The Arabidopsis Tetratricopeptide Repeat-Containing Protein TTL1 Is Required for Osmotic Stress Responses and Abscisic Acid Sensitivity

ABSTRACT The phytohormone abscisic acid (ABA) plays an important role in modulating plant growth, development, and stress responses. In a genetic screen for mutants with altered drought stress responses, we identified an ABA-overly sensitive mutant, the abo1 mutant, which showed a drought-resistant phenotype. The abo1 mutation enhances ABA-induced stomatal closing and increases ABA sensitivity in inhibiting seedling growth. abo1 mutants are more resistant to oxidative stress than the wild type and show reduced levels of transcripts of several stress- or ABA-responsive genes. Interestingly, the mutation also differentially modulates the development and growth of adjacent guard cells. Map-based cloning identified ABO1 as a new allele of ELO2, which encodes a homolog of Saccharomyces cerevisiae Iki3/Elp1/Tot1 and human IκB kinase-associated protein. Iki3/Elp1/Tot1 is the largest subunit of Elongator, a multifunctional complex with roles in transcription elongation, secretion, and tRNA modification. Ecotopic expression of plant ABO1/ELO2 in a tot1/elp1Δ yeast Elongator mutant complements resistance to zymocin, a yeast killer toxin complex, indicating that ABO1/ELO2 substitutes for the toxin-relevant function of yeast Elongator subunit Tot1/Elp1. Our results uncover crucial roles for ABO1/ELO2 in modulating ABA and drought responses in Arabidopsis thaliana.

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Increased Abscisic Acid Sensitivity And Drought Stress By Overexpression of Abscisic Acid Receptors In Arabidopsis Thaliana

10.21203/rs.3.rs-703845/v1 ◽

2021 ◽

Author(s):

Li Qing ◽

Tian Qianqian ◽

Zhang Yue ◽

Niu Mengxue ◽

Yu Xiaoqian ◽

...

Keyword(s):

Abscisic Acid ◽

Drought Stress ◽

Stress Responses ◽

Populus Euphratica ◽

Wild Type ◽

Positive Role ◽

Acid Sensitivity ◽

Cis Acting ◽

Aba Sensitivity ◽

Use Efficiency

Abstract Abscisic acid (ABA) is a key plant hormone that regulates plant growth development and stress response. ABA is recognized and bound by ABA Receptor PYR/PYL/RCAR (referred to as PYLs). However, little is known about the PYLs gene family in Populus euphratica. Here, we identified 12 PYLs in P. euphratica and named PePYL1-12. Phylogenetic analysis divided the 12 PePYLs into three subfamilies. Subcellular localization showed that PePYL2, PePYL4, PePYL5, PePYL6, and PePYL9 were located in the cytoplasm and nucleus, PePYL10 localized in the nucleus. The promoter of 12 PePYLs contains hormones- and abiotic stress-related cis-acting elements. Moreover, ABA and drought significantly up-regulation the expression of PePYL6 and PePYL9. To study the performance of PePYLs under ABA and drought stress, we generated transgenic Arabidopsis plants overexpressing PePYL6 and PePYL9. Compared with wild type, transgenic Arabidopsis enhanced ABA sensitivity during seed germination and root growth, improved water use efficiency and drought resistance. Taken together, our results confirmed that PePYL6 and PePYL9 play a positive role in ABA-mediated stress responses in P. euphratica.

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Ectopic expression of FvWRKY42 , a WRKY transcription factor from the diploid woodland strawberry ( Fragaria vesca ), enhances resistance to powdery mildew, improves osmotic stress resistance, and increases abscisic acid sensitivity in Arabidopsis

Plant Science ◽

10.1016/j.plantsci.2018.07.010 ◽

2018 ◽

Vol 275 ◽

pp. 60-74 ◽

Cited By ~ 18

Author(s):

Wei Wei ◽

Meng-Yuan Cui ◽

Yang Hu ◽

Kuan Gao ◽

Yin-Ge Xie ◽

...

Keyword(s):

Transcription Factor ◽

Abscisic Acid ◽

Powdery Mildew ◽

Osmotic Stress ◽

Stress Resistance ◽

Ectopic Expression ◽

Wrky Transcription Factor ◽

Fragaria Vesca ◽

Acid Sensitivity ◽

Osmotic Stress Resistance

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CaDHN4, a Salt and Cold Stress-Responsive Dehydrin Gene from Pepper Decreases Abscisic Acid Sensitivity in Arabidopsis

International Journal of Molecular Sciences ◽

10.3390/ijms21010026 ◽

2019 ◽

Vol 21 (1) ◽

pp. 26

Author(s):

Hua-feng Zhang ◽

Su-ya Liu ◽

Ji-hui Ma ◽

Xin-ke Wang ◽

Saeed ul Haq ◽

...

Keyword(s):

Abscisic Acid ◽

Salt Stress ◽

Cold Stress ◽

Stress Responses ◽

Electrolyte Leakage ◽

Cellular Localization ◽

Primary Root ◽

Acid Sensitivity ◽

Aba Sensitivity ◽

Dehydrin Gene

Dehydrins play an important role in improving plant resistance to abiotic stresses. In this study, we isolated a dehydrin gene from pepper (Capsicum annuum L.) leaves, designated as CaDHN4. Sub-cellular localization of CaDHN4 was to be found in the nucleus and membrane. To authenticate the function of CaDHN4 in cold- and salt-stress responses and abscisic acid (ABA) sensitivity, we reduced the CaDHN4 expression using virus-induced gene silencing (VIGS), and overexpressed the CaDHN4 in Arabidopsis. We found that silencing of CaDHN4 reduced the growth of pepper seedlings and CaDHN4-silenced plants exhibited more serious wilting, higher electrolyte leakage, and more accumulation of ROS in the leaves compared to pTRV2:00 plants after cold stress, and lower chlorophyll contents and higher electrolyte leakage compared to pTRV2:00 plants under salt stress. However, CaDHN4-overexpressing Arabidopsis plants had higher seed germination rates and post-germination primary root growth, compared to WT plants under salt stress. In response to cold and salt stresses, the CaDHN4-overexpressed Arabidopsis exhibited lower MDA content, and lower relative electrolyte leakage compared to the WT plants. Under ABA treatments, the fresh weight and germination rates of transgenic plants were higher than WT plants. The transgenic Arabidopsis expressing a CaDHN4 promoter displayed a more intense GUS staining than the normal growth conditions under treatment with hormones including ABA, methyl jasmonate (MeJA), and salicylic acid (SA). Our results suggest that CaDHN4 can protect against cold and salt stresses and decrease ABA sensitivity in Arabidopsis.

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Faculty Opinions recommendation of The plant cuticle is required for osmotic stress regulation of abscisic acid biosynthesis and osmotic stress tolerance in Arabidopsis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.11003957.11944056 ◽

2011 ◽

Author(s):

Tapio Palva

Keyword(s):

Abscisic Acid ◽

Osmotic Stress ◽

Stress Tolerance ◽

Plant Cuticle ◽

Acid Biosynthesis ◽

Abscisic Acid Biosynthesis ◽

Stress Regulation ◽

Osmotic Stress Tolerance

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Genome-wide identification of sucrose nonfermenting-1-related protein kinase (SnRK) genes in barley and RNA-seq analyses of their expression in response to abscisic acid treatment

BMC Genomics ◽

10.1186/s12864-021-07601-6 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Zhiwei Chen ◽

Longhua Zhou ◽

Panpan Jiang ◽

Ruiju Lu ◽

Nigel G. Halford ◽

...

Keyword(s):

Abscisic Acid ◽

Gene Family ◽

Stress Responses ◽

Phylogenetic Analyses ◽

Regulatory Elements ◽

Gene Promoters ◽

Related Protein ◽

Rna Seq ◽

Response Elements ◽

Genome Data

Abstract Background Sucrose nonfermenting-1 (SNF1)-related protein kinases (SnRKs) play important roles in regulating metabolism and stress responses in plants, providing a conduit for crosstalk between metabolic and stress signalling, in some cases involving the stress hormone, abscisic acid (ABA). The burgeoning and divergence of the plant gene family has led to the evolution of three subfamilies, SnRK1, SnRK2 and SnRK3, of which SnRK2 and SnRK3 are unique to plants. Therefore, the study of SnRKs in crops may lead to the development of strategies for breeding crop varieties that are more resilient under stress conditions. In the present study, we describe the SnRK gene family of barley (Hordeum vulgare), the widespread cultivation of which can be attributed to its good adaptation to different environments. Results The barley HvSnRK gene family was elucidated in its entirety from publicly-available genome data and found to comprise 50 genes. Phylogenetic analyses assigned six of the genes to the HvSnRK1 subfamily, 10 to HvSnRK2 and 34 to HvSnRK3. The search was validated by applying it to Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) genome data, identifying 50 SnRK genes in rice (four OsSnRK1, 11 OsSnRK2 and 35 OsSnRK3) and 39 in Arabidopsis (three AtSnRK1, 10 AtSnRK2 and 26 AtSnRK3). Specific motifs were identified in the encoded barley proteins, and multiple putative regulatory elements were found in the gene promoters, with light-regulated elements (LRE), ABA response elements (ABRE) and methyl jasmonate response elements (MeJa) the most common. RNA-seq analysis showed that many of the HvSnRK genes responded to ABA, some positively, some negatively and some with complex time-dependent responses. Conclusions The barley HvSnRK gene family is large, comprising 50 members, subdivided into HvSnRK1 (6 members), HvSnRK2 (10 members) and HvSnRK3 (34 members), showing differential positive and negative responses to ABA.

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Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?

Agronomy ◽

10.3390/agronomy11030435 ◽

2021 ◽

Vol 11 (3) ◽

pp. 435

Author(s):

Agnieszka Ludwiczak ◽

Monika Osiak ◽

Stefany Cárdenas-Pérez ◽

Sandra Lubińska-Mielińska ◽

Agnieszka Piernik

Keyword(s):

Osmotic Stress ◽

Stress Responses ◽

Ionic Composition ◽

Degradation Process ◽

Early Growth ◽

Cultivated Plants ◽

C3 Plants ◽

Growth Stages ◽

Crop Species ◽

Ionic Salt

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants.

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