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Zhang K, Nakamura S, Ohtsubo KI, Mitsui T. Morphological, Molecular Structural and Physicochemical Characterization of Starch Granules Formed in Endosperm of Rice with Ectopic Overexpression of α-Amylase. J Appl Glycosci (1999) 2024; 71:23-32. [PMID: 38799415 PMCID: PMC11116087 DOI: 10.5458/jag.jag.jag-2023_0016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 12/23/2023] [Indexed: 05/29/2024] Open
Abstract
The objective of this study was to characterize the endosperm starch in rice that ectopically overexpressed the α-amylase. Transgenic rice plants, transformed with cauliflower mosaic virus 35S promoter driven AmyI-1 (35S::AmyI-1) and AmyII-4 (35S::AmyII-4), and 10 kDa prolamin promoter driven AmyI-1 (P10::AmyI-1), were cultivated under standard conditions (23 °C, 12 h in the dark/ 26 °C, 12 h in the light), and brown grains were subsequently harvested. Each grain displayed characteristic chalkiness, while electron microanalyzer (EPMA)-SEM images disclosed numerous small pits on the surface of the starch granules, attributable to α-amylase activity. Fluorescence labeling and capillary electrophoresis analysis of starch chain length distribution revealed no significant alterations in the starches of 35S::AmyI-1 and 35S::AmyII-4 transgenic rice compared to the wild-type. Conversely, the extremely short α-glucan chains (DP 2-8) exhibited a dramatic increase in the P10::AmyI-1 starch. Rapid visco-analyzer analysis also identified variations in the chain length distribution of P10::AmyI-1 starch, manifesting as changes in viscosity. Moreover, 1H-NMR analysis uncovered dynamic modifications in the molecular structure of starch in rice grain transformed with P10::AmyI-1, which was found to possess unprecedented structural characteristics.
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Affiliation(s)
- Kuo Zhang
- Graduate School of Science and Technology, Niigata University
| | - Sumiko Nakamura
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences
| | - Ken-ichi Ohtsubo
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences
| | - Toshiaki Mitsui
- Graduate School of Science and Technology, Niigata University
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2
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Chen L, Zhao N, McClements DJ, Hamaker BR, Miao M. Advanced dendritic glucan-derived biomaterials: From molecular structure to versatile applications. Compr Rev Food Sci Food Saf 2023; 22:4107-4146. [PMID: 37350042 DOI: 10.1111/1541-4337.13201] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 05/30/2023] [Accepted: 06/05/2023] [Indexed: 06/24/2023]
Abstract
There is considerable interest in the development of advanced biomaterials with improved or novel functionality for diversified applications. Dendritic glucans, such as phytoglycogen and glycogen, are abundant biomaterials with highly branched three-dimensional globular architectures, which endow them with unique structural and functional attributes, including small size, large specific surface area, high water solubility, low viscosity, high water retention, and the availability of numerous modifiable surface groups. Dendritic glucans can be synthesized by in vivo biocatalysis reactions using glucosyl-1-phosphate as a substrate, which can be obtained from plant, animal, or microbial sources. They can also be synthesized by in vitro methods using sucrose or starch as a substrate, which may be more suitable for large-scale industrial production. The large numbers of hydroxyl groups on the surfaces of dendritic glucan provide a platform for diverse derivatizations, including nonreducing end, hydroxyl functionalization, molecular degradation, and conjugation modifications. Due to their unique physicochemical and functional attributes, dendritic glucans have been widely applied in the food, pharmaceutical, biomedical, cosmetic, and chemical industries. For instance, they have been used as delivery systems, adsorbents, tissue engineering scaffolds, biosensors, and bioelectronic components. This article reviews progress in the design, synthesis, and application of dendritic glucans over the past several decades.
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Affiliation(s)
- Long Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Ningjing Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - David J McClements
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
| | - Bruce R Hamaker
- Whistler Center for Carbohydrate Research, Purdue University, West Lafayette, Indiana, USA
| | - Ming Miao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
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Feng W, Wang Z, Campanella OH, Zhang T, Miao M. Fabrication of phytoglycogen-derived core-shell nanoparticles: Structure and characterizations. Food Chem 2023; 423:136317. [PMID: 37182493 DOI: 10.1016/j.foodchem.2023.136317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 04/12/2023] [Accepted: 05/03/2023] [Indexed: 05/16/2023]
Abstract
The objective of this work was to investigate the fabrication of core-shell nanoparticles using phosphorylase-catalyzed chain extension of phytoglycogen, and to analyze the changes of structure and characterizations in detail. During the glucosylation reaction, the inorganic phosphate increased substantially up to 2.3 mg/mL in the initial 12 h, and then increased incrementally to 2.5 mg/mL at 24 h. The similar to trends was observed for increasing Mw and Rz over time, due to glucosyl transfers on the surface chain to form a corona around the phytoglycogen core with a larger size. Phosphorylase modification increases the percentages of longer chain fractions and the average chain length increased from degree of polymerization (DP) 11.6 to DP 48.2. The modified phytoglycogen exhibited the characteristic of B-type crystalline structure, indicating that the specific core-shell nanoparticle with inner amorphous nature and outer crystalline layer. The above results revealed that the potentiality of enzymatic chain elongation of phytoglycogen to design novel core-shell nanoparticle with tailor-made structure and functionality.
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Affiliation(s)
- Wenjuan Feng
- State Key Laboratory of Food Science & Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China
| | - Ziqi Wang
- State Key Laboratory of Food Science & Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China
| | - Osvaldo H Campanella
- State Key Laboratory of Food Science & Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China; Whistler Center for Carbohydrate Research, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN 47907, United States
| | - Tao Zhang
- State Key Laboratory of Food Science & Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China
| | - Ming Miao
- State Key Laboratory of Food Science & Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
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Suzuki N, Abiko M, Yano H, Koda T, Nishioka A, Fujita N. Effect of Shearing and Heat Milling Treatment Temperature on the Crystallinity, Thermal Properties, and Molecular Structure of Rice Starch. Foods 2023; 12:1041. [PMID: 36900557 PMCID: PMC10001028 DOI: 10.3390/foods12051041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 02/21/2023] [Accepted: 02/27/2023] [Indexed: 03/05/2023] Open
Abstract
Rice flour is produced by various methods for use in the food industry, but little is known about how the structure of starch is affected during rice flour production. In this study, the crystallinity, thermal properties, and structure of starch in rice flour were investigated after treatment with a shearing and heat milling machine (SHMM) at different temperatures (10-150 °C). Both the crystallinity and gelatinization enthalpy of starch showed an inverse relationship with the treatment temperature; rice flour treated with the SHMM at higher temperatures showed lower crystallinity and gelatinization enthalpy than that treated at lower temperatures. Next, the structure of undegraded starch in the SHMM-treated rice flour was analyzed by gel permeation chromatography. A significant reduction in the molecular weight of amylopectin was observed at high treatment temperatures. Chain length distribution analysis showed that the proportion of long chains (degree of polymerization (DP) > 30) in rice flour decreased at temperatures ≥ 30 °C. By contrast, the molecular weight of amylose did not decrease. In summary, the SHMM treatment of rice flour at high temperatures resulted in starch gelatinization, and the amylopectin molecular weight decreased independently, due to the cleavage of amorphous regions connecting the amylopectin clusters.
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Affiliation(s)
- Naoto Suzuki
- Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Science, Akita Prefectural University, Akita City 010-0195, Akita, Japan;
| | - Marin Abiko
- Graduate School of Organic Materials Science, Yamagata University, Yonezawa City 992-8510, Yamagata, Japan; (M.A.); (H.Y.); (T.K.); (A.N.)
| | - Hiroko Yano
- Graduate School of Organic Materials Science, Yamagata University, Yonezawa City 992-8510, Yamagata, Japan; (M.A.); (H.Y.); (T.K.); (A.N.)
| | - Tomonori Koda
- Graduate School of Organic Materials Science, Yamagata University, Yonezawa City 992-8510, Yamagata, Japan; (M.A.); (H.Y.); (T.K.); (A.N.)
| | - Akihiro Nishioka
- Graduate School of Organic Materials Science, Yamagata University, Yonezawa City 992-8510, Yamagata, Japan; (M.A.); (H.Y.); (T.K.); (A.N.)
| | - Naoko Fujita
- Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Science, Akita Prefectural University, Akita City 010-0195, Akita, Japan;
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Hashimoto S, Okada S, Araki-Nakamura S, Ohmae-Shinohara K, Miura K, Kawaguchi H, Ogino C, Kasuga S, Sazuka T. An analysis of sugary endosperm in sorghum: Characterization of mutant phenotypes depending on alleles of the corresponding starch debranching enzyme. FRONTIERS IN PLANT SCIENCE 2023; 14:1114935. [PMID: 36860899 PMCID: PMC9969085 DOI: 10.3389/fpls.2023.1114935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
Sorghum is the fifth most important cereal crop. Here we performed molecular genetic analyses of the 'SUGARY FETERITA' (SUF) variety, which shows typical sugary endosperm traits (e.g., wrinkled seeds, accumulation of soluble sugars, and distorted starch). Positional mapping indicated that the corresponding gene was located on the long arm of chromosome 7. Within the candidate region of 3.4 Mb, a sorghum ortholog for maize Su1 (SbSu) encoding a starch debranching enzyme ISA1 was found. Sequencing analysis of SbSu in SUF uncovered nonsynonymous single nucleotide polymorphisms (SNPs) in the coding region, containing substitutions of highly conserved amino acids. Complementation of the rice sugary-1 (osisa1) mutant line with the SbSu gene recovered the sugary endosperm phenotype. Additionally, analyzing mutants obtained from an EMS-induced mutant panel revealed novel alleles with phenotypes showing less severe wrinkles and higher Brix scores. These results suggested that SbSu was the corresponding gene for the sugary endosperm. Expression profiles of starch synthesis genes during the grain-filling stage demonstrated that a loss-of-function of SbSu affects the expression of most starch synthesis genes and revealed the fine-tuned gene regulation in the starch synthetic pathway in sorghum. Haplotype analysis using 187 diverse accessions from a sorghum panel revealed the haplotype of SUF showing severe phenotype had not been used among the landraces and modern varieties. Thus, weak alleles (showing sweet and less severe wrinkles), such as in the abovementioned EMS-induced mutants, are more valuable for grain sorghum breeding. Our study suggests that more moderate alleles (e.g. produced by genome editing) should be beneficial for improving grain sorghum.
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Affiliation(s)
- Shumpei Hashimoto
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Satoshi Okada
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | | | | | - Kotaro Miura
- Faculty of Bioscience and Biotechnology, Fukui Prefectural University, Fukui, Japan
| | - Hideo Kawaguchi
- Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Chiaki Ogino
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Kobe, Japan
| | - Shigemitsu Kasuga
- Faculty of Agriculture, Education and Research Center of Alpine Field Science, Shinshu University, Minamiminowa, Japan
| | - Takashi Sazuka
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
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6
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Pfister B, Shields JM, Kockmann T, Grossmann J, Abt MR, Stadler M, Zeeman SC. Tuning heterologous glucan biosynthesis in yeast to understand and exploit plant starch diversity. BMC Biol 2022; 20:207. [PMID: 36153520 PMCID: PMC9509603 DOI: 10.1186/s12915-022-01408-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 09/13/2022] [Indexed: 11/30/2022] Open
Abstract
Background Starch, a vital plant-derived polysaccharide comprised of branched glucans, is essential in nutrition and many industrial applications. Starch is often modified post-extraction to alter its structure and enhance its functionality. Targeted metabolic engineering of crops to produce valuable and versatile starches requires knowledge of the relationships between starch biosynthesis, structure, and properties, but systematic studies to obtain this knowledge are difficult to conduct in plants. Here we used Saccharomyces cerevisiae as a testbed to dissect the functions of plant starch biosynthetic enzymes and create diverse starch-like polymers. Results We explored yeast promoters and terminators to tune the expression levels of the starch-biosynthesis machinery from Arabidopsis thaliana. We systematically modulated the expression of each starch synthase (SS) together with a branching enzyme (BE) in yeast. Protein quantification by parallel reaction monitoring (targeted proteomics) revealed unexpected effects of glucan biosynthesis on protein abundances but showed that the anticipated broad range of SS/BE enzyme ratios was maintained during the biosynthetic process. The different SS/BE ratios clearly influenced glucan structure and solubility: The higher the SS/BE ratio, the longer the glucan chains and the more glucans were partitioned into the insoluble fraction. This effect was irrespective of the SS isoform, demonstrating that the elongation/branching ratio controls glucan properties separate from enzyme specificity. Conclusions Our results provide a quantitative framework for the in silico design of improved starch biosynthetic processes in plants. Our study also exemplifies a workflow for the rational tuning of a complex pathway in yeast, starting from the selection and evaluation of expression modules to multi-gene assembly and targeted protein monitoring during the biosynthetic process. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01408-x.
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Fujita N, Miura S, Crofts N. Effects of Various Allelic Combinations of Starch Biosynthetic Genes on the Properties of Endosperm Starch in Rice. RICE (NEW YORK, N.Y.) 2022; 15:24. [PMID: 35438319 PMCID: PMC9018920 DOI: 10.1186/s12284-022-00570-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 04/04/2022] [Indexed: 05/09/2023]
Abstract
Rice endosperm accumulates large amounts of photosynthetic products as insoluble starch within amyloplasts by properly arranging structured, highly branched, large amylopectin molecules, thus avoiding osmotic imbalance. The amount and characteristics of starch directly influence the yield and quality of rice grains, which in turn influence their application and market value. Therefore, understanding how various allelic combinations of starch biosynthetic genes, with different expression levels, affect starch properties is important for the identification of targets for breeding new rice cultivars. Research over the past few decades has revealed the spatiotemporal expression patterns and allelic variants of starch biosynthetic genes, and enhanced our understanding of the specific roles and compensatory functions of individual isozymes of starch biosynthetic enzymes through biochemical analyses of purified enzymes and characterization of japonica rice mutants lacking these enzymes. Furthermore, it has been shown that starch biosynthetic enzymes can mutually and synergistically increase their activities by forming protein complexes. This review focuses on the more recent discoveries made in the last several years. Generation of single and double mutants and/or high-level expression of specific starch synthases (SSs) allowed us to better understand how the starch granule morphology is determined; how the complete absence of SSIIa affects starch structure; why the rice endosperm stores insoluble starch rather than soluble phytoglycogen; how to elevate amylose and resistant starch (RS) content to improve health benefits; and how SS isozymes mutually complement their activities. The introduction of active-type SSIIa and/or high-expression type GBSSI into ss3a ss4b, isa1, be2b, and ss3a be2b japonica rice mutants, with unique starch properties, and analyses of their starch properties are summarized in this review. High-level accumulation of RS is often accompanied by a reduction in grain yield as a trade-off. Backcrossing rice mutants with a high-yielding elite rice cultivar enabled the improvement of agricultural traits, while maintaining high RS levels. Designing starch structures for additional values, breeding and cultivating to increase yield will enable the development of a new type of rice starch that can be used in a wide variety of applications, and that can contribute to food and agricultural industries in the near future.
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Affiliation(s)
- Naoko Fujita
- Department of Biological Production, Akita Prefectural University, Akita, 010-0195 Japan
| | - Satoko Miura
- Department of Biological Production, Akita Prefectural University, Akita, 010-0195 Japan
| | - Naoko Crofts
- Department of Biological Production, Akita Prefectural University, Akita, 010-0195 Japan
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Crofts N, Satoh Y, Miura S, Hosaka Y, Abe M, Fujita N. Active-type starch synthase (SS) IIa from indica rice partially complements the sugary-1 phenotype in japonica rice endosperm. PLANT MOLECULAR BIOLOGY 2022; 108:325-342. [PMID: 34287741 DOI: 10.1007/s11103-021-01161-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 06/03/2021] [Indexed: 05/21/2023]
Abstract
Introduction of higher SSIIa activity to mild-type isa1 mutant by crossing results in restoration of crystallinity, starch granule structure, and production of plump seeds. Isoamylase 1 (ISA1) removes improper α-1, 6 glycosidic branches of amylopectin generated by starch branching enzymes and is essential for the formation of proper amylopectin structure. Rice isa1 (sug-1) mutants in japonica cultivar with less-active starch synthase IIa (SSIIa) and low granule-bound SSI (GBSSI) expression display wrinkled seed phenotype by accumulating water-soluble phytoglycogen instead of insoluble amylopectin. Expression of active SSIIa in transgenic rice produced with a severe-type isa1 mutant accumulated some insoluble glucan with weak B-type crystallinity at the periphery of seeds but their seeds remained wrinkled. To see whether introduction of high levels of SSIIa and/or GBSSI can restore the grain filling of the mild-type sug-1 mutant (EM653), new rice lines (SS2a gbss1L isa1, ss2aL GBSS1 isa1, and SS2a GBSS1 isa1) were generated by crossing japonica isa1 mutant (ss2aL gbss1L isa1) with wild type indica rice (SS2a GBSS1 ISA1). The results showed that SS2a gbss1L isa1 and SS2a GBSS1 isa1 lines generated chalky plump seeds accumulating insoluble amylopectin-like glucans with an increase in DP 13-35, while ss2aL GBSS1 isa1 generated wrinkly seeds and accumulated soluble glucans enriched with DP < 13. Scanning electron microscopic observation of cross-section of the seeds showed that SS2a gbss1L isa1 and SS2a GBSS1 isa1 produced wild type-like polygonal starch granules. These starches showed the A-type crystallinity comparable to the wild type, while the japonica isa1 mutant and the transgenic rice do not show any or little crystallinity, respectively. These results indicate that introduction of higher SSIIa activity can mostly complements the mild-type sug-1 phenotype.
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Affiliation(s)
- Naoko Crofts
- Department of Biological Production, Akita Prefectural University, Akita, Japan
| | - Yoshiki Satoh
- Department of Biological Production, Akita Prefectural University, Akita, Japan
| | - Satoko Miura
- Department of Biological Production, Akita Prefectural University, Akita, Japan
| | - Yuko Hosaka
- Department of Biological Production, Akita Prefectural University, Akita, Japan
| | - Misato Abe
- Department of Biological Production, Akita Prefectural University, Akita, Japan
| | - Naoko Fujita
- Department of Biological Production, Akita Prefectural University, Akita, Japan.
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Nagamatsu S, Wada T, Matsushima R, Fujita N, Miura S, Crofts N, Hosaka Y, Yamaguchi O, Kumamaru T. Mutation in BEIIb mitigates the negative effect of the mutation in ISA1 on grain filling and amyloplast formation in rice. PLANT MOLECULAR BIOLOGY 2022; 108:497-512. [PMID: 35083581 DOI: 10.1007/s11103-022-01242-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 01/11/2022] [Indexed: 05/21/2023]
Abstract
Mutation of the BEIIb gene in an isa1 mutant background mitigates the negative effect of the ISA1 mutation on grain filling, and facilitates recovery of amyloplast formation in rice endosperm. In this study, the effect of branching enzyme IIb and isoamylase 1 deficiency on starch properties was demonstrated using high resistant starch rice lines, Chikushi-kona 85 and EM129. Both lines harbored a mutation in the BEIIb and ISA1 genes and showed no BEIIb and ISA1 activity, implying that both lines are beIIb isa1 double mutants. The amylopectin long chain and apparent amylose content of both mutant lines were higher than those of the wild-type. While both mutants contained loosely packed, round starch grains, a trait specific to beIIb mutants, they also showed collapsed starch grains at the center of the endosperm, a property specific to isa1 mutants. Furthermore, beIIb isa1 double mutant F2 lines derived from a cross between Chikushi-kona 85 and Nishihomare (wild-type cultivar) showed significantly heavier seed weight than the beIIb and isa1 single mutant lines. These results suggest that co-occurrence of beIIb and isa1 mutant alleles in a single genetic background mitigates the negative effect of the isa1 allele on grain filling, and contributes to recovery of the amyloplast formation defect in the isa1 single mutant.
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Affiliation(s)
- Shiro Nagamatsu
- Fukuoka Agriculture and Forestry Research Center, 587 Yoshiki, Chikushino, Fukuoka, 818-8549, Japan.
| | - Takuya Wada
- Fukuoka Agriculture and Forestry Research Center, 587 Yoshiki, Chikushino, Fukuoka, 818-8549, Japan
| | - Ryo Matsushima
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo Kurashiki, Okayama, 710-0046, Japan
| | - Naoko Fujita
- Department of Biological Production, Akita Prefectural University, 241-438 Kaidobata-Nishi Nakano Shimoshinjo, Akita, 010-0195, Japan
| | - Satoko Miura
- Department of Biological Production, Akita Prefectural University, 241-438 Kaidobata-Nishi Nakano Shimoshinjo, Akita, 010-0195, Japan
| | - Naoko Crofts
- Department of Biological Production, Akita Prefectural University, 241-438 Kaidobata-Nishi Nakano Shimoshinjo, Akita, 010-0195, Japan
| | - Yuko Hosaka
- Department of Biological Production, Akita Prefectural University, 241-438 Kaidobata-Nishi Nakano Shimoshinjo, Akita, 010-0195, Japan
| | - Osamu Yamaguchi
- Fukuoka Agriculture and Forestry Research Center, 587 Yoshiki, Chikushino, Fukuoka, 818-8549, Japan
| | - Toshihiro Kumamaru
- Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
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10
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Ida T, Crofts N, Miura S, Matsushima R, Fujita N. Structure and Properties of Starch in Rice Double Mutants Lacking Starch Synthase (SS) IIa and Starch Branching Enzyme (BE) IIb. J Appl Glycosci (1999) 2021; 68:31-39. [PMID: 34429697 PMCID: PMC8367641 DOI: 10.5458/jag.jag.jag-2021_0002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/16/2021] [Indexed: 12/25/2022] Open
Abstract
Starch biosynthetic enzymes form multi-protein complexes consisting of starch synthase (SS) I, SSIIa, and starch branching enzyme (BE) IIb, which synthesize amylopectin clusters. This study analyzed the starch properties in two double mutant rice lines lacking SSIIa and BEIIb, one of which expressed an inactive BEIIb protein. The ss2a be2b lines showed similar or greater seed weight than the be2b lines, and plant growth was not affected. The ss2a line showed increased short amylopectin chains resulting in a lower gelatinization temperature. Starch granule morphology and A-type crystallinity were similar between the ss2a line and the wild type, except for a mild chalky seed phenotype in the ss2a line. However, the starch phenotype of the ss2a be2b lines, which was similar to that of be2b but not ss2a, was characterized by increased long amylopectin chains, abnormal starch granules, and B-type crystallinity. The similarity in phenotype between the ss2a be2b and be2b lines may be attributed to the inability of the be2b mutants to generate short amylopectin branches, which serve as primers for SSIIa. Therefore, the presence or absence of SSIIa hardly affected the amylopectin structure under the be2b background. The amylose content was significantly higher in the ss2a be2b lines than in the be2b lines. Starch crystallinity was greater in ss2a be2b lines than in be2b lines, despite the fact that starch crystallinity is generally negatively correlated with amylose content. This suggests that the formation of a double helix between long amylopectin chains and amylose affects starch crystallinity in the ss2a be2b mutants.
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Affiliation(s)
- Tamami Ida
- 1 Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
| | - Naoko Crofts
- 1 Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
| | - Satoko Miura
- 1 Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
| | - Ryo Matsushima
- 2 Institute of Plant Science and Resources, Okayama University
| | - Naoko Fujita
- 1 Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
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11
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Seung D. Amylose in starch: towards an understanding of biosynthesis, structure and function. THE NEW PHYTOLOGIST 2020; 228:1490-1504. [PMID: 32767769 DOI: 10.1111/nph.16858] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/13/2020] [Indexed: 05/20/2023]
Abstract
Starch granules are composed of two distinct glucose polymers - amylose and amylopectin. Amylose constitutes 5-35% of most natural starches and has a major influence over starch properties in foods. Its synthesis and storage occurs within the semicrystalline amylopectin matrix of starch granules, this poses a great challenge for biochemical and structural analyses. However, the last two decades have seen vast progress in understanding amylose synthesis, including new insights into the action of GRANULE BOUND STARCH SYNTHASE (GBSS), the major glucosyltransferase that synthesises amylose, and the discovery of PROTEIN TARGETING TO STARCH1 (PTST1) that targets GBSS to starch granules. Advances in analytical techniques have resolved the fine structure of amylose, raising new questions on how structure is determined during biosynthesis. Furthermore, the discovery of wild plants that do not produce amylose revives a long-standing question of why starch granules contain amylose, rather than amylopectin alone. Overall, these findings contribute towards a full understanding of amylose biosynthesis, structure and function that will be essential for future approaches to improve starch quality in crops.
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Affiliation(s)
- David Seung
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
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12
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Smith AM, Zeeman SC. Starch: A Flexible, Adaptable Carbon Store Coupled to Plant Growth. ANNUAL REVIEW OF PLANT BIOLOGY 2020; 71:217-245. [PMID: 32075407 DOI: 10.1146/annurev-arplant-050718-100241] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Research in the past decade has uncovered new and surprising information about the pathways of starch synthesis and degradation. This includes the discovery of previously unsuspected protein families required both for processes and for the long-sought mechanism of initiation of starch granules. There is also growing recognition of the central role of leaf starch turnover in making carbon available for growth across the day-night cycle. Sophisticated systems-level control mechanisms involving the circadian clock set rates of nighttime starch mobilization that maintain a steady supply of carbon until dawn and modulate partitioning of photosynthate into starch in the light, optimizing the fraction of assimilated carbon that can be used for growth. These discoveries also uncover complexities: Results from experiments with Arabidopsis leaves in conventional controlled environments are not necessarily applicable to other organs or species or to growth in natural, fluctuating environments.
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Affiliation(s)
| | - Samuel C Zeeman
- Institute of Plant Molecular Biology, ETH Zürich, 8092 Zürich, Switzerland
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13
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Generation of selectable marker-free soft transgenic rice with transparent kernels by downregulation of SSSII-2. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.cj.2019.05.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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14
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Takahashi S, Kumagai Y, Igarashi H, Horimai K, Ito H, Shimada T, Kato Y, Hamada S. Biochemical analysis of a new sugary-type rice mutant, Hemisugary1, carrying a novel allele of the sugary-1 gene. PLANTA 2019; 251:29. [PMID: 31802247 DOI: 10.1007/s00425-019-03321-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 11/29/2019] [Indexed: 06/10/2023]
Abstract
A novel allele of the sugary-1 rice mutant was isolated. The single amino acid change led to isoamylase activity reduction and accumulation of high-molecular-weight phytoglycogen in seeds. A new sugary rice variety with an improved seed appearance has been isolated and designated Hemisugary1. This mutant, which was derived from Japonica-type cultivar Tsugaruroman treated with sodium azide, has about half the isoamylase activity of seeds in the original Tsugaruroman. The mutant also accumulates significant phytoglycogen, albeit approximately 40% of the total phytoglycogen in the existing sugary cultivar Ayunohikari which is defective in its most isoamylase activity. The site of mutation was identified using a re-sequence of the whole genome and a cleaved amplified polymorphic sequence (CAPS) marker. The hemisugary phenotypes of the F2 progeny were entirely consistent with the results of genotyping using the CAPS marker. Segregation analysis of the F2 population showed that the hemisugary phenotype was controlled by a single recessive gene, which was produced by a G → A single nucleotide polymorphism in the sugary-1 gene, resulting in a missense mutation from glycine to aspartic acid at amino acid position 333. Zymogram showed that this amino acid replacement resulted in a decrease in isoamylase activity with a concomitant reduction in the formation of isoamylase complexes. Phytoglycogen molecules from Hemisugary1 seeds were 3.5 times larger and contained more short glucan chains than did Ayunohikari seeds. Our data provide new insights into the relationship between isoamylase structure and phytoglycogen formation.
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Affiliation(s)
- Sumire Takahashi
- Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori, 036-8561, Japan
| | - Yu Kumagai
- Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori, 036-8561, Japan
| | - Hidenari Igarashi
- Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori, 036-8561, Japan
| | - Karin Horimai
- Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori, 036-8561, Japan
| | - Hiroyuki Ito
- Department of Chemical and Biological Engineering, National Institute of Technology, Akita College, 1-1 Iijima-Bunkyo-cho, Akita, 011-8511, Japan
| | - Toru Shimada
- Faculty of Education, Hirosaki University, 1 Bunkyo-cho, Hirosaki, Aomori, 036-8560, Japan
| | - Yoji Kato
- Faculty of Education, Hirosaki University, 1 Bunkyo-cho, Hirosaki, Aomori, 036-8560, Japan
| | - Shigeki Hamada
- Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori, 036-8561, Japan.
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Abstract
Lafora disease is a severe, autosomal recessive, progressive myoclonus epilepsy. The disease usually manifests in previously healthy adolescents, and death commonly occurs within 10 years of symptom onset. Lafora disease is caused by loss-of-function mutations in EPM2A or NHLRC1, which encode laforin and malin, respectively. The absence of either protein results in poorly branched, hyperphosphorylated glycogen, which precipitates, aggregates and accumulates into Lafora bodies. Evidence from Lafora disease genetic mouse models indicates that these intracellular inclusions are a principal driver of neurodegeneration and neurological disease. The integration of current knowledge on the function of laforin-malin as an interacting complex suggests that laforin recruits malin to parts of glycogen molecules where overly long glucose chains are forming, so as to counteract further chain extension. In the absence of either laforin or malin function, long glucose chains in specific glycogen molecules extrude water, form double helices and drive precipitation of those molecules, which over time accumulate into Lafora bodies. In this article, we review the genetic, clinical, pathological and molecular aspects of Lafora disease. We also discuss traditional antiseizure treatments for this condition, as well as exciting therapeutic advances based on the downregulation of brain glycogen synthesis and disease gene replacement.
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16
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Progress in the genetic engineering of cereals to produce essential polyunsaturated fatty acids. J Biotechnol 2018; 284:115-122. [DOI: 10.1016/j.jbiotec.2018.08.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 08/21/2018] [Accepted: 08/21/2018] [Indexed: 01/28/2023]
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17
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Li QF, Huang LC, Chu R, Li J, Jiang MY, Zhang CQ, Fan XL, Yu HX, Gu MH, Liu QQ. Down-Regulation of SSSII-2 Gene Expression Results in Novel Low-Amylose Rice with Soft, Transparent Grains. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:9750-9760. [PMID: 30160954 DOI: 10.1021/acs.jafc.8b02913] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Although soft rice, with low amylose content (AC), has high eating and cooking quality (ECQ), its appearance is poor due to the opaque endosperm. Here, a novel soft rice with low AC but a transparent appearance was generated by knocking-down the expression of SSSII-2, a gene encoding one isoform of soluble starch synthase (SSS). The physicochemical properties of the SSSII-2 RNAi rice are quite different from the control but more like the popular soft rice "Nanjing 46". The taste value assay further demonstrated that the ECQ of SSSII-2 RNAi rice was as high as "Nanjing 46", but only SSSII-2 RNAi rice retained the transparent endosperm under low moisture conditions. Further examination showed that the different morphologies and fine structures of the starch granules may contribute to the specific properties of SSSII-2 RNAi rice. Therefore, SSSII-2 has potential application in future high quality rice breeding programs.
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Affiliation(s)
- Qian-Feng Li
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
- Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education , Yangzhou University , Yangzhou 225009 , China
| | - Li-Chun Huang
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Rui Chu
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Juan Li
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Mei-Yan Jiang
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Chang-Quan Zhang
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
- Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education , Yangzhou University , Yangzhou 225009 , China
| | - Xiao-Lei Fan
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Heng-Xiu Yu
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Ming-Hong Gu
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
| | - Qiao-Quan Liu
- Key Laboratory of Plant Functional Genomics of the Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture , Yangzhou University , Yangzhou 225009 , China
- Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education , Yangzhou University , Yangzhou 225009 , China
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18
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Characterisations of oil-in-water Pickering emulsion stabilized hydrophobic phytoglycogen nanoparticles. Food Hydrocoll 2018. [DOI: 10.1016/j.foodhyd.2017.05.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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19
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Abstract
The starch-rich endosperms of the Poaceae, which includes wild grasses and their domesticated descendents the cereals, have provided humankind and their livestock with the bulk of their daily calories since the dawn of civilization up to the present day. There are currently unprecedented pressures on global food supplies, largely resulting from population growth, loss of agricultural land that is linked to increased urbanization, and climate change. Since cereal yields essentially underpin world food and feed supply, it is critical that we understand the biological factors contributing to crop yields. In particular, it is important to understand the biochemical pathway that is involved in starch biosynthesis, since this pathway is the major yield determinant in the seeds of six out of the top seven crops grown worldwide. This review outlines the critical stages of growth and development of the endosperm tissue in the Poaceae, including discussion of carbon provision to the growing sink tissue. The main body of the review presents a current view of our understanding of storage starch biosynthesis, which occurs inside the amyloplasts of developing endosperms.
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20
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Pathogenesis of Lafora Disease: Transition of Soluble Glycogen to Insoluble Polyglucosan. Int J Mol Sci 2017; 18:ijms18081743. [PMID: 28800070 PMCID: PMC5578133 DOI: 10.3390/ijms18081743] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 08/04/2017] [Accepted: 08/06/2017] [Indexed: 02/07/2023] Open
Abstract
Lafora disease (LD, OMIM #254780) is a rare, recessively inherited neurodegenerative disease with adolescent onset, resulting in progressive myoclonus epilepsy which is fatal usually within ten years of symptom onset. The disease is caused by loss-of-function mutations in either of the two genes EPM2A (laforin) or EPM2B (malin). It characteristically involves the accumulation of insoluble glycogen-derived particles, named Lafora bodies (LBs), which are considered neurotoxic and causative of the disease. The pathogenesis of LD is therefore centred on the question of how insoluble LBs emerge from soluble glycogen. Recent data clearly show that an abnormal glycogen chain length distribution, but neither hyperphosphorylation nor impairment of general autophagy, strictly correlates with glycogen accumulation and the presence of LBs. This review summarizes results obtained with patients, mouse models, and cell lines and consolidates apparent paradoxes in the LD literature. Based on the growing body of evidence, it proposes that LD is predominantly caused by an impairment in chain-length regulation affecting only a small proportion of the cellular glycogen. A better grasp of LD pathogenesis will further develop our understanding of glycogen metabolism and structure. It will also facilitate the development of clinical interventions that appropriately target the underlying cause of LD.
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21
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Affiliation(s)
- Yasunori Nakamura
- Akita Natural Science Laboratory; Tennoh, Katagami, Akita Japan
- Faculty of Bioresource Sciences; Akita Prefectural University; Shimoshinjo-Nakano, Akita Japan
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22
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Crofts N, Sugimoto K, Oitome NF, Nakamura Y, Fujita N. Differences in specificity and compensatory functions among three major starch synthases determine the structure of amylopectin in rice endosperm. PLANT MOLECULAR BIOLOGY 2017; 94:399-417. [PMID: 28466433 DOI: 10.1007/s11103-017-0614-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 04/19/2017] [Indexed: 05/07/2023]
Abstract
The lengths of amylopectin-branched chains are precise and influence the physicochemical properties of starch, which determine starch functionality. Three major isozymes of starch synthases (SSs), SSI, SSII(a), and SSIII(a), are primarily responsible for amylopectin chain elongation in the storage tissues of plants. To date, the majority of reported rice mutants were generated using japonica cultivars, which have almost inactive SSIIa. Although three SSs share some overlapping chain length preferences, whether they complement each other remains unknown due to the absence of suitable genetic combinations of materials. In this study, rice ss1/SS2a/SS3a and SS1/SS2a/ss3a were newly generated, and the chain length distribution patterns of all the possible combinations of presence and absence of SSI, SSIIa, and SSIIIa activities were compared. This study demonstrated that SSIIa can complement most SSI functions that use glucan chains with DP 6-7 to generate DP 8-12 chains but cannot fully compensate for the elongation of DP 16-19 chains. This suggests that SSIIa preferentially elongates outer but not inner chains of amylopectin. In addition, the results revealed that neither SSI nor SSIIIa compensate for SSIIa. Neither SSI nor SSIIa compensate for elongation of DP >30 by SSIIIa. SSIIa could not resolve the pleiotropic increase of SSI caused by the absence of SSIIIa; instead, SSIIa further elongated those branches elongated by SSI. These results revealed compensatory differences among three major SS isozymes responsible for lengths of amylopectin branches.
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Affiliation(s)
- Naoko Crofts
- Department of Biological Production, Akita Prefectural University, 241-438 Shimoshinjo Nakano Kaidobata-Nishi, Akita City, Akita, 010-0195, Japan
- Japan Society for the Promotion of Science (N.C.), Tokyo, Japan
| | - Kyohei Sugimoto
- Department of Biological Production, Akita Prefectural University, 241-438 Shimoshinjo Nakano Kaidobata-Nishi, Akita City, Akita, 010-0195, Japan
| | - Naoko F Oitome
- Department of Biological Production, Akita Prefectural University, 241-438 Shimoshinjo Nakano Kaidobata-Nishi, Akita City, Akita, 010-0195, Japan
| | - Yasunori Nakamura
- Department of Biological Production, Akita Prefectural University, 241-438 Shimoshinjo Nakano Kaidobata-Nishi, Akita City, Akita, 010-0195, Japan
- Akita Natural Science Laboratory, 25-44 Oiwake-Nishi, Tenno, Katagami City, Akita, 010-0101, Japan
| | - Naoko Fujita
- Department of Biological Production, Akita Prefectural University, 241-438 Shimoshinjo Nakano Kaidobata-Nishi, Akita City, Akita, 010-0195, Japan.
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23
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Itoh Y, Crofts N, Abe M, Hosaka Y, Fujita N. Characterization of the endosperm starch and the pleiotropic effects of biosynthetic enzymes on their properties in novel mutant rice lines with high resistant starch and amylose content. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 258:52-60. [PMID: 28330563 DOI: 10.1016/j.plantsci.2017.02.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 01/19/2017] [Accepted: 02/06/2017] [Indexed: 05/07/2023]
Abstract
Resistant starch (RS) is beneficial to human health. In order to reduce the current prevalence of diabetes and obesity, several transgenic and mutant crops containing high RS content are being developed. RS content of steamed rice with starch-branching enzyme (BE)IIb-deficient mutant endosperms is considerably high. To understand the mechanisms of RS synthesis and to increase RS content, we developed novel mutant rice lines by introducing the gene encoding starch synthase (SS)IIa and/or granule-bound starch synthase (GBSS)I from an indica rice cultivar into a japonica rice-based BEIIb-deficient mutant line, be2b. Introduction of SSIIa from an indica rice cultivar produced higher levels of amylopectin chains with degree of polymerization (DP) 11-18 than those in be2b; the extent of the change was slight due to the shortage of donor chains for SSIIa (DP 6-12) owing to BEIIb deficiency. The introduction of GBSSI from an indica rice cultivar significantly increased amylose content (by approximately 10%) in the endosperm starch. RS content of the new mutant lines was the same as or slightly higher than that of the be2b parent line. The relationship linking starch structure, RS content, and starch biosynthetic enzymes in the new mutant lines has also been discussed.
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Affiliation(s)
- Yuuki Itoh
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Naoko Crofts
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Misato Abe
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Yuko Hosaka
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Naoko Fujita
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan.
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24
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Gao Y, Liu C, Li Y, Zhang A, Dong G, Xie L, Zhang B, Ruan B, Hong K, Xue D, Zeng D, Guo L, Qian Q, Gao Z. QTL analysis for chalkiness of rice and fine mapping of a candidate gene for qACE9. RICE (NEW YORK, N.Y.) 2016; 9:41. [PMID: 27549111 PMCID: PMC4993740 DOI: 10.1186/s12284-016-0114-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 08/12/2016] [Indexed: 05/19/2023]
Abstract
BACKGROUND An ideal appearance is of commercial value for rice varieties. Chalkiness is one of the most important appearance quality indicators. Therefore, clarification of the heredity of chalkiness and its molecular mechanisms will contribute to reduction of rice chalkiness. Although a number of QTLs related to chalkiness were mapped, few of them have been cloned so far. RESULTS In this study, using recombinant inbred lines (RILs) of PA64s and 9311, we identified 19 QTLs associated with chalkiness on chromosomes 1, 4, 6, 7, 9 and 12, which accounted for 5.1 to 30.6 % of phenotypic variations. A novel major QTL qACE9 for the area of chalky endosperm (ACE) was detected in Hainan and Hangzhou, both mapped in the overlapping region on chromosome 9. It was further fine mapped to an interval of 22 kb between two insertion-deletion (InDel) markers IND9-4 and IND9-5 using a BC4F2 population. Gene prediction analysis identified five putative genes, among which only one gene (OsAPS1), whose product involved in starch synthesis, was detected two nucleotide substitutions causing amino acid change between the parents. Significant difference was found in apparent amylose content (AAC) between NILqACE9 and 9311. And starch granules were round and loosely packed in NILqACE9 compared with 9311 by scanning electron microscopy (SEM) analysis. CONCLUSIONS OsAPS1 was selected as a novel candidate gene for fine-mapped qACE9. The candidate gene not only plays a critical role during starch synthesis in endosperm, but also determines the area of chalky endosperm in rice. Further cloning of the QTL will facilitate the improvement of quality in hybrid rice.
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Affiliation(s)
- Yang Gao
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China
| | - Chaolei Liu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Yuanyuan Li
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Anpeng Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Guojun Dong
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Lihong Xie
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Bin Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Banpu Ruan
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Kai Hong
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Dawei Xue
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China
| | - Dali Zeng
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Longbiao Guo
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Zhenyu Gao
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China.
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Kaneko K, Sasaki M, Kuribayashi N, Suzuki H, Sasuga Y, Shiraya T, Inomata T, Itoh K, Baslam M, Mitsui T. Proteomic and Glycomic Characterization of Rice Chalky Grains Produced Under Moderate and High-temperature Conditions in Field System. RICE (NEW YORK, N.Y.) 2016; 9:26. [PMID: 27246013 PMCID: PMC4887401 DOI: 10.1186/s12284-016-0100-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 05/11/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Global climate models predict an increase in global mean temperature and a higher frequency of intense heat spikes during this century. Cereals such as rice (Oryza sativa L.) are more susceptible to heat stress, mainly during the gametogenesis and flowering stages. During periods of high temperatures, grain filling often causes serious damage to the grain quality of rice and, therefore, yield losses. While the genes encoding enzymes involved in carbohydrate metabolism of chalky grains have been established, a significant knowledge gap exists in the proteomic and glycomic responses to warm temperatures in situ. Here, we studied the translucent and opaque characters of high temperature stressed chalky grains of 2009 and 2010 (ripening temperatures: 24.4 and 28.0 °C, respectively). RESULTS Appearance of chalky grains of both years showed some resemblance, and the high-temperature stress of 2010 remarkably extended the chalking of grain. Scanning electron microscopic observation showed that round-shaped starch granules with numerous small pits were loosely packed in the opaque part of the chalky grains. Proteomic analyzes of rice chalky grains revealed deregulations in the expression of multiple proteins implicated in diverse metabolic and physiological functions, such as protein synthesis, redox homeostasis, lipid metabolism, and starch biosynthesis and degradation. The glycomic profiling has shown slight differences in chain-length distributions of starches in the grains of 2009-to-2010. However, no significant changes were observed in the chain-length distributions between the translucent and opaque parts of perfect and chalky grains in both years. The glucose and soluble starch contents in opaque parts were increased by the high-temperature stress of 2010, though those in perfect grains were not different regardless of the environmental changes of 2009-to-2010. CONCLUSION Together with previous findings on the increased expression of α-amylases in the endosperm, these results suggested that unusual starch degradation rather than starch synthesis is involved in occurring of chalky grains of rice under the high-temperature stress during grain filling period.
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Affiliation(s)
- Kentaro Kaneko
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Maiko Sasaki
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Nanako Kuribayashi
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Hiromu Suzuki
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Yukiko Sasuga
- Department of Applied Biological Chemistry, Niigata University, Niigata, 950-218, Japan
| | - Takeshi Shiraya
- Department of Applied Biological Chemistry, Niigata University, Niigata, 950-218, Japan
- Present address: Niigata Crop Research Center, Niigata Agricultural Research Institute, Nagaoka, 940-0826, Japan
| | - Takuya Inomata
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Kimiko Itoh
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Marouane Baslam
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan
| | - Toshiaki Mitsui
- Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan.
- Department of Applied Biological Chemistry, Niigata University, Niigata, 950-218, Japan.
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Sawada H, Tsukahara K, Kohno Y, Suzuki K, Nagasawa N, Tamaoki M. Elevated Ozone Deteriorates Grain Quality of Japonica Rice cv. Koshihikari, Even if it Does Not Cause Yield Reduction. RICE (NEW YORK, N.Y.) 2016; 9:7. [PMID: 26910783 PMCID: PMC4766164 DOI: 10.1186/s12284-016-0079-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/16/2016] [Indexed: 05/15/2023]
Abstract
BACKGROUND It is becoming clear that ozone affects not only grain yield but also grain quality in rice. However, the biochemical mechanisms responsible for ozone-induced changes in appearance quality or components are poorly understood. We analyzed appearance quality and starch composition in the rice cultivars "Koshihikari" (japonica) and "Kasalath" (indica) grown under elevated ozone conditions. RESULTS Elevated ozone significantly increased the proportion of immature (mainly chalky) kernels in "Koshihikari" but not in "Kasalath". Scanning electron microscopy of transverse sections of kernels showed that endosperm starch granules of "Koshihikari" ripened under elevated ozone were loosely packed with large spaces and contained irregular rounded granules. Amylose content was increased in "Koshihikari" kernels with ozone exposure, but was unchanged in "Kasalath" kernels. Distribution analysis of amylopectin chain length showed that ozone induces a decrease of long-side chains and alterations of short side-chains in "Koshihikari" kernels. Furthermore, Starch Synthase (SS) IIIa transcript levels in "Koshihikari" caryopses were decreased by elevated ozone. CONCLUSIONS The japonica cultivar "Koshihikari" showed significant deterioration in appearance quality of kernels caused by abnormal starch accumulation due to exposure to ozone. The alteration patterns of amylose and amylopectin in ozone-exposed rice kernels are similar to those in rice kernels harvested from SSIIIa-deficient mutants. These findings suggest that the increase of chalky kernels in ozone-treated "Koshihikari" is partly attributable to the repressed expression of SSIIIa involved in amylopectin side-chain elongation with ozone exposure. Elevated ozone reduced appearance quality in "Koshihikari" although it did not impair starch properties contributing to the eating quality of cooked rice.
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Affiliation(s)
- Hiroko Sawada
- />Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-8506 Japan
- />JSPS Research Fellow, Japan Society for the Promotion of Science, ᅟChiyoda-ku, Tokyo, 102-0083 ᅟJapan
| | - Keita Tsukahara
- />Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-8506 Japan
| | - Yoshihisa Kohno
- />Central Research Institute of Electric Power Industry, Abiko, Chiba 270-1194 Japan
| | - Keitaro Suzuki
- />NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518 Japan
| | - Nobuhiro Nagasawa
- />Department of Agribusiness, Akita Prefectural University, Minami akita-gun, Akita 010-0444 Japan
| | - Masanori Tamaoki
- />Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-8506 Japan
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Pfister B, Sánchez-Ferrer A, Diaz A, Lu K, Otto C, Holler M, Shaik FR, Meier F, Mezzenga R, Zeeman SC. Recreating the synthesis of starch granules in yeast. eLife 2016; 5:e15552. [PMID: 27871361 PMCID: PMC5119888 DOI: 10.7554/elife.15552] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 10/08/2016] [Indexed: 11/13/2022] Open
Abstract
Starch, as the major nutritional component of our staple crops and a feedstock for industry, is a vital plant product. It is composed of glucose polymers that form massive semi-crystalline granules. Its precise structure and composition determine its functionality and thus applications; however, there is no versatile model system allowing the relationships between the biosynthetic apparatus, glucan structure and properties to be explored. Here, we expressed the core Arabidopsis starch-biosynthesis pathway in Saccharomyces cerevisiae purged of its endogenous glycogen-metabolic enzymes. Systematic variation of the set of biosynthetic enzymes illustrated how each affects glucan structure and solubility. Expression of the complete set resulted in dense, insoluble granules with a starch-like semi-crystalline organization, demonstrating that this system indeed simulates starch biosynthesis. Thus, the yeast system has the potential to accelerate starch research and help create a holistic understanding of starch granule biosynthesis, providing a basis for the targeted biotechnological improvement of crops.
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Affiliation(s)
| | | | - Ana Diaz
- Paul Scherrer Institut, Villigen, Switzerland
| | - Kuanjen Lu
- Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Caroline Otto
- Department of Biology, ETH Zürich, Zürich, Switzerland
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Abstract
Starch-rich crops form the basis of our nutrition, but plants have still to yield all their secrets as to how they make this vital substance. Great progress has been made by studying both crop and model systems, and we approach the point of knowing the enzymatic machinery responsible for creating the massive, insoluble starch granules found in plant tissues. Here, we summarize our current understanding of these biosynthetic enzymes, highlighting recent progress in elucidating their specific functions. Yet, in many ways we have only scratched the surface: much uncertainty remains about how these components function together and are controlled. We flag-up recent observations suggesting a significant degree of flexibility during the synthesis of starch and that previously unsuspected non-enzymatic proteins may have a role. We conclude that starch research is not yet a mature subject and that novel experimental and theoretical approaches will be important to advance the field.
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Affiliation(s)
- Barbara Pfister
- Department of Biology, ETH Zurich, 8092, Zurich, Switzerland
| | - Samuel C Zeeman
- Department of Biology, ETH Zurich, 8092, Zurich, Switzerland.
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Hayashi M, Kodama M, Nakamura Y, Fujita N. Thermal and Pasting Properties, Morphology of Starch Granules, and Crystallinity of Endosperm Starch in the Rice SSI and SSIIIa Double-Mutant. J Appl Glycosci (1999) 2015. [DOI: 10.5458/jag.jag.jag-2015_007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- Mari Hayashi
- Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
| | - Momoko Kodama
- Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
| | - Yasunori Nakamura
- Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
| | - Naoko Fujita
- Laboratory of Plant Physiology, Department of Biological Production, Faculty of Bioresource Sciences, Akita Prefectural University
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Pfister B, Lu KJ, Eicke S, Feil R, Lunn JE, Streb S, Zeeman SC. Genetic Evidence That Chain Length and Branch Point Distributions Are Linked Determinants of Starch Granule Formation in Arabidopsis. PLANT PHYSIOLOGY 2014; 165:1457-1474. [PMID: 24965177 PMCID: PMC4119031 DOI: 10.1104/pp.114.241455] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 06/24/2014] [Indexed: 05/22/2023]
Abstract
The major component of starch is the branched glucan amylopectin. Structural features of amylopectin, such as the branching pattern and the chain length distribution, are thought to be key factors that enable it to form semicrystalline starch granules. We varied both structural parameters by creating Arabidopsis (Arabidopsis thaliana) mutants lacking combinations of starch synthases (SSs) SS1, SS2, and SS3 (to vary chain lengths) and the debranching enzyme ISOAMYLASE1-ISOAMYLASE2 (ISA; to alter branching pattern). The isa mutant accumulates primarily phytoglycogen in leaf mesophyll cells, with only small amounts of starch in other cell types (epidermis and bundle sheath cells). This balance can be significantly shifted by mutating different SSs. Mutation of SS1 promoted starch synthesis, restoring granules in mesophyll cell plastids. Mutation of SS2 decreased starch synthesis, abolishing granules in epidermal and bundle sheath cells. Thus, the types of SSs present affect the crystallinity and thus the solubility of the glucans made, compensating for or compounding the effects of an aberrant branching pattern. Interestingly, ss2 mutant plants contained small amounts of phytoglycogen in addition to aberrant starch. Likewise, ss2ss3 plants contained phytoglycogen, but were almost devoid of glucan despite retaining other SS isoforms. Surprisingly, glucan production was restored in the ss2ss3isa triple mutants, indicating that SS activity in ss2ss3 per se is not limiting but that the isoamylase suppresses glucan accumulation. We conclude that loss of only SSs can cause phytoglycogen production. This is readily degraded by isoamylase and other enzymes so it does not accumulate and was previously unnoticed.
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Affiliation(s)
- Barbara Pfister
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
| | - Kuan-Jen Lu
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
| | - Simona Eicke
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
| | - Regina Feil
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
| | - John E Lunn
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
| | - Sebastian Streb
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
| | - Samuel C Zeeman
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland (B.P., K.-J.L., S.E., S.S., S.C.Z.); andMax Planck Institute for Molecular Plant Physiology, 14476 Potsdam, Germany (R.F., J.E.L.)
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32
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Structure and digestibility of endosperm water-soluble α-glucans from different sugary maize mutants. Food Chem 2014; 143:156-62. [DOI: 10.1016/j.foodchem.2013.07.109] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/13/2013] [Accepted: 07/20/2013] [Indexed: 11/21/2022]
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Li QF, Sun SSM, Liu QQ. Characterization of the spatial and temporal expression of the OsSSII-3 gene encoding a key soluble starch synthase in rice. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2013; 93:3184-90. [PMID: 23681703 DOI: 10.1002/jsfa.6230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 05/02/2013] [Accepted: 05/16/2013] [Indexed: 05/07/2023]
Abstract
BACKGROUND Starch, the major component of rice grain, consists of amylose and amylopectin. SSIIa, a key soluble starch synthase involved in the biosynthesis of rice amylopectin, is a major factor that controls the gelatinization temperature of rice grain. Extensive work has been done and impressive progress has been made in elaborating the function of the gene encoding SSIIa (OsSSII-3). However, the systematic expression analysis of OsSSII-3 is still rare. RESULTS In the present study, we performed a comprehensive expression analysis of OsSSII-3 in both the developing seeds and other tissues of indica rice 9311 by using quantitative real-time PCR. The results showed that the gene was dominantly expressed in the developing seeds. In addition, the promoter sequence of OsSSII-3 was cloned and fused with the GUS reporter gene and its expression was carefully monitored in the transgenic rice. The data from both histochemical and fluorometric analyses showed that the OsSSII-3 promoter was capable of driving the target gene to have an endosperm-specific expression, which may be due to the existing of several endosperm-specific motifs in the promoter, including the -300 elements, AACA motifs and GCN4 motifs. This result was quite consistent with that of the endogenous transcription analysis of OsSSII-3. CONCLUSION This study not only advanced our understanding of the spatial and temporal expression characteristics of OsSSII-3, but also provided a valuable promoter for future application in generating elite rice varieties with high nutritional or medicinal value.
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Affiliation(s)
- Qian-Feng Li
- Key Laboratory of Plant Functional Genomics of Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College, Yangzhou University, Jiangsu, 225009, China; Institute of Plant Molecular Biology and Agri-Biotechnology, Department of Biology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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