound influences on physiological traits related to thermoregulation.     

Production of recombinant ghost bacterial vaccine against streptococcal disease of olive flounder

The simple fed-batch fermentation was carried out to produce E. coli XL1-Blue/pHCE-InaN-GAPDH Ghost 37 SDM as a ghost bacterial vaccine (GBV). The fermentation was carried out in four phases of batch fermentation (phase 1), fed-batch fermentation with intermittent feeding strategy (phase 2), thermal induction by temperature increase to 42 °C for the expression of lysis E gene (GBV formation, phase 3) and high temperature holding phase to increase the efficiency of GBV formation (phase 4). After the high temperature holding phase at 47 °C, efficiency of the GBV formation reached 99.7% with the culture OD₆₀₀ of 57.9. The maximum GBV of 22 g dcw/l was obtained. The protective efficacy of GBV was determined by a challenge test to immunized olive flounder using live Streptococcus iniae. In 14 days of challenge test, the positive and E. coli strain control groups showed 100% cumulative mortalities. Test groups immunized by formalin killed cell (FKC) vaccine, GBV with 42 °C and 47 °C heat shock showed 66%, 54% and 54% of cumulative mortalities, respectively. These results suggest that GBV showed the effectiveness for the protection from the streptococcal infection and had higher potential to induce protective antibodies than FKC vaccine.     

Effect of temperature on life table parameters of Plutella xylostella (Lepidoptera: Plutellidae) on two brassicaceous host plants

Life table parameters of diamondback moth, Plutella xylostella (L.), were studied at seven constant temperatures (10, 15, 20, 25, 28, 30, and 35 °C) on two brassicaceous host plants, cauliflower (Brassica oleracea var. botrytis) and cabbage (Brassica oleracea var. capitata). Survival, longevity and reproduction were examined and used to construct a life table. The survival at immature stages varied from 53.0 to 84.1% on cauliflower and from 58.3 to 86.2% on cabbage at 10–30 °C. P. xylostella did not survive at 35 °C. The female adult longevity ranged from 12.9 days at 30 °C to 30.4 days at 10 °C on cauliflower and 9.7 days at 30 °C to 40.0 days at 15 °C on cabbage. The net reproductive rate (R₀) increased with increasing temperature, while generation time (T) decreased. This caused the intrinsic rate of increase (r_m) to increase from 0.038 to 0.340 on cauliflower and 0.033 to 0.315 on cabbage from 10 to 28 °C. The significant decrease in R₀ caused a decrease in r_m at 30 °C. The r_m values on cauliflower were significantly higher than cabbage at 15, 20, 28 and 30 °C.     

Interaction between eggshell temperature and carbon dioxide concentration after day 8 of incubation on broiler chicken embryo development

Carbon dioxide (CO₂) is considered to be an important factor during incubation of eggs. Effects attributed to higher CO₂ concentrations during experiment might be due to confounding effects of other environmental conditions, such as incubation temperature. To disentangle effects of eggshell temperature (EST) and CO₂ concentration, an experiment was conducted. A total of 630 Cobb 500 hatching eggs from 37 to 45 wk commercial breeder flocks were collected and incubated according to treatments. The experiment was setup as a complete randomized 2 × 3 factorial design, resulting in 6 treatments. From day 8 of incubation onward, broiler eggs were exposed to one of two EST (37.8 or 38.9 °C) and one of three CO₂ concentrations (0.1, 0.4 or 0.8%). Eggs were incubated in climate-respiration chambers and metabolic heat production was determined continuously. At day 18 of incubation and at 6 h after hatching, embryo and chicken quality were determined by evaluation of organ weights, navel condition, blood metabolites and hepatic glycogen. Hatching time and chicken length at 6 h after hatching showed an interaction between EST and CO₂ concentration (both P = 0.001). Furthermore, no effect of CO₂ concentration was found on embryo development or chicken quality. Metabolic heat production between day 8 and 18 of incubation was not affected by either EST or CO₂. At day 18 of incubation, an EST of 38.9 °C resulted in a higher egg weight loss, longer embryos, higher yolk free body mass (YFBM) and lower heart weight than an EST of 37.8 °C (all P < 0.008). At 6 h after hatching, an EST of 38.9 °C resulted in a higher residual yolk weight and lower YFBM, liver weight and heart weight than an EST of 37.8 °C (all P < 0.003). Lactate, uric acid and hepatic glycogen were not affected by EST at either day 18 of incubation or at hatch. Glucose was not affected by EST at day 18 of incubation, but at hatch, it was higher at an EST of 37.8 °C than at an EST of 38.9 °C (P = 0.02). It can be concluded that effects of CO₂ concentration (at concentrations ≤0.8%) on embryonic development and chicken quality appear to be limited when EST is maintained at a constant level. Moreover, a higher EST from day 8 of incubation onward appears to negatively affect chicken quality at hatch.     

UBQLN2 undergoes a reversible temperature-induced conformational switch that regulates binding with HSPA1B: ALS/FTD mutations cripple the switch but do not destroy HSPA1B binding

Here we present evidence, based on alterations of its intrinsic tryptophan fluorescence, that UBQLN2 protein undergoes a conformational switch when the temperature is raised from 37 °C to 42 °C. The switch is reset on restoration of the temperature. We speculate that the switch regulates UBQLN2 function in the heat shock response because elevation of the temperature from 37 °C to 42 °C dramatically increased in vitro binding between UBQLN2 and HSPA1B. Furthermore, restoration of the temperature to 37 °C decreased HSPA1B binding. By comparison to wild type (WT) UBQLN2, we found that all five ALS/FTD mutant UBQLN2 proteins we examined had attenuated alterations in tryptophan fluorescence when shifted to 42 °C, suggesting that the conformational switch is crippled in the mutants. Paradoxically, all five mutants bound similar amounts of HSPA1B compared to WT UBQLN2 protein at 42 °C, suggesting that either the conformational switch is not instrumental for HSPA1B binding, or that, although damaged, it is still functional. Comparison of the poly-ubiquitin chain binding revealed that WT UBQLN2 binds more avidly with K63 than with K48 chains. The avidity may explain the involvement of UBQLN2 in autophagy and cell signaling. Consistent with its function in autophagy, we found UBQLN2 binds directly with LC3, the autophagosomal-specific membrane-tethered protein. Finally, we provide evidence that WT UBQLN2 can homodimerize, and heterodimerize with WT UBQLN1. We show that ALS mutant P497S-UBQLN2 protein can oligomerize with either WT UBQLN1 or 2, providing a possible mechanism for how mutant UBQLN2 proteins could bind and inactivate UBQLN proteins, causing loss of function.     

Survival and growth of microscopic fungi derived from tropical regions under future heat waves in the Pannonian Biogeographical Region

Warming and heat waves are predicted by different climate models in the near future in the Pannonian Biogeographical Region (PBR). These climatic effects may have impact on the prevalence and distribution of certain fungal species of this area. In this study the effects of predicted climate scenarios were tested on fungi being endemic or unintentionally introduced by global trade from regions of warm temperate climate. Common fungal species were selected for the study and exposed to heat waves during 7 days according to two climate scenarios: one moderately (RCP 4.5, T_avg = 27 °C, T_max = 35 °C, RH: 100%) and one strongly pessimistic (RCP 8.5, T_avg = 30 °C, T_max = 40 °C, RH: 100%) that include predictions for the Central Hungarian Region for July 2050. According to our results, Aspergillus flavus, Aspergillus niger, Aspergillus tubingensis and Fusarium strains introduced from tropical regions tolerated heat waves, unlike Penicillium and Talaromyces spp. and endemic Cladosporium spp. which were unable to grow under the RCP 8.5 treatment. The effects of climate change on fungi raise new issues not only from economic and health perspectives, but also in relation with plant protection and environment. Our results suggest that heat waves driven by climate change promote the colonization and growth of the tested strains of non-native fungi more likely than that of the native ones.