Plant growth, development, and response to the environment are mediated by a group of small signaling molecules named hormones. Plants regulate hormone response pathways at multiple levels, including ...biosynthesis, metabolism, perception, and signaling. In addition, plants exhibit the unique ability to spatially control hormone distribution. In recent years, multiple transporters have been identified for most of the plant hormones. Here we present an updated snapshot of the known transporters for the hormones abscisic acid, auxin, brassinosteroid, cytokinin, ethylene, gibberellin, jasmonic acid, salicylic acid, and strigolactone. We also describe new findings regarding hormone movement and elaborate on hormone substrate specificity and possible genetic redundancy in hormone transport and distribution. Finally, we discuss subcellular, cell-to-cell, and long-distance hormone movement and local hormone sinks that trigger or prevent hormone-mediated responses.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Carotenoid cleavage oxygenases (CCOs) enzymes play a vital role in plant growth and development through the synthesis of apocarotenoids and their derivative. These chemicals are necessary for flower ...and fruit coloration, as well as the manufacture of plant hormones such as abscisic acid (ABA) and strigolactones, which control a variety of physiological processes. The CCOs gene family has not been characterized in Arachis hypogaea. Genome mining of A. hypogaea identifies 24 AhCCO gene members. The AhCCO gene family was divided into two subgroups based on the recent study of the Arabidopsis thaliana CCO gene family classification system. Twenty-three AhCCO genes, constituting 95.8% of the total, were regulated by 29 miRNAs, underscoring the significance of microRNAs (miRNAs) in governing gene expression in peanuts. AhCCD19 is the only gene that lacks a miRNA target site. The physicochemical characteristics of CCO genes and their molecular weights and isoelectric points were studied further. The genes were then characterized regarding chromosomal distribution, structure, and promoter cis-elements. Light, stress development, drought stress, and hormone responsiveness were discovered to be associated with AhCCO genes, which can be utilized in developing more resilient crops. The investigation also showed the cellular location of the encoded proteins and discovered that the peanut carotenoid oxygenase gene family's expansion was most likely the result of tandem, segmental, and whole-genome duplication events. The localization expresses the abundance of genes mostly in the cytoplasm and chloroplast. Expression analysis shows that AhCCD7 and AhCCD14 genes show the maximum expression in the apical meristem, lateral leaf, and pentafoliate leaf development, while AhNCED9 and AhNCED13 express in response to Aspergillus flavus resistance. This knowledge throws light on the evolutionary history of the AhCCO gene family and may help researchers better understand the molecular processes behind gene duplication occurrences in plants. An integrated synteny study was used to find orthologous carotenoid oxygenase genes in A. hypogaea, whereas Arabidopsis thaliana and Beta vulgaris were used as references for the functional characterization of peanut CCO genes. These studies provide a foundation for future research on the regulation and functions of this gene family. This information provides valuable insights into the genetic regulation of AhCCO genes. This technology could create molecular markers for breeding programs to develop new peanut lines.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Leaf senescence is a highly coordinated, complicated process involving the integration of numerous internal and environmental signals. Salicylic acid (SA) and reactive oxygen species (ROS) are two ...well-defined inducers of leaf senescence whose contents progressively and interdependently increase during leaf senescence via an unknown mechanism. Here, we characterized the transcription factor WRKY75 as a positive regulator of leaf senescence in Arabidopsis thaliana. Knockdown or knockout of WRKY75 delayed age-dependent leaf senescence, while overexpression of WRKY75 accelerated this process. WRKY75 transcription is induced by age, SA, H2O2, and multiple plant hormones. Meanwhile, WRKY75 promotes SA production by inducing the transcription of SA INDUCTION-DEFICIENT2 (SID2) and suppresses H2O2 scavenging, partly by repressing the transcription of CATALASE2 (CAT2). Genetic analysis revealed that the mutation of SID2 or an increase in catalase activity rescued the precocious leaf senescence phenotype evoked by WRKY75 overexpression. Based on these results, we propose a tripartite amplification loop model in which WRKY75, SA, and ROS undergo a gradual but self-sustained rise driven by three interlinking positive feedback loops. This tripartite amplification loop provides a molecular framework connecting upstream signals, such as age and plant hormones, to the downstream regulatory network executed by SA- and H2O2-responsive transcription factors during leaf senescence.
Full text
Available for:
BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Plant hormones and seed germination Miransari, Mohammad; Smith, D.L.
Environmental and experimental botany,
03/2014, Volume:
99
Journal Article
Peer reviewed
•Effects of plant hormones on seed germination with reference to proteomic and molecular biology studies.•The hormonal signaling pathways affecting seed germination.•The distribution of genes in the ...seed regulating different seed activities.•The effects of soil bacteria on the production of plant hormones and establishment of seedlings.•A complete set of details, which may affect seed biology during dormancy and growth.
Seed germination is controlled by a number of mechanisms and is necessary for the growth and development of the embryo, resulting in the eventual production of a new plant. Under unfavorable conditions seeds may become dormant (secondary dormancy) to maintain their germination ability. However, when the conditions are favorable seeds can germinate. There are a number of factors controlling seed germination and dormancy, including plant hormones, which are produced by both plant and soil bacteria. Interactions between plant hormones and plant genes affect seed germination. While the activity of plant hormones is controlled by the expression of genes at different levels, there are plant genes that are activated in the presence of specific plant hormones. Hence, adjusting gene expression may be an effective way to enhance seed germination. The hormonal signaling of IAA and gibberellins has been presented as examples during plant growth and development including seed germination. Some interesting results related to the effects of seed gene distribution on regulating seed activities have also been presented. The role of soil bacteria is also of significance in the production of plant hormones during seed germination, as well as during the establishment of the seedling, by affecting the plant rhizosphere. Most recent findings regarding seed germination and dormancy are reviewed. The significance of plant hormones including abscisic acid, ethylene, gibberellins, auxin, cytokinins and brassinosteroids, with reference to proteomic and molecular biology studies on germination, is also discussed. This review article contains almost a complete set of details, which may affect seed biology during dormancy and growth.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Tillering directly determines the seed production and propagation capacity of clonal plants. However, the molecular mechanisms involved in the tiller development of clonal plants are still not fully ...understood. In this study, we conducted a proteome comparison between the tiller buds and stem node of a multiple-tiller mutant mtn1 (more tillering number 1) and a wild type of centipedegrass. The results showed significant increases of 29.03% and 27.89% in the first and secondary tiller numbers, respectively, in the mtn1 mutant compared to the wild type. The photosynthetic rate increased by 31.44%, while the starch, soluble sugar, and sucrose contents in the tiller buds and stem node showed increases of 13.79%, 39.10%, 97.64%, 37.97%, 55.64%, and 7.68%, respectively, compared to the wild type. Two groups comprising 438 and 589 protein species, respectively, were differentially accumulated in the tiller buds and stem node in the mtn1 mutant. Consistent with the physiological characteristics, sucrose and starch metabolism as well as plant hormone signaling were found to be enriched with differentially abundant proteins (DAPs) in the mtn1 mutant. These results revealed that sugars and plant hormones may play important regulatory roles in the tiller development in centipedegrass. These results expanded our understanding of tiller development in clonal plants.
The color of the pericarp is a crucial characteristic that influences the marketability of papaya fruit. Prior to ripening, normal papaya exhibits a green pericarp, whereas the cultivar 'Zihui' ...displays purple ring spots on the fruit tip, which significantly affects the fruit's visual appeal. To understand the mechanism behind the formation of purple pericarp, this study performed a thorough examination of the transcriptome, plant hormone, and metabolome. Based on the UPLC-ESI-MS/MS system, a total of 35 anthocyanins and 11 plant hormones were identified, with 27 anthocyanins and two plant hormones exhibiting higher levels of abundance in the purple pericarp. In the purple pericarp, 14 anthocyanin synthesis genes were up-regulated, including CHS, CHI, F3H, F3'5'H, F3'H, ANS, OMT, and CYP73A. Additionally, through co-expression network analysis, three MYBs were identified as potential key regulators of anthocyanin synthesis by controlling genes encoding anthocyanin biosynthesis. As a result, we have identified numerous key genes involved in anthocyanin synthesis and developed new insights into how the purple pericarp of papaya is formed.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
As sessile organisms, plants must tolerate various environmental stresses. Plant hormones play vital roles in plant responses to biotic and abiotic stresses. Among these hormones, jasmonic acid (JA) ...and its precursors and derivatives (jasmonates, JAs) play important roles in the mediation of plant responses and defenses to biotic and abiotic stresses and have received extensive research attention. Although some reviews of JAs are available, this review focuses on JAs in the regulation of plant stress responses, as well as JA synthesis, metabolism, and signaling pathways. We summarize recent progress in clarifying the functions and mechanisms of JAs in plant responses to abiotic stresses (drought, cold, salt, heat, and heavy metal toxicity) and biotic stresses (pathogen, insect, and herbivore). Meanwhile, the crosstalk of JA with various other plant hormones regulates the balance between plant growth and defense. Therefore, we review the crosstalk of JAs with other phytohormones, including auxin, gibberellic acid, salicylic acid, brassinosteroid, ethylene, and abscisic acid. Finally, we discuss current issues and future opportunities in research into JAs in plant stress responses.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The present study investigated the effects of several growth regulators on the early growth of banana plants (cv. Grand Naine) at Horticultural Farm, Department of Horticulture and Post-Harvest ...Technology, Institute of Agriculture, Visva-Bharti, Srinikatan, West Bengal, during 2021-2022. Six different combinations of two growth regulators, viz. GA3 (100, 150 and 200 ppm) and NAA (50 and 100 ppm) were used in combination with a control treatment (no growth regulators) in three replications under a randomized block design. According to the final observation taken at 75 DAP, the maximum plant height (56.33 cm), number of leaves/plant (8.47), and pseudostem diameter (25.72 cm) were observed under T5 (GA3 @ 150 ppm + NAA @ 100 ppm). The greatest sizes with respect to total leaf length (36.71 cm), leaf lamina length (28.06 cm) and breadth were also observed under the same treatment. Thus, the performance of banana plants at an early stage was markedly influenced by the application of different growth regulators, and the combination of GA3 @ 150 ppm and NAA @ 100 ppm was the most effective combination of plant growth regulators for improved growth and development of tissue-cultured banana plants.
Carotenoids are an important source of metabolites with regulatory function, which include the plant hormones abscisic acid (ABA) and strigolactones (SLs), and several recently identified growth ...regulators and signaling molecules. These carotenoid-derivatives originate from oxidative breakdown of double bonds in the carotenoid polyene, a common metabolic process that gives rise to diverse carbonyl cleavage-products known as apocarotenoids. Apocarotenoids exert biologically important functions in all taxa. In plants, they are a major regulator of plant growth, development and response to biotic and abiotic environmental stimuli, and mediate plant’s communication with surrounding organisms. In this article, we provide a general overview on the biology of plant apocarotenoids, focusing on ABA, SLs, and recently identified apocarotenoid growth regulators. Following an introduction on carotenoids, we describe plant apocarotenoid biosynthesis, signal transduction, and evolution and summarize their biological functions. Moreover, we discuss the evolution of these intriguing metabolites, which has not been adequately addressed in the literature.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various ...abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light (light quality and light intensity) greatly affect plant photosynthesis and other plant’s morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species (ROS) production, antioxidants, and hormone production.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
