Synonymous mutation of miR396a target sites in Growth Regulating Factor 15 (GRF15) enhances photosynthetic efficiency and heat tolerance in poplar

Abstract Heat stress damages plant tissues and induces multiple adaptive responses. Complex and spatiotemporally specific interactions among transcription factors (TFs), microRNAs (miRNAs), and their target genes play crucial roles in regulating stress responses. To explore these interactions and identify the regulatory networks in perennial woody plants, we integrated time-course RNA-seq, small RNA-seq, degradome sequencing, weighted gene correlation network analysis, and multi-gene association approaches in poplar. The results allowed for constructing a three-layer, highly interwoven regulatory network involving 15 TFs, 45 miRNAs, and 77 photosynthetic genes. Candidate gene association studies in the population of Populus tomentosa identified 114 significant associations and 696 epistatic SNP–SNP pairs which were linked to 29 photosynthetic and growth traits (P < 0.0001, q < 0.05). Finally, we identified miR396a and its target, Growth-Regulating Factor 15 (GRF15) as an important regulatory module in the heat stress response. Transgenic oxPagGRF15 plants expressing a GRF15 mRNA that lacks miR396a target sites exhibited enhanced heat tolerance and photosynthetic efficiency compared to wild-type plants. Together, these observations demonstrate that GRF15 plays a crucial role in responding to heat stress and validate the power of this new, multifaceted approach for identifying regulatory nodes in plants.

Download Full-text

Population structure, marker-trait association and identification of candidate genes for terminal heat stress relevant traits in bread wheat (Triticum aestivum L. em Thell)

Plant Genetic Resources ◽

10.1017/s1479262120000131 ◽

2020 ◽

Vol 18 (3) ◽

pp. 168-178

Author(s):

Devender Sharma ◽

Jai Prakash Jaiswal ◽

Navin Chander Gahtyari ◽

Anjana Chauhan ◽

Rashmi Chhabra ◽

...

Keyword(s):

Population Structure ◽

Heat Stress ◽

Candidate Genes ◽

Bread Wheat ◽

Ssr Markers ◽

Stress Responses ◽

Vegetation Index ◽

Association Studies ◽

Trait Association

AbstractGenetic improvement along with widened crop base necessitates for the detailed understanding of the genetic diversity and population structure in wheat. The present investigation reports the discovery of a total of 182 alleles by assaying 52 simple sequence repeats (SSRs) on 40 genotypes of bread wheat. Unweighted neighbour-joining method grouped these genotypes into two main clusters. Highly heat tolerant and intermediate tolerant cultivars were grouped in the same cluster, whereas remaining genotypes, particularly sensitive ones, were assigned different cluster. Similarly, the entire population was structured into two sub-populations (K = 2), closely corresponding with the other distance-based clustering patterns. The marker-trait association was discovered for four important physiological parameters, viz. canopy temperature depression, membrane thermostability index (MSI), normalized difference vegetation index and heat susceptibility index, indicating for heat stress (HS) tolerance in wheat. Both general and mixed linear models of association studies during 2017 and 2018, revealed the association of SSR markers, wmc222 (17.60%, PV) and gwm34 (20.70%, PV) with the mean phenotypic value of MSI. Likewise, SSR markers barc183, gwm75, gwm11 and cfd7 revealed a unique relationship with four selected physiological traits. Candidate genes discovered using in silico tools had nine SSR markers within the genic regions reported to play a role in heat and drought stress responses in plants. The information generated about these genic regions may be explored further in expression studies in-vivo to impart HS tolerance in bread wheat.

Download Full-text

Identification of QTLs affecting post-anthesis heat stress responses in European bread wheat

Theoretical and Applied Genetics ◽

10.1007/s00122-021-04008-5 ◽

2022 ◽

Author(s):

Gaëtan Touzy ◽

Stéphane Lafarge ◽

Elise Redondo ◽

Vincent Lievin ◽

Xavier Decoopman ◽

...

Keyword(s):

Heat Stress ◽

Bread Wheat ◽

Heat Tolerance ◽

Stress Responses ◽

Grain Weight ◽

High Yield ◽

Wheat Varieties ◽

Stay Green ◽

A Genome ◽

Main Effect

Abstract Key message The response of a large panel of European elite wheat varieties to post-anthesis heat stress is influenced by 17 QTL linked to grain weight or the stay-green phenotype. Abstract Heat stress is a critical abiotic stress for winter bread wheat (Triticum aestivum L.) especially at the flowering and grain filling stages, limiting its growth and productivity in Europe and elsewhere. The breeding of new high-yield and stress-tolerant wheat varieties requires improved understanding of the physiological and genetic bases of heat tolerance. To identify genomic areas associated with plant and grain characteristics under heat stress, a panel of elite European wheat varieties (N = 199) was evaluated under controlled conditions in 2016 and 2017. A split-plot design was used to test the effects of high temperature for ten days after flowering. Flowering time, leaf chlorophyll content, the number of productive spikes, grain number, grain weight and grain size were measured, and the senescence process was modeled. Using genotyping data from a 280 K SNP chip, a genome-wide association study was carried out to test the main effect of each SNP and the effect of SNP × treatment interaction. Genotype × treatment interactions were mainly observed for grain traits measured on the main shoots and tillers. We identified 10 QTLs associated with the main effect of at least one trait and seven QTLs associated with the response to post-anthesis heat stress. Of these, two main QTLs associated with the heat tolerance of thousand-kernel weight were identified on chromosomes 4B and 6B. These QTLs will be useful for breeders to improve grain yield in environments where terminal heat stress is likely to occur.

Download Full-text

Heterologous expression of heat stress-responsive AtPLC9 confers heat tolerance in transgenic rice

BMC Plant Biology ◽

10.1186/s12870-020-02709-5 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Yuliang Liu ◽

Xinye Liu ◽

Xue Wang ◽

Kang Gao ◽

Weiwei Qi ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Heat Stress ◽

Transgenic Rice ◽

Heat Tolerance ◽

Calcium Ion ◽

Molecular Breeding ◽

Cereal Crops ◽

Rna Seq ◽

Wild Type ◽

Heterologous Transformation

Abstract Background As global warming becomes increasingly severe, it is urgent that we enhance the heat tolerance of crops. We previously reported that Arabidopsis thaliana PHOSPHOINOSITIDE-SPECIFIC PHOSPHOLIPASE C9 (AtPLC9) promotes heat tolerance. Results In this study, we ectopically expressed AtPLC9 in rice to examine its potential to improve heat tolerance in this important crop. Whereas AtPLC9 did not improve rice tolerance to salt, drought or cold, transgenic rice did exhibit greater heat tolerance than the wild type. High-throughput RNA-seq revealed extensive and dynamic transcriptome reprofiling in transgenic plants after heat stress. Moreover, the expression of some transcription factors and calcium ion-related genes showed specific upregulation in transgenic rice after heat stress, which might contribute to the enhanced heat tolerance. Conclusions This study provides preliminary guidance for using AtPLC9 to improve heat tolerance in cereal crops and, more broadly, highlights that heterologous transformation can assist with molecular breeding.

Download Full-text

The Physiological Basis of Improved Heat Tolerance in Selected Emmer-Derived Hexaploid Wheat Genotypes

Frontiers in Plant Science ◽

10.3389/fpls.2021.739246 ◽

2021 ◽

Vol 12 ◽

Author(s):

Smi Ullah ◽

Richard Trethowan ◽

Helen Bramley

Keyword(s):

Heat Stress ◽

Heat Tolerance ◽

Stress Responses ◽

Selection Process ◽

Abiotic Stress Tolerance ◽

Grain Filling ◽

Complex Nature ◽

Physiological Basis ◽

Wheat Genotypes ◽

Short Period

Wheat is sensitive to high-temperature stress with crop development significantly impaired depending on the severity and timing of stress. Various physiological mechanisms have been identified as selection targets for heat tolerance; however, the complex nature of the trait and high genotype × temperature interaction limits the selection process. A three-tiered phenotyping strategy was used to overcome this limitation by using wheat genotypes developed from the ancient domesticated wheat, emmer (Triticum dicoccon Schrank), which was considered to have a wide variation for abiotic stress tolerance. A contrasting pair of emmer-based hexaploid lines (classified as tolerant; G1 and susceptible; G2) developed from a backcross to the same recurrent hexaploid parent was chosen based on heat stress responses in the field and was evaluated under controlled glasshouse conditions. The same pair of contrasting genotypes was also subsequently exposed to a short period of elevated temperature (4 days) at anthesis under field conditions using in-field temperature-controlled chambers. The glasshouse and field-based heat chambers produced comparable results. G1 was consistently better adapted to both extended and short periods of heat stress through slow leaf senescence under heat stress, which extended the grain filling period, increased photosynthetic capacity, increased grain filling rates, and resulted in greater kernel weight and higher yield. The use of a combination of phenotyping methods was effective in identifying heat tolerant materials and the mechanisms involved.

Download Full-text

Heat Stress-Responsive Transcriptome Analysis in the Liver Tissue of Hu Sheep

Genes ◽

10.3390/genes10050395 ◽

2019 ◽

Vol 10 (5) ◽

pp. 395 ◽

Cited By ~ 5

Author(s):

Yaokun Li ◽

Lingxuan Kong ◽

Ming Deng ◽

Zhiquan Lian ◽

Yinru Han ◽

...

Keyword(s):

Heat Stress ◽

Molecular Mechanism ◽

Stress Responses ◽

Animal Health ◽

Transcriptome Profiling ◽

Differentially Expressed ◽

Rna Seq ◽

Heat Stress Response ◽

Ppar Signaling ◽

Hu Sheep

Heat stress has a severe effect on animal health and can reduce the productivity and reproductive efficiency; it is therefore necessary to explore the molecular mechanism involved in heat stress response, which is helpful for the cultivation of an animal breed with resistance to heat stress. However, little research about heat stress-responsive molecular analysis has been reported in sheep. Therefore, in this study, RNA sequencing (RNA-Seq) was used to investigate the transcriptome profiling in the liver of Hu sheep with and without heat stress. In total, we detected 520 and 22 differentially expressed mRNAs and lncRNAs, respectively. The differentially expressed mRNAs were mainly associated with metabolic processes, the regulation of biosynthetic processes, and the regulation of glucocorticoid; additionally, they were significantly enriched in the heat stress related pathways, including the carbon metabolism, the PPAR signaling pathway, and vitamin digestion and absorption. The co-located differentially expressed lncRNA Lnc_001782 might positively influence the expression of the corresponding genes APOA4 and APOA5, exerting co-regulative effects on the liver function. Thus, we made the hypothesis that Lnc_001782, APOA4 and APOA5 might function synergistically to regulate the anti-heat stress ability in Hu sheep. This study provides a catalog of Hu sheep liver mRNAs and lncRNAs, and will contribute to a better understanding of the molecular mechanism underlying heat stress responses.

Download Full-text

Transcriptome analysis of the role of autophagy in plant response to heat stress

PLoS ONE ◽

10.1371/journal.pone.0247783 ◽

2021 ◽

Vol 16 (2) ◽

pp. e0247783

Author(s):

Yan Zhang ◽

Haoxuan Min ◽

Chengchen Shi ◽

Gengshou Xia ◽

Zhibing Lai

Keyword(s):

Gene Expression ◽

Heat Stress ◽

Heat Tolerance ◽

Stress Responses ◽

Critical Role ◽

Plant Response ◽

Wild Type ◽

Altered Expression ◽

Regulated Gene Expression

Autophagy plays a critical role in plant heat tolerance in part by targeting heat-induced nonnative proteins for degradation. Autophagy also regulates metabolism, signaling and other processes and it is less understood how the broad function of autophagy affects plant heat stress responses. To address this issue, we performed transcriptome profiling of Arabidopsis wild-type and autophagy-deficient atg5 mutant in response to heat stress. A large number of differentially expressed genes (DEGs) were identified between wild-type and atg5 mutant even under normal conditions. These DEGs are involved not only in metabolism, hormone signaling, stress responses but also in regulation of nucleotide processing and DNA repair. Intriguingly, we found that heat treatment resulted in more robust changes in gene expression in wild-type than in the atg5 mutant plants. The dampening effect of autophagy deficiency on heat-regulated gene expression was associated with already altered expression of many heat-regulated DEGs prior to heat stress in the atg5 mutant. Altered expression of a large number of genes involved in metabolism and signaling in the autophagy mutant prior to heat stress may affect plant response to heat stress. Furthermore, autophagy played a positive role in the expression of defense- and stress-related genes during the early stage of heat stress responses but had little effect on heat-induced expression of heat shock genes. Taken together, these results indicate that the broad role of autophagy in metabolism, cellular homeostasis and other processes can also potentially affect plant heat stress responses and heat tolerance.

Download Full-text

Genome-wide association studies on heat stress tolerance during grain development in wheat (Triticum aestivum L.)

10.21203/rs.2.20460/v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Jie Guo ◽

Weiping Shi ◽

Jiahui Guo ◽

Linqi Yue ◽

Lei Zhuang ◽

...

Keyword(s):

Heat Stress ◽

Heat Tolerance ◽

Association Studies ◽

Starch Content ◽

Kernel Weight ◽

Genome Wide Association ◽

Phenotypic Traits ◽

Genome Wide Association Studies ◽

Wheat Cultivars ◽

Genome Wide

Abstract BackgroundHeat stress at the late reproductive stages is a common problem encountered in autumn-sown wheat production regions in China with the affected area covering as much as two-thirds of the crop. In order to develop wheat cultivars with heat-tolerance, it is crucial to explore favorable alleles for use in breeding programs.ResultsIn this study, we performed a 90K iSelect SNP genotyping assay on a collection of 207 wheat cultivars subjected to heat stress during grain-fill growth stage in three years (2015-2017). Genotypic analyses of 19 phenotypic traits revealed that heat stress had major impacts on grain weight, size, and quality. Correlation analyses indicated that thousand kernel weight (TKW) was significantly correlated with grain width (GW) and grain perimeter (GP), whereas grain protein content (GPC) was negatively correlated with total starch content (TSC) (P <0.01). We applied heat susceptibility indices (HSI) for different traits to assess heat tolerance. Genome-wide association studies (GWAS) revealed a total of 125 marker-trait associations (MTAs) at 63 SNP loci on 16 chromosomes each accounting for phenotypic variation (R2) of 3.0-21.4%. 17 loci showed significant associations in three environments. The analysis of selective sweeps indicated that RAC875_c19042_2102 (2B), wsnp_Ex_c257_491667 (3B), wsnp_Ex_rep_c101323_86702413 (5A) and BS00061911_51 (7A) were selected between two subpopulations (top 5%).ConclusionsThese four key MTAs detected in the present study are candidates for further genetic dissection and development of molecular markers.

Download Full-text

Transcriptome Analyses Provide Novel Insights into Heat Stress Responses in Chieh-Qua (Benincasa hispida Cogn. var. Chieh-Qua How)

International Journal of Molecular Sciences ◽

10.3390/ijms20040883 ◽

2019 ◽

Vol 20 (4) ◽

pp. 883 ◽

Cited By ~ 7

Author(s):

Min Wang ◽

Biao Jiang ◽

Wenrui Liu ◽

Yu’e Lin ◽

Zhaojun Liang ◽

...

Keyword(s):

Heat Stress ◽

Stress Responses ◽

Cdna Libraries ◽

Rna Seq ◽

Pentatricopeptide Repeat ◽

Negative Effects ◽

Ubiquitin Protein Ligase ◽

Benincasa Hispida ◽

Higher Temperature ◽

Shock Proteins

Temperature rising caused by global warming has imposed significant negative effects on crop qualities and yields. To get the well-known molecular mechanism upon the higher temperature, we carefully analyzed the RNA sequencing-based transcriptomic responses of two contrasting chieh-qua genotypes: A39 (heat-tolerant) and H5 (heat-sensitive). In this study, twelve cDNA libraries generated from A39 and H5 were performed with a transcriptome assay under normal and heat stress conditions, respectively. A total of 8705 differentially expressed genes (DEGs) were detected under normal conditions (3676 up-regulated and 5029 down-regulated) and 1505 genes under heat stress (914 up-regulated and 591 down-regulated), respectively. A significant positive correlation between RNA-Seq data and qRT-PCR results was identified. DEGs related to heat shock proteins (HSPs), ubiquitin-protein ligase, transcriptional factors, and pentatricopeptide repeat-containing proteins were significantly changed after heat stress. Several genes, which encoded HSPs (CL2311.Contig3 and CL6612.Contig2), cytochrome P450 (CL4517.Contig4 and CL683.Contig7), and bHLH TFs (CL914.Contig2 and CL8321.Contig1) were specifically induced after four days of heat stress. DEGs detected in our study between these two contrasting cultivars would provide a novel basis for isolating useful candidate genes of heat stress responses in chieh-qua.

Download Full-text