scholarly journals Exogenous Application of Low-Concentration Sugar Enhances Brassinosteroid Signaling for Skotomorphogenesis by Promoting BIN2 Degradation

2021 ◽  
Vol 22 (24) ◽  
pp. 13588
Author(s):  
Huachun Sheng ◽  
Shuangxi Zhang ◽  
Yanping Wei ◽  
Shaolin Chen

In plants, seedling growth is subtly controlled by multiple environmental factors and endogenous phytohormones. The cross-talk between sugars and brassinosteroid (BR) signaling is known to regulate plant growth; however, the molecular mechanisms that coordinate hormone-dependent growth responses with exogenous sucrose in plants are incompletely understood. Skotomorphogenesis is a plant growth stage with rapid elongation of the hypocotyls. In the present study, we found that low-concentration sugars could improve skotomorphogenesis in a manner dependent on BR biosynthesis and TOR activation. However, accumulation of BZR1 in bzr1-1D mutant plants partially rescued the defects of skotomorphogenesis induced by the TOR inhibitor AZD, and these etiolated seedlings displayed a normal phenotype like that of wild-type seedlings in response to both sucrose and non-sucrose treatments, thereby indicating that accumulated BZR1 sustained, at least partially, the sucrose-promoted growth of etiolated seedlings (skotomorphogenesis). Moreover, genetic evidence based on a phenotypic analysis of bin2-3bil1bil2 triple-mutant and gain-of-function bin2–1 mutant plant indicated that BIN2 inactivation was conducive to skotomorphogenesis in the dark. Subsequent biochemical and molecular analyses enabled us to confirm that sucrose reduced BIN2 levels via the TOR–S6K2 pathway in etiolated seedlings. Combined with a determination of the cellulose content, our results indicated that sucrose-induced BIN2 degradation led to the accumulation of BZR1 and the enhancement of cellulose synthesis, thereby promoting skotomorphogenesis, and that BIN2 is the converging node that integrates sugar and BR signaling.

2021 ◽  
Vol 118 (30) ◽  
pp. e2021790118
Author(s):  
Tamara Vellosillo ◽  
José R. Dinneny ◽  
Chris R. Somerville ◽  
David W. Ehrhardt

Cellulose is synthesized at the plasma membrane by cellulose synthase (CESA) complexes (CSCs), which are assembled in the Golgi and secreted to the plasma membrane through the trans-Golgi network (TGN) compartment. However, the molecular mechanisms that guide CSCs through the secretory system and deliver them to the plasma membrane are poorly understood. Here, we identified an uncharacterized gene, TRANVIA (TVA), that is transcriptionally coregulated with the CESA genes required for primary cell wall synthesis. The tva mutant exhibits enhanced sensitivity to cellulose synthesis inhibitors; reduced cellulose content; and defective dynamics, density, and secretion of CSCs to the plasma membrane as compared to wild type. TVA is a plant-specific protein of unknown function that is detected in at least two different intracellular compartments: organelles labeled by markers for the TGN and smaller compartments that deliver CSCs to the plasma membrane. Together, our data suggest that TVA promotes trafficking of CSCs to the plasma membrane by facilitating exit from the TGN and/or interaction of CSC secretory vesicles with the plasma membrane.


Molecules ◽  
2021 ◽  
Vol 26 (1) ◽  
pp. 243
Author(s):  
Vivian S. Lin

Continued expansion of the chemical biology toolbox presents many new and diverse opportunities to interrogate the fundamental molecular mechanisms driving complex plant–microbe interactions. This review will examine metabolic labeling with click chemistry reagents and activity-based probes for investigating the impacts of plant-associated microbes on plant growth, metabolism, and immune responses. While the majority of the studies reviewed here used chemical biology approaches to examine the effects of pathogens on plants, chemical biology will also be invaluable in future efforts to investigate mutualistic associations between beneficial microbes and their plant hosts.


Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 370
Author(s):  
Murugesan Chandrasekaran

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts of higher plants which increase the growth and nutrient uptake of host plants. The primary objective was initiated based on analyzing the enormity of optimal effects upon AMF inoculation in a comparative bias between mycorrhizal and non-mycorrhizal plants stipulated on plant biomass and nutrient uptake. Consequently, in accomplishing the above-mentioned objective a vast literature was collected, analyzed, and evaluated to establish a weighted meta-analysis irrespective of AMF species, plant species, family and functional group, and experimental conditions in the context of beneficial effects of AMF. I found a significant increase in the shoot, root, and total biomass by 36.3%, 28.5%, and, 29.7%, respectively. Moreover, mycorrhizal plants significantly increased phosphorus, nitrogen, and potassium uptake by 36.3%, 22.1%, and 18.5%, respectively. Affirmatively upon cross-verification studies, plant growth parameters intensification was accredited to AMF (Rhizophagus fasciculatus followed by Funniliforme mosseae), plants (Triticum aestivum followed by Solanum lycopersicum), and plant functional groups (dicot, herbs, and perennial) were the additional vital important significant predictor variables of plant growth responses. Therefore, the meta-analysis concluded that the emancipated prominent root characteristics, increased morphological traits that eventually help the host plants for efficient phosphorus uptake, thereby enhancing plant biomass. The present analysis can be rationalized for any plant stress and assessment of any microbial agent that contributes to plant growth promotion.


2010 ◽  
Vol 32 (4) ◽  
pp. 419 ◽  
Author(s):  
Xing Teng ◽  
Lei Ba ◽  
Deli Wang ◽  
Ling Wang ◽  
Jushan Liu

Many studies indicated that saliva from herbivores might be involved in plant growth responses when plants have been grazed. However, there is currently no general agreement on whether saliva can affect plant growth. Our aims were to determine the growth response of plants to sheep saliva after defoliation under diverse environmental conditions (different sward structures), and whether the effect of saliva is influenced by time (duration) after its application. We conducted field experiments with clipping treatments and the application of sheep saliva to the damaged parts of tillers to simulate sheep grazing on the perennial grass Leymus chinensis (Trin.) Tzvelev during the early growing seasons. Results demonstrated that clipping with saliva application significantly increased tiller numbers 8 weeks after treatments in comparison with clipping alone. A key finding is that the effect of sheep saliva on plant growth was short-lived. Clipping with saliva application increased leaf weight in the second week, while clipping alone had no effect. Moreover, clipping with saliva application promoted the elongation of new leaves (not the old ones) in the first week whereas clipping alone was ineffective. Results also showed that there were no differences between clipping with saliva application and clipping alone for relative height growth rate and aboveground biomass. Therefore, we concluded that saliva application to clipping treatment would produce an additional effect compared to clipping alone for the plant and the positive effects are time dependent. The additional effects primarily embodied in the individual level of plant, such as the changes of leaf weight and leaf length. Beyond the level, the effects of saliva only produced many more tiller numbers rather than the accumulation of aboveground biomass.


Author(s):  
Wei Cheng ◽  
Xuejing Yu ◽  
Xingguo Wang

Herbaspirillum camelliae WT00C, as a tea-plant endophytic bacterium, not only colonizes specifically in tea plants but also promotes tea-plant growth and selenium enrichment. Different from diazotrophic endophytes H. seropedicae, H. frisingense and H. rubrisubalbicans, H. camelliae WT00C does not display nitrogen-fixing activity. To understand the molecular mechanisms of promoting the growth of tea plant and Se-enrichment, we sequenced and annotated the genome of H. camelliae WT00C. The results showed that the genome was composed of 6,079,821 base pairs with a total of 5,537 genes. The genomic survey also revealed that H. camelliae WT00C was a multifunctional bacterium metabolizing a variety of carbon and nitrogen sources and defending against biotic and abiotic stress. Although this bacterium did not have intact nitrogen-fixing genes, its genome held the genes responsible for indole-3-acetic acid (IAA) biosynthesis, 1-aminocyclopropane-1-carboxylate (ACC) deamination, siderophore synthesis, ammonia formation, urea metabolism, glutathione and selenocompound metabolisms. Biosynthesis of IAA, siderophore, ammonia, urea and ACC deaminase could explain why two bacterial strains promote tea-plant growth and development. Selenocompound metabolism in this bacterium might also benefit tea-plant growth and Se-enrichment. In addition, the genome of H. camelliae also contained a multitude of protein secretion systems T1SS, T3SS, T4SS and T6SS, in which T4SS did not exhibit in other members of the genus Herbaspirillum.


Author(s):  
R. P. Mericle ◽  
L. W. Mericle ◽  
A. E. Smith ◽  
W. F. Campbell ◽  
D. J. Montgomery

Sign in / Sign up

Export Citation Format

Share Document