Convergent Starvation Signals and Hormone Crosstalk in Regulating Nutrient Mobilization upon Germination in Cereals

Seed germination is a complex process during which a mature seed resumes metabolic activity to prepare for seedling growth. In this study, we performed a comparative metabolomic analysis of the embryo and endosperm using the community standard lines of three annual Brachypodium species, i.e., B. distachyon (Bd) and B. stacei (Bs) and their natural allotetraploid B. hybridum (BdBs) that has wider ecological range than the other two species. We explored how far the metabolomic impact of allotetraploidization would be observable as over-lapping changes at 4, 12, and 24 h after imbibition (HAI) with water when germination was initiated. Metabolic changes during germination were more prominent in Brachypodium embryos than in the endosperm. The embryo and endosperm metabolomes of Bs and BdBs were similar, and those of Bd were distinctive. The Bs and BdBs embryos showed increased levels of sugars and the tricarboxylic acid cycle compared to Bd, which could have been indicative of better nutrient mobilization from the endosperm. Bs and BdBs also showed higher oxalate levels that could aid nutrient transfer through altered cellular events. In Brachypodium endosperm, the thick cell wall, in addition to starch, has been suggested to be a source of nutrients to the embryo. Metabolites indicative of sugar metabolism in the endosperm of all three species were not prominent, suggesting that mobilization mostly occurred prior to 4 HAI. Hydroxycinnamic and monolignol changes in Bs and BdBs were consistent with cell wall remodeling that arose following the release of nutrients to the respective embryos. Amino acid changes in both the embryo and endosperm were broadly consistent across the species. Taking our data together, the formation of BdBs may have maintained much of the Bs metabolome in both the embryo and endosperm during the early stages of germination. In the embryo, this conserved Bs metabolome appeared to include an elevated sugar metabolism that played a vital role in germination. If these observations are confirmed in the future with more Brachypodium accessions, it would substantiate the dominance of the Bs metabolome in BdBs allotetraploidization and the use of metabolomics to suggest important adaptive changes.

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TAA1-Mediated Auxin Biosynthesis Is Essential for Hormone Crosstalk and Plant Development

Cell ◽

10.1016/j.cell.2008.01.047 ◽

2008 ◽

Vol 133 (1) ◽

pp. 177-191 ◽

Cited By ~ 614

Author(s):

Anna N. Stepanova ◽

Joyce Robertson-Hoyt ◽

Jeonga Yun ◽

Larissa M. Benavente ◽

De-Yu Xie ◽

...

Keyword(s):

Plant Development ◽

Auxin Biosynthesis ◽

Hormone Crosstalk

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Mineral nutrient mobilization by plants from rock: influence of rock type and arbuscular mycorrhiza

Biogeochemistry ◽

10.1007/s10533-015-0092-5 ◽

2015 ◽

Vol 124 (1-3) ◽

pp. 187-203 ◽

Cited By ~ 22

Author(s):

C. Burghelea ◽

D. G. Zaharescu ◽

K. Dontsova ◽

R. Maier ◽

T. Huxman ◽

...

Keyword(s):

Arbuscular Mycorrhiza ◽

Rock Type ◽

Mineral Nutrient ◽

Nutrient Mobilization

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Salinization alters fluxes of bioreactive elements from stream ecosystems across land use

Biogeosciences ◽

10.5194/bg-12-7331-2015 ◽

2015 ◽

Vol 12 (23) ◽

pp. 7331-7347 ◽

Cited By ~ 29

Author(s):

S. Duan ◽

S. S. Kaushal

Keyword(s):

Land Use ◽

Organic Carbon ◽

Fresh Water ◽

Dissolved Inorganic Carbon ◽

Stream Water ◽

Urban Land Use ◽

Stream Ecosystems ◽

Accelerated Weathering ◽

Nutrient Mobilization ◽

Riparian Soils

Abstract. There has been increased salinization of fresh water over decades due to the use of road salt deicers, wastewater discharges, saltwater intrusion, human-accelerated weathering, and groundwater irrigation. Salinization can mobilize bioreactive elements (carbon, nitrogen, phosphorus, sulfur) chemically via ion exchange and/or biologically via influencing of microbial activity. However, the effects of salinization on coupled biogeochemical cycles are still not well understood. We investigated potential impacts of increased salinization on fluxes of bioreactive elements from stream ecosystems (sediments and riparian soils) to overlying stream water and evaluated the implications of percent urban land use on salinization effects. Two-day incubations of sediments and soils with stream and deionized water across three salt levels were conducted at eight routine monitoring stations across a land-use gradient at the Baltimore Ecosystem Study Long-Term Ecological Research (LTER) site in the Chesapeake Bay watershed. Results indicated (1) salinization typically increased sediment releases of labile dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), total dissolved Kjeldahl nitrogen (TKN) (ammonium + ammonia + dissolved organic nitrogen), and sediment transformations of nitrate; (2) salinization generally decreased DOC aromaticity and fluxes of soluble reactive phosphorus from both sediments and soils; (3) the effects of increased salinization on sediment releases of DOC and TKN and DOC quality increased with percentage watershed urbanization. Biogeochemical responses to salinization varied between sediments and riparian soils in releases of DOC and DIC, and nitrate transformations. The differential responses of riparian soils and sediments to increased salinization were likely due to differences in organic matter sources and composition. Our results suggest that short-term increases in salinization can cause releases of significant amounts of labile organic carbon and nitrogen from stream substrates and organic transformations of nitrogen and phosphorus in urban watersheds. Given that salinization of fresh water will increase in the future due to human activities, significant impacts on carbon and nutrient mobilization and water quality should be anticipated.

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Gene expression profiling identifies pathways involved in seeds maturation of Jatropha curcas

10.21203/rs.2.12916/v1 ◽

2019 ◽

Author(s):

Fatemeh Maghuly ◽

Tamas Deak ◽

Klemens Vierlinger ◽

Stephan Pabinger ◽

Hakim Tafer ◽

...

Keyword(s):

Fatty Acid ◽

Seed Development ◽

Jatropha Curcas ◽

Molecular Mechanisms ◽

Seed Quality ◽

Developmental Stages ◽

Seed Maturation ◽

Nutrient Mobilization ◽

Starting Point ◽

Maturation Stages

Abstract Background: Jatropha curcas, a tropical shrub, is a promising biofuel crop, which produces seeds with a high content of oil and protein. To better understand the development of its seeds to improve Jatropha`s agronomic performance, a two-step approach was performed: 1) generation of the entire transcriptome of six different maturation stages of J. curcas seeds using 454-Roche sequencing of a cDNA library, 2) comparison of transcriptional expression levels in six different developmental stages of seeds using a custom Agilent 8x60K oligonucleotide microarray. Results: A total of 793,875 high-quality reads were assembled into 19,841 unique full-length contigs, of which 13,705 could be annotated with Gene Ontology (GO) terms. Microarray data analysis identified 9,111 probes (out of 57,842 probes), which were differentially expressed between the six developmental stages. The expression results were validated for 70 randomly selected putative genes. Result from cluster analyses showed that transcripts related to sucrose, fatty acid, flavonoid, phenylpropanoid, lignin, hormone biosynthesis were over-represented in the early stage, while lipid storage, seed dormancy and maturation in the late stage. Generally, the expression of the most over-represented transcripts decrease in the last stage of seed maturation. Further, expression analyses of different maturation stages of J. curcas seed showed that most changes in transcript abundance occurred between the two last stages, suggesting that the timing of metabolic pathways during seed maturation in J. curcas is in late stages. The co-expression result showed a high degree of connectivity between genes that play essential role in fatty acid biosynthesis and nutrient mobilization. Furthermore, seed development and hormone pathways are significantly well connected. Conclusion: The obtained results revealed DESs regulating important pathways related to seed maturation, which could contribute to understanding the complex regulatory network during seed development. This study provides detailed information on transcription changes during J. curcas seed development and provides a starting point for a genomic survey of seed quality traits. The current results highlighted specific genes and processes relevant to the molecular mechanisms involved in Jatropha seed development, and it is anticipated that this data can be delivered to other Euphorbiaceae species of economic value.

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Nutrient Mobilization and Cycling: Case Studies for Carbon and Nitrogen in Organs of a Legume

Transport and Transfer Process in Plants ◽

10.1016/b978-0-12-734850-6.50045-9 ◽

1976 ◽

pp. 447-462 ◽

Cited By ~ 7

Author(s):

J.S. Pate

Keyword(s):

Case Studies ◽

Nutrient Mobilization ◽

Carbon And Nitrogen

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Contrasting Effects of an Alien Worm on Benthic N Cycling in Muddy and Sandy Sediments

Water ◽

10.3390/w11030465 ◽

2019 ◽

Vol 11 (3) ◽

pp. 465 ◽

Cited By ~ 2

Author(s):

Sara Benelli ◽

Marco Bartoli ◽

Cristina Ribaudo ◽

Elisa Fano

Keyword(s):

Oxygen Demand ◽

Relative Effect ◽

Sediment Oxygen Demand ◽

Inorganic N ◽

N Loss ◽

Nutrient Mobilization ◽

The North ◽

N Fluxes ◽

Muddy Sediments ◽

Sandy Sediments

The North American oligochaete Sparganophilus tamesis is widespread in European freshwaters. Its ecological effects on benthic nitrogen (N) biogeochemistry were studied in two contrasting environments: the organic-rich muddy sediments of the eutrophic Mincio River (Italy) and the organic-poor sandy sediments of the oligotrophic Cazaux-Sanguinet Lake (France). Oxygen and inorganic N fluxes and denitrification rates (IPT) were measured by dark incubation of intact cores with different worm biomass. Sediment oxygen demand and denitrification were higher in muddy than in sandy sediments; however, at the two sites, bioturbation by the oligochaetes stimulated differing microbial O2 and NO3− respiration and NH4+ production. In particular, the relative effect of S. tamesis on sediment metabolism was greater in Cazaux-Sanguinet Lake than in the Mincio River. As a result, S. tamesis favored net N loss in the Mincio River, whereas it increased NH4+ recycling and lowered denitrification efficiency in the Cazaux-Sanguinet Lake. Our results suggest that the effects of S. tamesis on N biogeochemistry might differ depending on local trophic settings. These results have implications for the conservation of isoetids in the French Lake, whose persistence can be menaced by oligochaete-induced nutrient mobilization.

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Fine root decomposition, nutrient mobilization and fungal communities in a pine forest ecosystem

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2015.01.019 ◽

2015 ◽

Vol 83 ◽

pp. 76-83 ◽

Cited By ~ 28

Author(s):

Ang Li ◽

Timothy J. Fahey ◽

Teresa E. Pawlowska ◽

Melany C. Fisk ◽

James Burtis

Keyword(s):

Forest Ecosystem ◽

Fine Root ◽

Pine Forest ◽

Fungal Communities ◽

Root Decomposition ◽

Nutrient Mobilization ◽

Fine Root Decomposition

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Genome-wide association study reveals novel players in defense hormone crosstalk in Arabidopsis

Plant Cell & Environment ◽

10.1111/pce.13357 ◽

2018 ◽

Vol 41 (10) ◽

pp. 2342-2356 ◽

Cited By ~ 19

Author(s):

Silvia Proietti ◽

Lotte Caarls ◽

Silvia Coolen ◽

Johan A. Van Pelt ◽

Saskia C.M. Van Wees ◽

...

Keyword(s):

Association Study ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Hormone Crosstalk ◽

Genome Wide

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Phytosterol Composition of Arachis hypogaea Seeds from Different Maturity Classes

Molecules ◽

10.3390/molecules24010106 ◽

2018 ◽

Vol 24 (1) ◽

pp. 106 ◽

Cited By ~ 2

Author(s):

Wenxu Zhou ◽

William Branch ◽

Lissa Gilliam ◽

Julie Marshall

Keyword(s):

Arachis Hypogaea ◽

Energy Resource ◽

Seed Kernel ◽

Maturation Process ◽

Nutrient Mobilization ◽

Beneficial Effects ◽

Cultivated Peanut ◽

Embryo Heart ◽

The Stability ◽

Phytosterol Composition

The seeds of cultivated peanut, Arachis hypogaea, are an agronomically important crop produced for human nutrition, oilseed and feed stock. Peanut seed is the single most expensive variable input cost and thus producers require seed with excellent performance in terms of germination efficiency. During the maturation process, triglycerides are stored in oil bodies as an energy resource during germination and seedling development. The stability of oil body membranes is essential for nutrient mobilization during germination. This study focused on evaluating the phytosterol composition in seed components including the kernel, embryo (heart), and seed coat or skin. Samples of different maturity classes were analyzed for macronutrient and phytosterol content. The three biosynthetic end products in the phytosterol pathway, β-sitosterol, campesterol and stigmasterol, comprised 82.29%, 86.39% and 94.25% of seed hearts, kernels and seed coats, respectively. Stigmasterol concentration was highest in the seed kernel, providing an excellent source of this sterol known to have beneficial effects on human health. Peanut hearts contained the highest concentration of sterols by mass, potentially providing protection and resources for the developing seedling. The amount of α-tocopherol increases in peanut hearts during the maturation process, providing protection from temperature stress, as well as stability required for seedling vigor. These results suggest that phytosterols may play a significant role in the performance of seeds, and provide a possible explanation for the poor germination efficiency of immature seeds.

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