Computational analyses of amino acid molecules of heat shock protein-70 for elucidating its evolutionary diversity and protein interactions in selected farm animals

Background The heat shock protein-70 (HSP70) is a protein associated with response and adaptation to stress, as well as protection of the cells against thermal and oxidative stress in animals. It is an evolutionarily conserved protein, but its expression has been reportedly varied. Therefore, this study implemented computational analyses of the amino acid sequences of this gene for a better understanding of the evolutionary and protein interactions variations associated with the gene to facilitate its exploitation for the breeding of animals with increasing adaptation to heat stress. Results The result showed that there is a wide evolutionary distance between humans and the selected farm animals studied but elegans shared a common evolutionary relationship with the farm animals. The sequence identity analysis returned exact matches among the sequences as minimum = 8.09%, maximum = 98.58%, and mean ± SD = 71.03 ± 26.3% across all the species, while the sequence similarities resemblance among the sequences were minimum = 16.49%, maximum = 100%, and mean ± SD = 78.99 ± 24.39%. The global block substitution matrix (BLOSUM62) analysis returned minimum = 0.18, maximum = 0.98, and mean ± SD = 0.62 ± 0.34. The analysis of the molecular weight of the protein sequences returned minimum = 5.70 kDa, maximum = 6.41 kDa, mean = 6.28 kDa, and standard deviation 0.17 kDa, and the isoelectric point of the protein sequences was minimum = 4.55, maximum = 7.17, mean = 5.56, and standard deviation = 0.65 while the hydrophobicity of the protein sequences were minimum = 45.20 kcal/mol, maximum = 53.02 kcal/mol, mean = 47.81 kcal/mol, and standard deviation = 1.85 kcal/mol. Conclusion The outcomes of the computational analyses led to the conclusion that variations exist in the conservations of amino acid residues of the gene in the studied farm and non-farm animals, and this is responsible for the differences and similarities in the expression of the HSP70 gene in different animals. It was also concluded that elegans are suitable model that could be exploited for a better understanding of response and adaptation to heat stress in duck, chicken, cattle, sheep, and goat when focusing on regulation and expression of heat shock protein gene 70 (HSP70).

Arabidopsis Target of Rapamycin Coordinates With Transcriptional and Epigenetic Machinery to Regulate Thermotolerance

Global warming exhibits profound effects on plant fitness and productivity. To withstand stress, plants sacrifice their growth and activate protective stress responses for ensuring survival. However, the switch between growth and stress is largely elusive. In the past decade, the role of the target of rapamycin (TOR) linking energy and stress signalling is emerging. Here, we have identified an important role of Glucose (Glc)-TOR signalling in plant adaptation to heat stress (HS). Glc via TOR governs the transcriptome reprogramming of a large number of genes involved in heat stress protection. Downstream to Glc-TOR, the E2Fa signalling module regulates the transcription of heat shock factors through direct recruitment of E2Fa onto their promoter regions. Also, Glc epigenetically regulates the transcription of core HS signalling genes in a TOR-dependent manner. TOR acts in concert with p300/CREB HISTONE ACETYLTRANSFERASE1 (HAC1) and dictates the epigenetic landscape of HS loci to regulate thermotolerance. Arabidopsis plants defective in TOR and HAC1 exhibited reduced thermotolerance with a decrease in the expression of core HS signalling genes. Together, our findings reveal a mechanistic framework in which Glc-TOR signalling through different modules integrates stress and energy signalling to regulate thermotolerance.

Future heat adaptation and exposure among urban populations and why a prospering economy alone won’t save us

When inferring on the magnitude of future heat-related mortality due to climate change, human adaptation to heat should be accounted for. We model long-term changes in minimum mortality temperatures (MMT), a well-established metric denoting the lowest risk of heat-related mortality, as a function of climate change and socio-economic progress across 3820 cities. Depending on the combination of climate trajectories and socio-economic pathways evaluated, by 2100 the risk to human health is expected to decline in 60% to 80% of the cities against contemporary conditions. This is caused by an average global increase in MMTs driven by long-term human acclimatisation to future climatic conditions and economic development of countries. While our adaptation model suggests that negative effects on health from global warming can broadly be kept in check, the trade-offs are highly contingent to the scenario path and location-specific. For high-forcing climate scenarios (e.g. RCP8.5) the maintenance of uninterrupted high economic growth by 2100 is a hard requirement to increase MMTs and level-off the negative health effects from additional scenario-driven heat exposure. Choosing a 2 °C-compatible climate trajectory alleviates the dependence on fast growth, leaving room for a sustainable economy, and leads to higher reductions of mortality risk.

A Multi-environment Framework to Evaluate the Adaptation of Wheat (Triticum Aestivum) to Heat Stress

Adaptation of wheat to heat stress is an important component of adaptation in variable climates such as the cereal producing areas of Australia. However, in variable climates stress conditions may not be present in every season or is present at different levels, at different times during the season. Such conditions complicate plant breeder’s ability to select for adaptation to abiotic stress. This study presents a framework for the assessment of the genetic basis of adaptation to heat stress conditions with improved relevance to breeder’s selection objectives. The framework was applied here with the evaluation of 1225 doubled haploid lines from five populations across six environments (three environments selected for contrasting temperature stress conditions during anthesis and grain fill periods, over two consecutive seasons), using regionally best practice planting times to evaluate the role of heat stress conditions in genotype adaptation. Temperature co-variates were determined for each genotype, in each environment, for the anthesis and grain fill periods. Genome wide QTL analysis identified performance QTL for stable effects across all environments, and QTL that illustrated responsiveness to heat stress conditions across the sampled environments. A total of 199 QTL were identified, including 60 performance QTL, and 139 responsiveness QTL. Of the identified QTL, 99 occurred iseparate to the 21 anthesis date QTL identified. Assessing adaptation to heat stress conditions as the combination of performance and responsiveness offers breeders opportunities to select for grain yield stability across a range of environments, as well as genotypes with higher relative yield in stress conditions.

Evolution of the threshold temperature definition of a heat wave vs. evolution of the minimum mortality temperature: a case study in Spain during the 1983–2018 period

Background An area of current study concerns analysis of the possible adaptation of the population to heat, based on the temporal evolution of the minimum mortality temperature (MMT). It is important to know how is the evolution of the threshold temperatures (Tthreshold) due to these temperatures provide the basis for the activation of public health prevention plans against high temperatures. The objective of this study was to analyze the temporal evolution of threshold temperatures (Tthreshold) produced in different Spanish regions during the 1983–2018 period and to compare this evolution with the evolution of MMT. The dependent variable used was the raw rate of daily mortality due to natural causes ICD X: (A00-R99) for the considered period. The independent variable was maximum daily temperature (Tmax) during the summer months registered in the reference observatory of each region. Threshold values were determined using dispersion diagrams (annual) of the prewhitened series of mortality temperatures and Tmax. Later, linear fit models were carried out between the different values of Tthreshold throughout the study period, which permitted detecting the annual rate of change in Tthreshold. Results The results obtained show that, on average, Tthreshold has increased at a rate of 0.57 ºC/decade in Spain, while Tmax temperatures in the summer have increased at a rate of 0.41 ºC/decade, suggesting adaptation to heat. This rate of evolution presents important geographic heterogeneity. Also, the rate of evolution of Tthreshold was similar to what was detected for MMT. Conclusions The temporal evolution of the series of both temperature measures can be used as indicators of population adaptation to heat. The temporal evolution of Tthreshold has important geographic variation, probably related to sociodemographic and economic factors, that should be studied at the local level.