scholarly journals The use of high throughput phenotyping for assessment of heat stress-induced changes in Arabidopsis

2019 ◽  
Author(s):  
Ge Gao ◽  
Mark A. Tester ◽  
Magdalena M. Julkowska

AbstractThe worldwide rise in heatwave frequency poses a threat to plant survival and productivity. Determining the new marker phenotypes that show reproducible response to heat stress and contribute to heat stress tolerance is becoming a priority. In this study, we describe a protocol focusing on the daily changes in plant morphology and photosynthetic performance after exposure to heat stress using an automated non-invasive phenotyping system. Heat stress exposure resulted in an acute reduction of quantum yield of photosystem II and increased leaf angle. In the longer term, exposure to heat also affected plant growth and morphology. By tracking the recovery period of WT and mutants impaired in thermotolerance (hsp101), we observed that the difference in maximum quantum yield, quenching, rosette size, and morphology. By examining the correlation across the traits throughout time, we observed that early changes in photochemical quenching corresponded with the rosette size at later stages, which suggests the contribution of quenching to overall heat tolerance. We also determined that 6h of heat stress provides the most informative insight in plant responses to heat, as it shows a clear separation between treated and non-treated plants as well as WT and hsp101. Our work streamlines future discoveries by providing an experimental protocol, data analysis pipeline and new phenotypes that could be used as targets in thermotolerance screenings.

2020 ◽  
Vol 2020 ◽  
pp. 1-14 ◽  
Author(s):  
Ge Gao ◽  
Mark A. Tester ◽  
Magdalena M. Julkowska

The worldwide rise in heatwave frequency poses a threat to plant survival and productivity. Determining the new marker phenotypes that show reproducible response to heat stress and contribute to heat stress tolerance is becoming a priority. In this study, we describe a protocol focusing on the daily changes in plant morphology and photosynthetic performance after exposure to heat stress using an automated noninvasive phenotyping system. Heat stress exposure resulted in an acute reduction of the quantum yield of photosystem II and increased leaf angle. In longer term, the exposure to heat also affected plant growth and morphology. By tracking the recovery period of the WT and mutants impaired in thermotolerance (hsp101), we observed that the difference in maximum quantum yield, quenching, rosette size, and morphology. By examining the correlation across the traits throughout time, we observed that early changes in photochemical quenching corresponded with the rosette size at later stages, which suggests the contribution of quenching to overall heat tolerance. We also determined that 6 h of heat stress provides the most informative insight in plant’s responses to heat, as it shows a clear separation between treated and nontreated plants as well as the WT and hsp101. Our work streamlines future discoveries by providing an experimental protocol, data analysis pipeline, and new phenotypes that could be used as targets in thermotolerance screenings.


2021 ◽  
Author(s):  
Daniel Buszewicz ◽  
Łucja Maria Kowalewska ◽  
Radosław Mazur ◽  
Marta Zajbt-Łuczniewska ◽  
Liliana Surmacz ◽  
...  

Polyprenols are ubiquitous isoprenoid compounds that accumulate in large quantities in plant photosynthetic tissues. While our knowledge of polyprenol biochemistry is constantly expanding, the regulation of their biosynthesis as well as the molecular basis of their cellular action are still poorly understood. In Arabidopsis, the polyprenols Pren-9, -10 and -11, synthesized by cis-prenyltransferase 7 (CPT7), are localized in plastidial membranes and affect the photosynthetic performance of chloroplasts. In this report we present evidence that plastidial polyprenols are among the major constituents of thylakoid membranes. Disturbances in polyprenol level, caused by alterations in CPT7 expression, change chloroplast ultrastructure, affect aggregation of LHCII complexes and modulate non-photochemical quenching (NPQ). Moreover, we show that Arabidopsis responds to high temperature by upregulating expression of CPT7 and increasing the accumulation of CPT7-derived polyprenols. These heat-induced changes in polyprenol biosynthesis are mediated by Heat Shock Transcription Factors of the HSFA1 family, the master regulators of heat stress response. Collectively, results presented in this report bring us closer to understanding the mechanisms by which polyprenols affect plant physiology and provide an additional link between chloroplast biology and plant responses to changing environmental conditions.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1631
Author(s):  
Aida Shomali ◽  
Sasan Aliniaeifard ◽  
Fardad Didaran ◽  
Mahmoud Lotfi ◽  
Mohammad Mohammadian ◽  
...  

GABA (gamma-aminobutyric acid) and melatonin are endogenous compounds that enhance plant responses to abiotic stresses. The response of Vicia faba to different stressors (salinity (NaCl), poly ethylene glycol (PEG), and sulfur dioxide (SO2)) was studied after priming with sole application of GABA and melatonin or their co-application (GABA + melatonin). Both melatonin and GABA and their co-application increased leaf area, number of flowers, shoot dry and fresh weight, and total biomass. Plants treated with GABA, melatonin, and GABA + melatonin developed larger stomata with wider aperture compared to the stomata of control plants. The functionality of the photosynthetic system was improved in primed plants. To investigate the photosynthetic functionality in details, the leaf samples of primed plants were exposed to different stressors, including SO2, PEG, and NaCl. The maximum quantum yield of photosystem II (PS II) was higher in the leaf samples of primed plants, while the non-photochemical quenching (NPQ) of primed plants was decreased when leaf samples were exposed to the stressors. Correlation analysis showed the association of initial PIabs with post-stress FV/FM and NPQ. Stressors attenuated the association of initial PIabs with both FV/FM and NPQ, while priming plants with GABA, melatonin, or GABA + melatonin minimized the effect of stressors by attenuating these correlations. In conclusion, priming plants with both GABA and melatonin improved growth and photosynthetic performance of Vicia faba and mitigated the effects of abiotic stressors on the photosynthetic performance.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bin Huang ◽  
Zhinuo Huang ◽  
Ruifang Ma ◽  
Jialu Chen ◽  
Zhijun Zhang ◽  
...  

AbstractHeat shock transcription factors (HSFs) are central elements in the regulatory network that controls plant heat stress response. They are involved in multiple transcriptional regulatory pathways and play important roles in heat stress signaling and responses to a variety of other stresses. We identified 41 members of the HSF gene family in moso bamboo, which were distributed non-uniformly across its 19 chromosomes. Phylogenetic analysis showed that the moso bamboo HSF genes could be divided into three major subfamilies; HSFs from the same subfamily shared relatively conserved gene structures and sequences and encoded similar amino acids. All HSF genes contained HSF signature domains. Subcellular localization prediction indicated that about 80% of the HSF proteins were located in the nucleus, consistent with the results of GO enrichment analysis. A large number of stress response–associated cis-regulatory elements were identified in the HSF upstream promoter sequences. Synteny analysis indicated that the HSFs in the moso bamboo genome had greater collinearity with those of rice and maize than with those of Arabidopsis and pepper. Numerous segmental duplicates were found in the moso bamboo HSF gene family. Transcriptome data indicated that the expression of a number of PeHsfs differed in response to exogenous gibberellin (GA) and naphthalene acetic acid (NAA). A number of HSF genes were highly expressed in the panicles and in young shoots, suggesting that they may have functions in reproductive growth and the early development of rapidly-growing shoots. This study provides fundamental information on members of the bamboo HSF gene family and lays a foundation for further study of their biological functions in the regulation of plant responses to adversity.


2018 ◽  
Vol 19 (11) ◽  
pp. 3519 ◽  
Author(s):  
Agustina Bernal-Vicente ◽  
Daniel Cantabella ◽  
Cesar Petri ◽  
José Hernández ◽  
Pedro Diaz-Vivancos

Salinity is considered as one of the most important abiotic challenges that affect crop productivity. Plant hormones, including salicylic acid (SA), are key factors in the defence signalling output triggered during plant responses against environmental stresses. We have previously reported in peach a new SA biosynthetic pathway from mandelonitrile (MD), the molecule at the hub of the cyanogenic glucoside turnover in Prunus sp. In this work, we have studied whether this new SA biosynthetic pathway is also present in plum and the possible role this pathway plays in plant plasticity under salinity, focusing on the transgenic plum line J8-1, which displays stress tolerance via an enhanced antioxidant capacity. The SA biosynthesis from MD in non-transgenic and J8-1 micropropagated plum shoots was studied by metabolomics. Then the response of J8-1 to salt stress in presence of MD or Phe (MD precursor) was assayed by measuring: chlorophyll content and fluorescence parameters, stress related hormones, levels of non-enzymatic antioxidants, the expression of two genes coding redox-related proteins, and the content of soluble nutrients. The results from in vitro assays suggest that the SA synthesis from the MD pathway demonstrated in peach is not clearly present in plum, at least under the tested conditions. Nevertheless, in J8-1 NaCl-stressed seedlings, an increase in SA was recorded as a result of the MD treatment, suggesting that MD could be involved in the SA biosynthesis under NaCl stress conditions in plum plants. We have also shown that the plum line J8-1 was tolerant to NaCl under greenhouse conditions, and this response was quite similar in MD-treated plants. Nevertheless, the MD treatment produced an increase in SA, jasmonic acid (JA) and reduced ascorbate (ASC) contents, as well as in the coefficient of non-photochemical quenching (qN) and the gene expression of Non-Expressor of Pathogenesis-Related 1 (NPR1) and thioredoxin H (TrxH) under salinity conditions. This response suggested a crosstalk between different signalling pathways (NPR1/Trx and SA/JA) leading to salinity tolerance in the transgenic plum line J8-1.


1996 ◽  
Vol 270 (6) ◽  
pp. F1057-F1065 ◽  
Author(s):  
Y. H. Wang ◽  
S. C. Borkan

The 72-kDa heat stress protein (HSP-72) is an inducible cytoprotectant protein. Although transient renal ischemia in vivo induces HSP-72, it is not known whether prior heat stress protects renal epithelial cells from injury mediated by ATP depletion. To evaluate this hypothesis, opossum kidney (OK) cells were exposed to sodium cyanide and 2-deoxy-D-glucose in the absence of medium glucose, a maneuver that reduced cell ATP content to < 10% of the control value within 10 min and decreased cell survival. One day after 2 h of ATP depletion, OK cells previously exposed to heat stress (to induce accumulation of HSP-72) exhibited marked improvement in survival (a > 4-fold increase in total DNA), less uptake of vital dye, and less release of lactate dehydrogenase (LDH) than cells subjected to ATP depletion alone (23.0 +/- 1.6 vs. 34.1 +/- 1.2% of total LDH, respectively). Enhanced clonogenicity post-heat stress was completely prevented by cycloheximide and positively correlated with the steady-state content of HSP-72. In the recovery period after ATP depletion, cell ATP content, maximum mitochondrial ATP production rate, and total LDH activity were all significantly higher in cells with abundant HSP-72. Although the protective effects associated with heat stress are likely to be multifactoral, preserved cell metabolism and higher ATP content could enhance cellular repair processes after ATP depletion.


2018 ◽  
Vol 56 ◽  
pp. 136-140
Author(s):  
G. S. Sharapa ◽  
O. V. Boyko

Scientific and production experiments were carried out on cows of Ukrainian Black-and-White diary breed (UBAWD) of SE "Seagull" (branch "Lisne") during 2016–2017. The anatomical and physiological state of genital organs of cows was determined by the method of clinical and gynecological research of animals before conducting experiments and during them every 40–50 days. In total 486 cows were kept under control, which were kept in typical rooms with running platforms, but the active motivation of animals was clearly insufficient. Feeding cows according to the recommended standards. The milk yield from the cow in 2017 was 7813 kg. The experiments studied the effect of feeding cows during the dry period, the conditions of retention and some other paratypic factors on the course of the genera and the postnatal period, the duration of the service period and the fertility of cows. In analyzing the research results, personal records and veterinary documentation were used. In conducting experiments, it was found that normal calving was in 89% of cows, and severe and pathological – in 11% of cases. The main diseases in the afterlife period were: detention of the litter – 9.5%, postpartum endometritis – 21.5%, hypofunction of the ovaries – 23.0%, persistent yellow ovarian bodies – 25.6% and others. Normal intervals between stages of excitation of the sexual cycle (18–22 days) were in 63% of cows, and violations of the rhythm of sexual cycle, associated with dysfunction of the ovaries and missed the hunt – 30% of animals. Subunvulation of the genital organs of the cows contributed to the diseases of the limbs, udder and digestive disorders. During 2016–2017, the effect of feeding cows (173 g.) in the dry period on the course of calving, post-autumn period and their fertility was studied. Under the same conditions, keeping cows in the maternity ward and feeding rough and succulent feeds concentrated feeds fed cows of the control group (98 heads) to 1–2 kg daily during the dry period, and experimental (75 heads) – for 18–20 days to calving 2–3 kg. A positive difference was found in favor of cows of the experimental group: there was a more active stage of expulsion of the fetus, less delay of the placenta (by 7%) and endometritis (by 12%), the duration of the postoperative regenerative period decreased by 8.6 days; service period – 19.0 days; fertility from two inseminans was higher by 5.7%. Study of the reproductive capacity of cows at the hotel in different seasons showed that the recovery period was shorter by 11 days in the presence of cows in 3–4 quarters, and the service period – by 23.2 days at hotel in I and IV sq. The average duration of the recovery period was 79.5 days, while the service period was 123.4 days. The longest duration of the joint ventricle was in cows at hotel during the hot summer days of the year. The average fertilization rate from the first insemination of 339 cows was 44.9% with fluctuations in individual groups of milkers from 26.8% to 55.0%. The following indicators were in the number 1 and number 3 (respectively 26.8% and 31.4%). The best fertility rates were in groups № 4, 6 and 7, where there were more cows of the second and third lactation, and the responsible attitude of the milkers to work in organizing cows walks and sexually explicit hunting. When comparing the assessment of the duration of the IP and SP in full-age cows and cows, the first-born, taking into account 225 goals. It was found that these indicators were longer in primitive cows – 20.7 days respectively and 21.9 days in relation to full-age cows. The obtained results are completely consistent with the results obtained by a number of both domestic and foreign researchers. More attention is needed to grow heifers and to prepare newborns for delivery. In 15–17% of cows at and after the hotel, gynecological diseases that occurred in the presence of gastrointestinal diseases, lameness, mastitis and others were diagnosed. This has negatively affected the overall performance of the herd. In studying the duration of HP and SP in healthy and sick cows after calving, it was found that if the SP in healthy cows lasts 73.4 days, then in patients – 116.3 days (the difference was 42.9 days), and the difference in the duration of the joint venture reached 98.7 days. On the basis of the results of the research, it can be concluded that the reproductive function of the cows is influenced by such paratypic factors as feeding animals in the dry period, the temperature factor (time of year), the human factor (the effect of milking on a group of cows), age and physiological state of cows in the hotel and in the afterlife period. When feeding 2–3 kg of bovine feed for cows, together with rough and juicy fodder for 18–20 days prior to calving, the recovery period decreased by 8.6 days and service period – by 19 days, and fertility from two inseminals increased by 5.7%, reaching 85.3%. The smallest duration of the service-period was in the presence of cows in the I and IV quarters year (107.7–117.1 days). In primary cows, the recovery period was longer than that of full-age cows by 20.7 days, and the service period was 21.9 days. In the physiologically healthy cows after calving, the recovery period lasted an average of 73.4 days and service period – 98.7 days, and in patients, after the prescribed treatment – respectively 116.3 days and 197.4 days.


2021 ◽  
Vol 12 ◽  
Author(s):  
Gábor Bernát ◽  
Tomáš Zavřel ◽  
Eva Kotabová ◽  
László Kovács ◽  
Gábor Steinbach ◽  
...  

Photomorphogenesis is a process by which photosynthetic organisms perceive external light parameters, including light quality (color), and adjust cellular metabolism, growth rates and other parameters, in order to survive in a changing light environment. In this study we comprehensively explored the light color acclimation of Cyanobium gracile, a common cyanobacterium in turbid freshwater shallow lakes, using nine different monochromatic growth lights covering the whole visible spectrum from 435 to 687 nm. According to incident light wavelength, C. gracile cells performed great plasticity in terms of pigment composition, antenna size, and photosystem stoichiometry, to optimize their photosynthetic performance and to redox poise their intersystem electron transport chain. In spite of such compensatory strategies, C. gracile, like other cyanobacteria, uses blue and near far-red light less efficiently than orange or red light, which involves moderate growth rates, reduced cell volumes and lower electron transport rates. Unfavorable light conditions, where neither chlorophyll nor phycobilisomes absorb light sufficiently, are compensated by an enhanced antenna size. Increasing the wavelength of the growth light is accompanied by increasing photosystem II to photosystem I ratios, which involve better light utilization in the red spectral region. This is surprisingly accompanied by a partial excitonic antenna decoupling, which was the highest in the cells grown under 687 nm light. So far, a similar phenomenon is known to be induced only by strong light; here we demonstrate that under certain physiological conditions such decoupling is also possible to be induced by weak light. This suggests that suboptimal photosynthetic performance of the near far-red light grown C. gracile cells is due to a solid redox- and/or signal-imbalance, which leads to the activation of this short-term light acclimation process. Using a variety of photo-biophysical methods, we also demonstrate that under blue wavelengths, excessive light is quenched through orange carotenoid protein mediated non-photochemical quenching, whereas under orange/red wavelengths state transitions are involved in photoprotection.


Author(s):  
V. Jaldhani ◽  
D. Sanjeeva Rao ◽  
P. Beulah ◽  
B. Srikanth ◽  
P. R. Rao ◽  
...  

Aims: To assess heat-induced PSII damage and efficiency in eight promising backcross introgression lines (BC2F6) of KMR-3R/N22 possessing qHTSF1.1 and qHTSF4.1. Study Design:  Randomized Complete Block Design (RCBD) with three replications. Place and Duration of Study: ICAR-Indian Institute of Rice Research, Hyderabad India during wet/rainy (Kharif) season 2018. Methodology: Eight ILs (BC2F6) and parents were evaluated for heat tolerance. The high- temperature stress was imposed by enclosing the crop with a poly cover tent (Polyhouse) just before the anthesis stage. The fluorescence parameters viz., maximum efficiency of PSII photochemistry (Fv/Fm), Electron transport rate (ETR), effective PSII quantum yield (ΦPSII), coefficient of photochemical quenching (qP) and coefficient of non-photochemical quenching (qN) were measured under ambient and high-temperature stress. Results: The heat-tolerance potential of ILs was assessed in terms of PSII activity. The results indicated that significant differences were observed between treatments (T), genotypes (G) and the interaction between T × G.  The physiological basis of introgressed QTLs controls the spikelet fertility by maintaining the productive and adaptive strategies in heat-tolerant QTL introgressed lines with stable photosynthetic apparatus (PSII) under high-temperature stress. Conclusion: The Fv/Fm ratio denotes the maximum quantum yield of PSII. The heat-tolerant QTL introgressed lines exhibited stable photosynthetic apparatus (PSII) and noted better performance under high-temperature stress. They may be used as donors for fluorescence traits in breeding rice for high-temperature tolerance.


Sign in / Sign up

Export Citation Format

Share Document