Dataset Information

Identification of drought tolerant mechanisms in a drought-tolerant maize mutant based on physiological, biochemical and transcriptomic analyses.

ABSTRACT:

Background

Frequently occurring drought stress negatively affects the production of maize worldwide. Numerous efforts have been made to develop drought-tolerant maize lines and to explore drought tolerant mechanisms in maize. However, there is a lack of comparative studies on transcriptomic changes between drought-tolerant and control maize lines.

Results

In the present study, we have developed a drought-tolerant maize mutant (C7-2t) by irradiating the seeds of maize inbred line ChangC7-2 (C7-2) with ⁶⁰Co-γ. Compared to its wild type C7-2, C7-2t exhibited a significantly delayed wilting and higher drought tolerance under both the controlled and field conditions, indicating its high water-holding ability. Transcriptomic profiling was performed to identify differentially expressed genes (DEGs) between C7-2 and C7-2t during drought. As a result, a total of 4552 DEGs were implied in drought tolerance of C7-2 and C7-2t. In particular, the expression of photosynthesis-related genes in C7-2 was inhibited, whereas these genes in C7-2t were almost unaffected under drought. Moreover, a specific set of the DEGs were involved in phenylpropanoid biosynthesis and taurine (hypotaurine) metabolism in C7-2t; these DEGs were enriched in cell components associated with membrane systems and cell wall biosynthesis.

Conclusions

The drought tolerance of C7-2t was largely due to its high water-holding ability, stable photosynthesis (for supporting osmoregulation) and strengthened biosynthesis of cell walls under drought conditions.

SUBMITTER: Zhang Q

PROVIDER: S-EPMC7350183 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Identification of drought tolerant mechanisms in a drought-tolerant maize mutant based on physiological, biochemical and transcriptomic analyses.

Zhang Qinbin Q Liu Hui H Wu Xiaolin X Wang Wei W

BMC plant biology 20200703 1

<h4>Background</h4>Frequently occurring drought stress negatively affects the production of maize worldwide. Numerous efforts have been made to develop drought-tolerant maize lines and to explore drought tolerant mechanisms in maize. However, there is a lack of comparative studies on transcriptomic changes between drought-tolerant and control maize lines.<h4>Results</h4>In the present study, we have developed a drought-tolerant maize mutant (C7-2t) by irradiating the seeds of maize inbred line C ...[more]

PMID: 32620139

Similar Datasets

Project description:Zea mays is an important crop that is sensitive to drought stress, but survival rates and growth status remain strong in some drought-tolerant lines under stress conditions. Under drought conditions, many biological processes, such as photosynthesis, carbohydrate metabolism and energy metabolism, are suppressed, while little is known about how the transcripts of genes respond to drought stress in the genome-wide rang in the seedling stage. In our study, the transcriptome profiles of two maize recombination inbred lines (drought-tolerant RIL70 and drought-sensitive RIL93) were analyzed at different drought stages to elucidate the dynamic mechanisms underlying drought tolerance in maize seedlings during drought conditions. Different numbers of differentially expressed genes presented in the different stages of drought stress in the two RILs, for the numbers of RIL93 vs. RIL70 were: 9 vs. 358, 477 vs. 103, and 5207 vs. 152 respectively in DT1, DT2, and DT5. Gene Ontology enrichment analysis revealed that in the initial drought-stressed stage, the primary differentially expressed genes involved in cell wall biosynthesis and transmembrane transport biological processes were overrepresented in RIL70 compared to RIL93. On the contrary, differentially expressed genes profiles presented at 2 and 5 day-treatments, the primary differentially expressed genes involved in response to stress, protein folding, oxidation-reduction, photosynthesis and carbohydrate metabolism, were overrepresented in RIL93 compared to RIL70. In addition, the transcription of genes encoding key members of the cell cycle and cell division processes were blocked, but ABA- and programmed cell death-related processes responded positively in RIL93. In contrast, the expression of cell cycle genes, ABA- and programmed cell death-related genes was relatively stable in RIL70. The results we obtained supported the working hypothesis that signaling events associated with turgor homeostasis, as established by cell wall biosynthesis regulation- and aquaporin-related genes, responded early in RIL70, which led to more efficient detoxification signaling (response to stress, protein folding, oxidation-reduction) during drought stress. This energy saving response at the early stages of drought should facilitate more cell activity under stress conditions and result in drought tolerance in RIL70.

Project description:Restriction in nutrient acquisition is one of the primary causes for reduced growth and yield in water deficient soils. Sulfur (S) is an important secondary macronutrient that interacts with several stress metabolites to improve performance of food crops under various environmental stresses including drought. Increased S supply influences uptake and distribution of essential nutrients to confer nutritional homeostasis in plants exposed to limited water conditions. The regulation of S metabolism in plants, resulting in synthesis of numerous S-containing compounds, is crucial to the acclimation response to drought stress. Two different experiments were laid out in semi-controlled conditions to investigate the effects of different S sources on physiological and biochemical mechanisms of maize (Zea mays L. cv. P1574). Initially, the rate of S application in maize was optimized in terms of improved biomass and nutrient uptake. The maize seedlings were grown in sandy loam soil fertigated with various doses (0, 15, 30 and 45 kg ha-1) of different S fertilizers viz. K2SO4, FeSO4, CuSO4 and Na2SO4. The optimized S dose of each fertilizer was later tested in second experiment to determine its role in improving drought tolerance of maize plants. A marked effect of S fertilization was observed on biomass accumulation and nutrients uptake in maize. In addition, the optimized doses significantly increased the gas exchange characteristics and activity of antioxidant enzymes to improve yield of maize. Among various S sources, application of K2SO4 resulted in maximum photosynthetic rate (43%), stomatal conductance (98%), transpiration rate (61%) and sub-stomatal conductance (127%) compared to no S supply. Moreover, it also increased catalase, guaiacol peroxidase and superoxide dismutase activities by 55, 87 and 65%, respectively that ultimately improved maize yield by 33% with respect to control under water deficit conditions. These results highlight the importance of S fertilizers that would likely be helpful for farmers to get better yield in water deficient soils.

Project description:Drought stress is the major abiotic factor threatening maize (Zea mays L.) yield globally. Therefore, revealing the molecular mechanisms fundamental to drought tolerance in maize becomes imperative. Herein, we conducted a comprehensive comparative analysis of two maize inbred lines contrasting in drought stress tolerance based on their physiological and proteomic responses at the seedling stage. Our observations showed that divergent stress tolerance mechanisms exist between the two inbred-lines at physiological and proteomic levels, with YE8112 being comparatively more tolerant than MO17 owing to its maintenance of higher relative leaf water and proline contents, greater increase in peroxidase (POD) activity, along with decreased level of lipid peroxidation under stressed conditions. Using an iTRAQ (isobaric tags for relative and absolute quantification)-based method, we identified a total of 721 differentially abundant proteins (DAPs). Amongst these, we fished out five essential sets of drought responsive DAPs, including 13 DAPs specific to YE8112, 107 specific DAPs shared between drought-sensitive and drought-tolerant lines after drought treatment (SD_TD), three DAPs of YE8112 also regulated in SD_TD, 84 DAPs unique to MO17, and five overlapping DAPs between the two inbred lines. The most significantly enriched DAPs in YE8112 were associated with the photosynthesis antenna proteins pathway, whilst those in MO17 were related to C5-branched dibasic acid metabolism and RNA transport pathways. The changes in protein abundance were consistent with the observed physiological characterizations of the two inbred lines. Further, quantitative real-time polymerase chain reaction (qRT-PCR) analysis results confirmed the iTRAQ sequencing data. The higher drought tolerance of YE8112 was attributed to: activation of photosynthesis proteins involved in balancing light capture and utilization; enhanced lipid-metabolism; development of abiotic and biotic cross-tolerance mechanisms; increased cellular detoxification capacity; activation of chaperones that stabilize other proteins against drought-induced denaturation; and reduced synthesis of redundant proteins to help save energy to battle drought stress. These findings provide further insights into the molecular signatures underpinning maize drought stress tolerance.

Dataset Information

Identification of drought tolerant mechanisms in a drought-tolerant maize mutant based on physiological, biochemical and transcriptomic analyses.

Background

Results

Conclusions

Publications

Identification of drought tolerant mechanisms in a drought-tolerant maize mutant based on physiological, biochemical and transcriptomic analyses.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets