Faculty Opinions recommendation of Energy state and its control on seed development: starch accumulation is associated with high ATP and steep oxygen gradients within barley grains.

AbstractDevelopment of the highly desiccation-sensitive (recalcitrant) seeds of primarily one species, Avicennia marina, is reviewed and compared with the ontogeny of desiccation-tolerant (orthodox) seeds. A. marina seeds undergo no maturation drying and remain metabolically active throughout development, which grades almost imperceptibly into germination. While PGR control of histodifferentiation is essentially similar to that characterizing desiccation-tolerant seeds, the phase of growth and reserve deposition is characterized by exceedingly high cytokinin levels which, it is proposed, promote a sink for assimilate import. While some starch accumulation does occur, the predominant reserves are soluble sugars which are readily available for the immediate onset of seedling establishment upon shedding. ABA levels are negligible in the embryo tissues during seed maturation, but increase in the pericarp, which imposes a constraint upon germination until these outer coverings are sloughed or otherwise removed. The pattern of proteins synthesized remains qualitatively similar throughout seed development in A. marina, and no LEA proteins are produced. This suggests both that seedling establishment is independent of maturation proteins and that the absence of LEAs and desiccation sensitivity might be causally related. The study on A. marina reveals that for this recalcitrant seed-type, germination per se cannot be defined: rather, it is considered as the continuation of development temporarily constrained by the pericarp ABA levels. This leads to a reexamination of the role of rehydration as key event sensu stricto, in the germination processes in desiccation-tolerant (orthodox) seeds.

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4D WARPING FOR ANALYSING MORPHOLOGICAL CHANGES IN SEED DEVELOPMENT OF BARLEY GRAINS

Proceedings of the Third International Conference on Computer Vision Theory and Applications ◽

10.5220/0001073803350340 ◽

2008 ◽

Keyword(s):

Seed Development ◽

Morphological Changes ◽

Barley Grains

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SDG711 Is Involved in Rice Seed Development through Regulation of Starch Metabolism Gene Expression in Coordination with Other Histone Modifications

Rice ◽

10.1186/s12284-021-00467-y ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Xiaoyun Liu ◽

Junling Luo ◽

Tiantian Li ◽

Huilan Yang ◽

Ping Wang ◽

...

Keyword(s):

Seed Development ◽

Starch Synthesis ◽

Endosperm Development ◽

Starch Accumulation ◽

Body Region ◽

Rice Seed ◽

Normal Seed ◽

Gene Body Region ◽

Metabolism Gene

AbstractSDG711 is a histone H3K27me2/3 transmethylase in rice, a homolog of CLF in Arabidopsis, and plays key roles in regulating flowering time and panicle development. In this work, we investigated the role of SDG711 in rice seed development. Overexpression and downregulation of SDG711 lead to a decrease and increase in the expression level of genes related to starch accumulation, resulting in smaller seeds or even seed abortion. ChIP assay showed that SDG711-mediated H3K27me3 changed significantly in genes related to endosperm development, and SDG711 can directly bind to the gene body region of several starch synthesis genes and amylase genes. In addition, H3K4me3 and H3K9ac modifications also cooperate with H3K27me3 to regulate the development of the endosperm. Our results suggest that the crosstalk between SDG711-mediated H3K27me3 and H3K4me3, and H3K9ac are involved in starch accumulation to control normal seed development.

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SDG711 is Involved in Rice Seed Development Through Regulation of Starch Metabolism Gene Expression in Coordination With Other Histone Modifications

10.21203/rs.3.rs-40037/v1 ◽

2020 ◽

Author(s):

Xiaoyun Liu ◽

Junling Luo ◽

Tiantian Li ◽

Huilan Yang ◽

Ping Wang ◽

...

Keyword(s):

Seed Development ◽

Starch Synthesis ◽

Endosperm Development ◽

Starch Accumulation ◽

Body Region ◽

Rice Seed ◽

Normal Seed ◽

Gene Body Region ◽

Metabolism Gene

Abstract SDG711 is a histone H3K27me2/3 transmethylases in rice, homolog ofCLFin Arabidopsis, that plays key roles in regulating of flowering time and panicle development. In this work, we investigated that the role of SDG711 in rice seed development. Overexpression and down-regulation of SDG711lead to the decrease and increase of the expression level of genes related to starch accumulation, resulting in smaller seed or even seed abortion. ChIP assay showed that SDG711-mediated H3K27me3 changed significantly in genes related to endosperm development and SDG711 can directly bind to the gene body region of several starch synthesis genes and amylase genes. In addition, H3K4me3 and H3K9ac modifications also cooperate with H3K27me3 to regulate the development of endosperm. Our results suggested that the crosstalk of SDG711-mediated H3K27me3 with H3K4me3 and H3K9ac are involved in starch accumulation to control normal seed development.

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Regulation of metabolism: the work-to-rest transition in skeletal muscle

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00512.2015 ◽

2016 ◽

Vol 310 (8) ◽

pp. E633-E642 ◽

Cited By ~ 11

Author(s):

David F. Wilson

Keyword(s):

Skeletal Muscle ◽

Oxidative Phosphorylation ◽

Energy State ◽

Creatine Phosphate ◽

Steady States ◽

Rate Of Change ◽

Similar Time ◽

Oxygen Gradients ◽

Regulation Of Metabolism ◽

Time Courses

The behavior of oxidative phosphorylation predicted by a model for the mechanism and kinetics of cytochrome c oxidase is compared with the experimentally observed behavior during the work-to-rest transition in skeletal muscle. For both experiment and model, when work stops, the increase in creatine phosphate and decrease in creatine and inorganic phosphate concentrations ([CrP], [Cr], and [Pi]) begin immediately. The rate of change for each is maximal and then progressively slows as the increasing energy state ([ATP]/[ADP][Pi]) suppresses the rate of oxidative phosphorylation. The time courses can be reasonably fitted to single exponential curves with similar time constants. The energy state in the working and resting steady states at constant Po2 are dependent on the intramitochondrial [NAD+]/[NADH], mitochondrial content, and size of the creatine pool ([CrP] + [Cr]). The rate of change in [CrP] is linearly correlated with [CrP] and with [Pi] and [Cr]. The time constant for [CrP] increase in the resting and working steady states, and the rate of decrease in oxygen consumption are similarly dependent on the Po2 in the inspired gas (experimental) or tissue Po2 (model). Myoglobin strongly buffers intracellular Po2 below ∼15 torr, truncating the low end of the oxygen distribution in the tissue and suppressing intra- and intermyocyte oxygen gradients. The predictions of the model are consistent with the experimental data throughout the work/rest transition, providing valuable insights into the regulation of cellular and tissue metabolism.

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High-resolution EM study of submicrometer-grained Al-Mg solid solution alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138993 ◽

1995 ◽

Vol 53 ◽

pp. 524-525

Author(s):

Z. Horita ◽

D. J. Smith ◽

M. Furukawa ◽

M. Nemoto ◽

R. Z. Valiev ◽

...

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

High Resolution ◽

Grain Boundaries ◽

Energy State ◽

High Energy ◽

Grain Structure ◽

Boundary Structure ◽

Solid Solution Alloy ◽

Average Grain Size

It is possible to produce metallic materials with submicrometer-grained (SMG) structures by imposing an intense plastic strain under quasi-hydrostatic pressure. Studies using conventional transmission electron microscopy (CTEM) showed that many grain boundaries in the SMG structures appeared diffuse in nature with poorly defined transition zones between individual grains. The implication of the CTEM observations is that the grain boundaries of the SMG structures are in a high energy state, having non-equilibrium character. It is anticipated that high-resolution electron microscopy (HREM) will serve to reveal a precise nature of the grain boundary structure in SMG materials. A recent study on nanocrystalline Ni and Ni3Al showed lattice distortion and dilatations in the vicinity of the grain boundaries. In this study, HREM observations are undertaken to examine the atomic structure of grain boundaries in an SMG Al-based Al-Mg alloy.An Al-3%Mg solid solution alloy was subjected to torsion straining to produce an equiaxed grain structure with an average grain size of ~0.09 μm.

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