Starch reduction in rice stems due to a lack of OsAGPL1 or OsAPL3 decreases grain yield under low irradiance during ripening and modifies plant architecture

Starch accumulated in rice (Oryza sativa L.) stems before heading as nonstructural carbohydrates (NSCs) is reported to be important for improving and stabilising grain yield. To evaluate the importance of stem starch, we investigated a retrotransposon (Tos17) insertion rice mutant lacking a gene encoding a large subunit of ADP-glucose pyrophosphorylase (AGP) called OsAGPL1 or OsAPL3. The AGP activity and starch contents of the mutant were drastically reduced in the stem (i.e. leaf sheath and culm) but not in the leaf blade or endosperm. This starch reduction in the leaf sheaths of the mutant was complemented by the introduction of wild-type OsAGPL1. These results strongly suggest that OsAGPL1 plays a principal role in stem starch accumulation. Field experimentations spanning 2 years revealed that the mutant plants were shorter than the wild-type plants. Moreover, the tiller number and angle were larger in the mutant plants than the wild-type plants, but the dry weight at heading stage was not different. The grain yield was slightly lower in control plots without shading treatment. However, this difference increased substantially with shading. Therefore, stem starch is indispensable for normal ripening under low irradiance conditions and probably contributes to the maintenance of appropriate plant architecture.

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Suppression of starch synthesis in rice stems splays tiller angle due to gravitropic insensitivity but does not affect yield

Functional Plant Biology ◽

10.1071/fp14159 ◽

2015 ◽

Vol 42 (1) ◽

pp. 31 ◽

Cited By ~ 12

Author(s):

Masaki Okamura ◽

Tatsuro Hirose ◽

Yoichi Hashida ◽

Ryu Ohsugi ◽

Naohiro Aoki

Keyword(s):

Double Mutant ◽

Oryza Sativa L ◽

Starch Content ◽

Large Subunit ◽

Starch Synthesis ◽

Starch Accumulation ◽

Gravitropic Response ◽

Rice Mutant ◽

Matter Production ◽

Tiller Angle

In rice (Oryza sativa L.), tiller angle – defined as the angle between the main culm and its side tillers – is one of the important factors involved in light use efficiency. To clarify the relationship between tiller angle, gravitropism and stem-starch accumulation, we investigated the shoot gravitropic response of a low stem-starch rice mutant which lacks a large subunit of ADP-glucose pyrophosphorylase (AGP), called OsAGPL1 and exhibits relatively spread tiller angle. The insensitive gravitropic response exhibited by the mutant led us to the conclusion that insensitivity of gravitropism caused by stem-starch reduction splayed the tiller angle. Furthermore, since another AGP gene called OsAGPL3 was expressed at considerable levels in graviresponding sites, we generated a double mutant lacking both OsAGPL1 and OsAGPL3. The double mutant exhibited still lower stem-starch content, less sensitive gravitropic response and greater tiller angle spread than the single mutants. This indicated that the expansion of the tiller angle caused by the reduction in starch level was intense according to the extent of the reduction. We found there were no significant differences between the double mutant and wild-type plants in terms of dry matter production. These results provided new insight into the importance of stem-starch accumulation and ideal plant architecture.

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A rice mutant lacking a large subunit of ADP-glucose pyrophosphorylase has drastically reduced starch content in the culm but normal plant morphology and yield

Functional Plant Biology ◽

10.1071/fp12186 ◽

2012 ◽

Vol 39 (12) ◽

pp. 1068 ◽

Cited By ~ 16

Author(s):

Frederick R. Cook ◽

Brendan Fahy ◽

Kay Trafford

Keyword(s):

No Reduction ◽

Oryza Sativa L ◽

Starch Content ◽

Large Subunit ◽

Plant Morphology ◽

Gene Encoding ◽

Rice Mutant ◽

Carbohydrate Storage ◽

Adp Glucose Pyrophosphorylase ◽

Storage Pools

A mutant of rice (Oryza sativa L.) was identified with a Tos17 insertion in Os05g50380, a gene encoding a plastidial large subunit (LSU) of ADP-glucose pyrophosphorylase (AGPase) that was previously called OsAPL3 or OsAGPL1. The insertion prevents the production of a normal transcript. Characterisation of the mutant showed that this LSU is required for 97% of the starch synthesised in the flowering stem (culm), approximately half of the AGPase activity in developing embryos and that it contributes to AGPase activity in the endosperm. Despite the near absence of starch in the culms and reduced starch content in the embryos, the mutant rice plants grow and develop normally, and show no reduction in productivity. The starch content of leaves is increased in the mutant, revealing plasticity in the distribution of photosynthates among different temporary carbohydrate storage pools within the plant.

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Effects of an Autoregulatory Senescence-inhibitor Gene Construct on Nicotiana alata Link and Otto.

HortScience ◽

10.21273/hortsci.33.3.519d ◽

1998 ◽

Vol 33 (3) ◽

pp. 519d-519 ◽

Cited By ~ 4

Author(s):

Kenneth R. Schroeder ◽

Dennis P. Stimart

Keyword(s):

Agrobacterium Tumefaciens ◽

Plant Height ◽

Dry Weight ◽

Nicotiana Alata ◽

Wild Type ◽

Gene Encoding ◽

Delayed Senescence ◽

Gene Construct ◽

Shoot Dry Weight ◽

Inhibitor System

Nicotiana alata Link and Otto. was transformed via Agrobacterium tumefaciens encoding a senescence-specific promoter SAG12 cloned from Arabidopsis thaliana fused to a Agrobacterium tumefaciens gene encoding isopentenyl transferase (IPT) that catalyzes cytokinin synthesis. This was considered an autoregulatory senescence-inhibitor system. In 1996, we reported delayed senescence of intact flowers by 2 to 6 d and delayed leaf senescence of transgenic vs. wild-type N. alata. Further evaluations in 1997 revealed several other interesting effects of the SAG12-IPT gene construct. Measurement of chlorophyll content of mature leaves showed higher levels of both chlorophyll a and b in transgenic material under normal fertilization and truncated fertilization regimes. At 4 to 5 months of age transgenic plants expressed differences in plant height, branching, and dry weight. Plant height was reduced by 3 to 13 cm; branch counts increased 2 to 3 fold; and shoot dry weight increased up to 11 g over wild-type N. alata. These observations indicate the system is not tightly autoregulated and may prove useful to the floriculture industry for producing compact and more floriferous plants.

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Formate-Dependent H2 Production by the Mesophilic Methanogen Methanococcus maripaludis

Applied and Environmental Microbiology ◽

10.1128/aem.01455-08 ◽

2008 ◽

Vol 74 (21) ◽

pp. 6584-6590 ◽

Cited By ~ 53

Author(s):

Boguslaw Lupa ◽

Erik L. Hendrickson ◽

John A. Leigh ◽

William B. Whitman

Keyword(s):

Dry Weight ◽

Maximal Activity ◽

Growth Conditions ◽

H2 Production ◽

Resting Cells ◽

Wild Type ◽

Methanococcus Maripaludis ◽

Gene Encoding ◽

Major Pathway ◽

Key Enzyme

ABSTRACT Methanococcus maripaludis, an H2- and formate-utilizing methanogen, produced H2 at high rates from formate. The rates and kinetics of H2 production depended upon the growth conditions, and H2 availability during growth was a major factor. Specific activities of resting cells grown with formate or H2 were 0.4 to 1.4 Uï¿½mg−1 (dry weight). H2 production in formate-grown cells followed Michaelis-Menten kinetics, and the concentration of formate required for half-maximal activity (Kf ) was 3.6 mM. In contrast, in H2-grown cells this process followed sigmoidal kinetics, and the Kf was 9 mM. A key enzyme for formate-dependent H2 production was formate dehydrogenase, Fdh. H2 production and growth were severely reduced in a mutant containing a deletion of the gene encoding the Fdh1 isozyme, indicating that it was the primary Fdh. In contrast, a mutant containing a deletion of the gene encoding the Fdh2 isozyme possessed near-wild-type activities, indicating that this isozyme did not play a major role. H2 production by a mutant containing a deletion of the coenzyme F420-reducing hydrogenase Fru was also severely reduced, suggesting that the major pathway of H2 production comprised Fdh1 and Fru. Because a Δfru-Δfrc mutant retained 10% of the wild-type activity, an additional pathway is present. Mutants possessing deletions of the gene encoding the F420-dependent methylene-H4MTP dehydrogenase (Mtd) or the H2-forming methylene-H4MTP dehydrogenase (Hmd) also possessed reduced activity, which suggested that this second pathway was comprised of Fdh1-Mtd-Hmd. In contrast to H2 production, the cellular rates of methanogenesis were unaffected in these mutants, which suggested that the observed H2 production was not a direct intermediate of methanogenesis. In conclusion, high rates of formate-dependent H2 production demonstrated the potential of M. maripaludis for the microbial production of H2 from formate.

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Plant architecture and grain yield are regulated by the novel DHHC-type zinc finger protein genes in rice (Oryza sativa L.)

Plant Science ◽

10.1016/j.plantsci.2016.08.015 ◽

2017 ◽

Vol 254 ◽

pp. 12-21 ◽

Cited By ~ 4

Author(s):

Bo Zhou ◽

Jian Zhong Lin ◽

Dan Peng ◽

Yuan Zhu Yang ◽

Ming Guo ◽

...

Keyword(s):

Oryza Sativa ◽

Grain Yield ◽

Zinc Finger ◽

Plant Architecture ◽

Zinc Finger Protein ◽

Oryza Sativa L ◽

The Novel ◽

Finger Protein

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CO2-Responsive CCT Protein interacts with 14-3-3 proteins and controls the expression of starch synthesis-related genes

10.22541/au.161704145.57069338/v1 ◽

2021 ◽

Author(s):

Hiroshi Fukayama ◽

Naoki Shibatani ◽

Hirofumi Miyagawa ◽

Aiko Koudou ◽

Yasuo Yamauchi ◽

...

Keyword(s):

Oryza Sativa L ◽

Large Subunit ◽

Starch Synthesis ◽

Gel Filtration ◽

Parenchyma Cell ◽

Mesophyll Cell ◽

Leaf Sheath ◽

Bimolecular Fluorescence Complementation ◽

Promoter Regions

CO2 responsive CCT protein (CRCT) is a positive regulator of starch synthesis related genes such as ADP-glucose pyrophosphorylase large subunit 1 and starch branching enzyme I particularly in the leaf sheath of rice (Oryza sativa L.). The promoter GUS analysis revealed that CRCT expressed exclusively in the vascular bundle, whereas starch synthesis related genes were expressed in different sites such as mesophyll cell and starch storage parenchyma cell. However, the chromatin immunoprecipitation (ChIP) using a FLAG-CRCT overexpression line and subsequent qPCR analyses showed that the 5’-flanking regions of these starch synthesis-related genes tended to be enriched by ChIP, suggesting that CRCT can bind to the promoter regions of these genes. The monomer of CRCT is 34.2 kDa, however CRCT was detected at 270 kDa via gel filtration chromatography, suggesting that CRCT forms a complex in vivo. Immunoprecipitation and subsequent MS analysis pulled down several 14-3-3-like proteins. A yeast two-hybrid analysis and bimolecular fluorescence complementation assays confirmed the interaction between CRCT and 14-3-3-like proteins. Although there is an inconsistency in the place of expression, this study provide important findings regarding the molecular function of CRCT to control the expression of key starch synthesis-related genes.

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Overexpression of Mannitol-1-Phosphate Dehydrogenase Increases Mannitol Accumulation and Adds Protection Against Chilling Injury in Petunia

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.130.4.605 ◽

2005 ◽

Vol 130 (4) ◽

pp. 605-610 ◽

Cited By ~ 22

Author(s):

Yu-Jen Chiang ◽

C. Stushnoff ◽

A.E. McSay ◽

M.L. Jones ◽

H.J. Bohnert

Keyword(s):

Chilling Stress ◽

Chilling Injury ◽

Dry Weight ◽

Wild Type ◽

Gene Encoding ◽

E Coli ◽

Horticultural Crops ◽

Transgenic Lines ◽

And Control

Petunia ×hybrida (Hook) Vilm. cv. Mitchell was transformed with an E. coli gene encoding mannitol-1-phosphate dehydrogenase (mtlD). Four plant lines that grew on kanamycin and contained the mtlD transgene were identified. Two of these lines contained high levels of mannitol [high-mannitol lines M3 and M8; mean mannitol = 3.39 μmol·g-1 dry weight (DW)] compared to nontransformed wild-type plants (0.86 μmol·g-1 DW), while two lines had mannitol levels similar to wild-type plants (low-mannitol lines M2 and M9; mean mannitol = 1.05 μmol·g-1 DW). Transgenic and control plants were subjected to chilling stress (3 ± 0.5 °C day/0 ± 0.5 °C night, 12-hour photoperiod and 75% relative humidity) to evaluate the role of mannitol in chilling tolerance. Based upon foliage symptoms and membrane leakage after a 3-week chilling treatment, the high-mannitol containing lines, M3 and M8, were more tolerant of chilling stress than the low-mannitol containing transgenic lines, M2 and M9, and wild-type. Under nonchilling conditions mannitol was the only carbohydrate that differed among transgenic lines, but all carbohydrates were present. When subjected to chilling stress, mannitol levels dropped by 75%, sucrose by 52%, and inositol by 54% in the low-mannitol lines (M2 and M9). In M3 and M8, the high-mannitol lines, mannitol levels decreased by 36%, sucrose by 25%, and inositol by 56%, respectively. Raffinose increased 2- to 3-fold in all lines following exposure to low-temperature chilling stress. In the higher mannitol lines only 0.04% to 0.06% of the total osmotic potential generated from all solutes could be attributed to mannitol, thus its action is more like that of an osmoprotectant rather than an osmoregulator. This study demonstrates that metabolic engineering of osmoprotectant synthesis pathways can be used to improve stress tolerance in horticultural crops.

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HIGH-TILLERING AND DWARF 12 regulates photosynthesis and plant architecture by affecting carotenoid biosynthesis in rice

Journal of Experimental Botany ◽

10.1093/jxb/eraa497 ◽

2020 ◽

Author(s):

Hui Zhou ◽

Mai Yang ◽

Lei Zhao ◽

Zuofeng Zhu ◽

Fengxia Liu ◽

...

Keyword(s):

Plant Architecture ◽

Oryza Sativa L ◽

Carotenoid Biosynthesis ◽

Acceptor Site ◽

Wild Type ◽

Amino Acid Deletion ◽

Single Nucleotide ◽

Positional Mapping ◽

Nucleotide Transition ◽

High Tillering

Abstract Photosynthesis and plant architecture are important factors influencing grain yield in rice (Oryza sativa L.). Here, we identified a high-tillering and dwarf 12 (htd12) mutant and analyzed the effects of the HTD12 mutation on these important factors. HTD12 encodes a 15-cis-ζ-carotene isomerase (Z-ISO) belonging to the nitrite and nitric oxide reductase U (NnrU) protein family, as revealed by positional mapping and transformation experiments. Sequence analysis showed that a single nucleotide transition from guanine (G) to adenine (A) in the 3’ acceptor site between the first intron and second exon of HTD12 alters its mRNA splicing in htd12 plants, resulting in a 49-amino acid deletion that affects carotenoid biosynthesis and photosynthesis. In addition, compared with the wild type, htd12 had significantly lower concentrations of ent-2’-epi-5-deoxystrigol (epi-5DS), a native strigolactone, in both roots and root exudates, resulting in an obvious increase in tiller number and decrease in plant height. These findings indicate that HTD12, the rice homolog of Z-ISO, regulates chloroplast development and photosynthesis by functioning in carotenoid biosynthesis, and modulates plant architecture by affecting strigolactone concentrations.

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The Designation of Micronutrients Foliar Application Influence on Rice (Oryza Sativa L. cv. Shiroodi) Yield and Yield Components

10.21203/rs.3.rs-119603/v1 ◽

2020 ◽

Author(s):

Ashkan Daneshtalab Lahijani ◽

Amir abbas Mosavi ◽

Morteza Moballeghi

Keyword(s):

Grain Yield ◽

Yield Components ◽

Foliar Application ◽

Oryza Sativa L ◽

Critical Role ◽

Accurate Determination ◽

Dry Weight ◽

Research Institution ◽

Zn Content ◽

Yield And Yield Components

Abstract Pursuant to micronutrients critical role in the plant nutrition and metabolism, accurate determination of the best term of foliar application as a practical plant nutritional pathway has substantial circumstances in the novel agricultural approaches. In order to properly assess micronutrients liquid fertilizer with commercial name of Rooyesh no and mentioned ingredients (Fe EDTA 0.1%, Zn EDTA 0.05%, B 0.02%, Cu EDTA 0.05%, and Mn EDTA 0.05%) influence on Shiroodi cultivar yield, this investigation implemented in the Iran Rice Research Institution (Amol, Mazandaran) during two consecutive years (2017-2018). This extensive research conducted in the form of RCBD with eight treatments and three independent replications. The treatments were T0 (control), T1 (one foliar application) to T7 (seven foliar applications). The frequent intervals of foliar applications were seven days and the first foliar application done nine days after transplantation. The results revealed that the micronutrients application effect was significant about plant dry weight, grain yield, 1,000 grains yield and harvest index. Also, the interaction of the year and foliar application was significant about seed Zn content, chlorophyll b and 1,000 grains yield. According to statistical data, it can be concluded that T4 with 4257 kg/ha grain yield compare to control yield 3499.1 kg/ha that indicated 20 percentage approximate enhancement about foliar application treatments, four leaf spraying with 2 liters/ 1000 liters of water dosage of micronutrients could affect grain yield and yield components of rice (shiroodi cv.) significantly through increasing the number of tillers/plant, improvement of panicle length and increasing the number of grains/ panicle. The micronutrients supply through leaves is more effective procedure in the field of rice nutrition compare to soil application method due to higher absorption velocity.

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