scholarly journals Molecular characterization and differential expression reveal functional divergence of stress-responsive enzymes in C4 panicoid models, Setaria italica and Setaria viridis

2019 ◽  
Author(s):  
Mehanathan Muthamilarasan ◽  
Roshan Kumar Singh ◽  
Bonthala Venkata Suresh ◽  
Priya Dulani ◽  
Nagendra Kumar Singh ◽  
...  

AbstractStress-responsive genes regulate the morpho-physiological as well as molecular responses of plants to environmental cues. In addition to known genes, there are several unknown genes underlying stress-responsive machinery. One such machinery is the sophisticated biochemical carbon-concentrating mechanism of the C4 photosynthetic pathway that enables the plants to survive in high temperatures, high light intensities and drought conditions. Despite the importance of C4 photosynthesis, no comprehensive study has been performed to identify and characterize the key enzymes involved in this process among sequenced Poaceae genomes. In the present study, five major classes of enzymes that are reported to play roles in C4 biochemical carbon-concentrating mechanism were identified in sequenced Poaceae genomes with emphasis on the model crops, Setaria italica and S. viridis. Further analysis revealed that segmental and tandem duplications have contributed to the expansion of these gene families. Comparative genome mapping and molecular dating provided insights into their duplication and divergence in the course of evolution. Expression profiling of candidate genes in contrasting S. italica cultivars subjected to abiotic stresses and hormone treatments showed distinct stress-specific upregulation of SiαCaH1, SiβCaH5, SiPEPC2, SiPPDK2, SiMDH8 and SiNADP-ME5 in the tolerant cultivar. Altogether, the study highlights key stress-responsive genes that could serve as potential candidates for elucidating their precise roles in stress tolerance.Key messageComprehensive analysis of stress-responsive gene families in C4 model plants, Setaria italica and S. viridis identified SiαCaH1, SiPEPC2, SiPPDK2, SiMDH8 and SiNADP-ME5 as potential candidates for engineering abiotic stress tolerance.

2009 ◽  
Vol 37 (2) ◽  
pp. 1125-1135 ◽  
Author(s):  
Parinita Agarwal ◽  
Pradeep K. Agarwal ◽  
Arvind J. Joshi ◽  
Sudhir K. Sopory ◽  
Malireddy K. Reddy

2018 ◽  
Author(s):  
Simon M. Dittami ◽  
Erwan Corre ◽  
Loraine Brillet-Guéguen ◽  
Agnieszka P. Lipinska ◽  
Noé Pontoizeau ◽  
...  

AbstractBrown algae are multicellular photosynthetic stramenopiles that colonize marine rocky shores worldwide. Ectocarpus sp. Ec32 has been established as a genomic model for brown algae. Here we present the genome and metabolic network of the closely related species, Ectocarpus subulatus Kützing, which is characterized by high abiotic stress tolerance. Since their separation, both strains show new traces of viral sequences and the activity of large retrotransposons, which may also be related to the expansion of a family of chlorophyll-binding proteins. Further features suspected to contribute to stress tolerance include an expanded family of heat shock proteins, the reduction of genes involved in the production of halogenated defence compounds, and the presence of fewer cell wall polysaccharide-modifying enzymes. Overall, E. subulatus has mainly lost members of gene families down-regulated in low salinities, and conserved those that were up-regulated in the same condition. However, 96% of genes that differed between the two examined Ectocarpus species, as well as all genes under positive selection, were found to encode proteins of unknown function. This underlines the uniqueness of brown algal stress tolerance mechanisms as well as the significance of establishing E. subulatus as a comparative model for future functional studies.


2019 ◽  
Author(s):  
Nirman Nepal ◽  
Jessica P. Yactayo-Chang ◽  
Karina Medina-Jiménez ◽  
Lucia M. Acosta-Gamboa ◽  
María Elena González-Romero ◽  
...  

AbstractMyo-inositol oxygenase (MIOX) is the first enzyme in the inositol route to ascorbate (L-ascorbic acid, AsA, vitamin C). We have previously shown that Arabidopsis plants constitutively expressing MIOX have elevated foliar AsA content and displayed enhanced growth rate, biomass accumulation, and increased tolerance to multiple abiotic stresses. In this work, we used a combination of transcriptomics, chromatography, microscopy, and physiological measurements to gain a deeper understanding of the underlying mechanisms mediating the phenotype of the AtMIOX4 line. Transcritpomic analysis revealed increased expression of genes involved in auxin synthesis, hydrolysis, transport, and metabolism, which are supported by elevated auxin levels both in vitro and in vivo, and confirmed by assays demonstrating their effect on epidermal cell elongation in the AtMIOX4 over-expresser plants. Additionally, we detected up-regulation of transcripts involved in photosynthesis that was validated by increased efficiency of the photosystem II and proton motive force. We also found increased expression of amylase leading to higher intracellular glucose levels. Multiple gene families conferring plants tolerance to cold, water limitation, and heat stresses were found to be elevated in the AtMIOX4 line. Interestingly, the high AsA plants also displayed up-regulation of transcripts and hormones involved in defense including jasmonates, defensin, glucosinolates, and transcription factors that are known to be important for biotic stress tolerance. These results overall indicate that elevated levels of auxin and glucose, and enhanced photosynthetic efficiency in combination with up-regulation of abiotic stresses response genes underly the higher growth rate and abiotic stresses tolerance phenotype of the AtMIOX4 over-expressers.


2018 ◽  
Vol 34 (2) ◽  
pp. 259-265 ◽  
Author(s):  
Hemant B Kardile ◽  
◽  
Vikrant ◽  
Nirmal Kant Sharma ◽  
Ankita Sharma ◽  
...  

Genes ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 23
Author(s):  
Antt Htet Wai ◽  
Muhammad Waseem ◽  
A B M Mahbub Morshed Khan ◽  
Ujjal Kumar Nath ◽  
Do Jin Lee ◽  
...  

Protein disulfide isomerases (PDI) and PDI-like proteins catalyze the formation and isomerization of protein disulfide bonds in the endoplasmic reticulum and prevent the buildup of misfolded proteins under abiotic stress conditions. In the present study, we conducted the first comprehensive genome-wide exploration of the PDI gene family in tomato (Solanum lycopersicum L.). We identified 19 tomato PDI genes that were unevenly distributed on 8 of the 12 tomato chromosomes, with segmental duplications detected for 3 paralogous gene pairs. Expression profiling of the PDI genes revealed that most of them were differentially expressed across different organs and developmental stages of the fruit. Furthermore, most of the PDI genes were highly induced by heat, salt, and abscisic acid (ABA) treatments, while relatively few of the genes were induced by cold and nutrient and water deficit (NWD) stresses. The predominant expression of SlPDI1-1, SlPDI1-3, SlPDI1-4, SlPDI2-1, SlPDI4-1, and SlPDI5-1 in response to abiotic stress and ABA treatment suggested they play regulatory roles in abiotic stress tolerance in tomato in an ABA-dependent manner. Our results provide new insight into the structure and function of PDI genes and will be helpful for the selection of candidate genes involved in fruit development and abiotic stress tolerance in tomato.


2021 ◽  
Vol 22 (13) ◽  
pp. 7235
Author(s):  
Md. Tahjib-Ul-Arif ◽  
Mst. Ishrat Zahan ◽  
Md. Masudul Karim ◽  
Shahin Imran ◽  
Charles T. Hunter ◽  
...  

Several recent studies have shown that citric acid/citrate (CA) can confer abiotic stress tolerance to plants. Exogenous CA application leads to improved growth and yield in crop plants under various abiotic stress conditions. Improved physiological outcomes are associated with higher photosynthetic rates, reduced reactive oxygen species, and better osmoregulation. Application of CA also induces antioxidant defense systems, promotes increased chlorophyll content, and affects secondary metabolism to limit plant growth restrictions under stress. In particular, CA has a major impact on relieving heavy metal stress by promoting precipitation, chelation, and sequestration of metal ions. This review summarizes the mechanisms that mediate CA-regulated changes in plants, primarily CA’s involvement in the control of physiological and molecular processes in plants under abiotic stress conditions. We also review genetic engineering strategies for CA-mediated abiotic stress tolerance. Finally, we propose a model to explain how CA’s position in complex metabolic networks involving the biosynthesis of phytohormones, amino acids, signaling molecules, and other secondary metabolites could explain some of its abiotic stress-ameliorating properties. This review summarizes our current understanding of CA-mediated abiotic stress tolerance and highlights areas where additional research is needed.


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