TY - JOUR A1 - Liu, Qingting A1 - Li, Xiaoping A1 - Fettke, Jörg T1 - Starch granules in Arabidopsis thaliana mesophyll and guard cells show similar morphology but differences in size and number JF - International journal of molecular sciences N2 - Transitory starch granules result from complex carbon turnover and display specific situations during starch synthesis and degradation. The fundamental mechanisms that specify starch granule characteristics, such as granule size, morphology, and the number per chloroplast, are largely unknown. However, transitory starch is found in the various cells of the leaves of Arabidopsis thaliana, but comparative analyses are lacking. Here, we adopted a fast method of laser confocal scanning microscopy to analyze the starch granules in a series of Arabidopsis mutants with altered starch metabolism. This allowed us to separately analyze the starch particles in the mesophyll and in guard cells. In all mutants, the guard cells were always found to contain more but smaller plastidial starch granules than mesophyll cells. The morphological properties of the starch granules, however, were indiscernible or identical in both types of leaf cells. KW - starch granules KW - starch granule number per chloroplast KW - starch morphology KW - mesophyll cell KW - guard cell KW - LCSM KW - Arabidopsis thaliana KW - starch granule initiation KW - starch metabolism Y1 - 2021 U6 - https://doi.org/10.3390/ijms22115666 SN - 1422-0067 SN - 1661-6596 VL - 22 IS - 11 PB - Molecular Diversity Preservation International CY - Basel ER - TY - GEN A1 - Liu, Qingting A1 - Li, Xiaoping A1 - Fettke, Jörg T1 - Starch granules in Arabidopsis thaliana mesophyll and guard cells show similar morphology but differences in size and number T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Transitory starch granules result from complex carbon turnover and display specific situations during starch synthesis and degradation. The fundamental mechanisms that specify starch granule characteristics, such as granule size, morphology, and the number per chloroplast, are largely unknown. However, transitory starch is found in the various cells of the leaves of Arabidopsis thaliana, but comparative analyses are lacking. Here, we adopted a fast method of laser confocal scanning microscopy to analyze the starch granules in a series of Arabidopsis mutants with altered starch metabolism. This allowed us to separately analyze the starch particles in the mesophyll and in guard cells. In all mutants, the guard cells were always found to contain more but smaller plastidial starch granules than mesophyll cells. The morphological properties of the starch granules, however, were indiscernible or identical in both types of leaf cells. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1143 KW - starch granules KW - starch metabolism KW - starch granule initiation KW - starch granule number per chloroplast KW - starch morphology KW - mesophyll cell KW - guard cell KW - LCSM KW - Arabidopsis thaliana Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-511067 SN - 1866-8372 IS - 1143 ER - TY - GEN A1 - Liu, Qingting A1 - Zhou, Yuan A1 - Fettke, Jörg T1 - Starch granule size and morphology of Arabidopsis thaliana starch-related mutants analyzed during diurnal rhythm and development T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Transitory starch plays a central role in the life cycle of plants. Many aspects of this important metabolism remain unknown; however, starch granules provide insight into this persistent metabolic process. Therefore, monitoring alterations in starch granules with high temporal resolution provides one significant avenue to improve understanding. Here, a previously established method that combines LCSM and safranin-O staining for in vivo imaging of transitory starch granules in leaves of Arabidopsis thaliana was employed to demonstrate, for the first time, the alterations in starch granule size and morphology that occur both throughout the day and during leaf aging. Several starch-related mutants were included, which revealed differences among the generated granules. In ptst2 and sex1-8, the starch granules in old leaves were much larger than those in young leaves; however, the typical flattened discoid morphology was maintained. In ss4 and dpe2/phs1/ss4, the morphology of starch granules in young leaves was altered, with a more rounded shape observed. With leaf development, the starch granules became spherical exclusively in dpe2/phs1/ss4. Thus, the presented data provide new insights to contribute to the understanding of starch granule morphogenesis. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1245 KW - starch metabolism KW - starch granule KW - starch granule size KW - starch granule morphology KW - LCSM KW - Arabidopsis thaliana Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-550291 SN - 1866-8372 VL - 26 SP - 1 EP - 9 PB - Universitätsverlag Potsdam CY - Potsdam ET - 19 ER - TY - JOUR A1 - Liu, Qingting A1 - Zhou, Yuan A1 - Fettke, Jörg T1 - Starch granule size and morphology of Arabidopsis thaliana starch-related mutants analyzed during diurnal rhythm and development JF - Molecules : a journal of synthetic chemistry and natural product chemistry / Molecular Diversity Preservation International N2 - Transitory starch plays a central role in the life cycle of plants. Many aspects of this important metabolism remain unknown; however, starch granules provide insight into this persistent metabolic process. Therefore, monitoring alterations in starch granules with high temporal resolution provides one significant avenue to improve understanding. Here, a previously established method that combines LCSM and safranin-O staining for in vivo imaging of transitory starch granules in leaves of Arabidopsis thaliana was employed to demonstrate, for the first time, the alterations in starch granule size and morphology that occur both throughout the day and during leaf aging. Several starch-related mutants were included, which revealed differences among the generated granules. In ptst2 and sex1-8, the starch granules in old leaves were much larger than those in young leaves; however, the typical flattened discoid morphology was maintained. In ss4 and dpe2/phs1/ss4, the morphology of starch granules in young leaves was altered, with a more rounded shape observed. With leaf development, the starch granules became spherical exclusively in dpe2/phs1/ss4. Thus, the presented data provide new insights to contribute to the understanding of starch granule morphogenesis. KW - starch metabolism KW - starch granule KW - starch granule size KW - starch granule morphology KW - LCSM KW - Arabidopsis thaliana Y1 - 2021 U6 - https://doi.org/10.3390/molecules26195859 SN - 1420-3049 VL - 26 SP - 1 EP - 9 PB - MDPI CY - Basel, Schweiz ET - 19 ER - TY - GEN A1 - Li, Xiaoping A1 - Apriyanto, Ardha A1 - Flores Castellanos, Junio A1 - Compart, Julia A1 - Muntaha, Sidratul Nur A1 - Fettke, Jörg T1 - Dpe2/phs1 revealed unique starch metabolism with three distinct phases characterized by different starch granule numbers per chloroplast, allowing insights into the control mechanism of granule number regulation by gene co-regulation and metabolic profiling T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - An Arabidopsis mutant lacking both the cytosolic Disproportionating enzyme 2 (DPE2) and the plastidial glucan Phosphorylase 1 (PHS1) revealed a unique starch metabolism. Dpe2/phs1 has been reported to have only one starch granule number per chloroplast when grown under diurnal rhythm. For this study, we analyzed dpe2/phs1 in details following the mutant development, and found that it showed three distinct periods of granule numbers per chloroplast, while there was no obvious change observed in Col-0. In young plants, the starch granule number was similar to that in Col-0 at first, and then decreased significantly, down to one or no granule per chloroplast, followed by an increase in the granule number. Thus, in dpe2/phs1, control over the starch granule number is impaired, but it is not defective in starch granule initiation. The data also indicate that the granule number is not fixed, and is regulated throughout plant growth. Furthermore, the chloroplasts revealed alterations during these three periods, with a partially strong aberrant morphology in the middle phase. Interestingly, the unique metabolism was perpetuated when starch degradation was further impaired through an additional lack of Isoamylase 3 (ISA3) or Starch excess 4 (SEX4). Transcriptomic studies and metabolic profiling revealed the co-regulation of starch metabolism-related genes and a clear metabolic separation between the periods. Most senescence-induced genes were found to be up-regulated more than twice in the starch-less mature leaves. Thus, dpe2/phs1 is a unique plant material source, with which we may study starch granule number regulation to obtain a more detailed understanding. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1286 KW - LCSM KW - RNA-Seq KW - metabolic-profiling KW - starch granule number regulation KW - starch initiation KW - starch degradation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-571250 SN - 1866-8372 IS - 1286 ER - TY - JOUR A1 - Muntaha, Sidratul Nur A1 - Li, Xiaoping A1 - Compart, Julia A1 - Apriyanto, Ardha A1 - Fettke, Jörg T1 - Carbon pathways during transitory starch degradation in Arabidopsis differentially affect the starch granule number and morphology in the dpe2/phs1 mutant background JF - Plant physiology and biochemistry : an official journal of the Federation of European Societies of Plant Physiology N2 - The Arabidopsis knockout mutant lacking both the cytosolic disproportionating enzyme 2 (DPE2) and the plastidial phosphorylase (PHS1) had a dwarf-growth phenotype, a reduced and uneven distribution of starch within the plant rosettes, and a lower starch granule number per chloroplast under standard growth conditions. In contrast, a triple mutant impaired in starch degradation by its additional lack of the glucan, water dikinase (GWD) showed improved plant growth, a starch-excess phenotype, and a homogeneous starch distribution. Furthermore, the number of starch granules per chloroplast was increased and was similar to the wild type. We concluded that ongoing starch degradation is mainly responsible for the observed phenotype of dpe2/phs1. Next, we generated two further triple mutants lacking either the phosphoglucan, water dikinase (PWD), or the disproportionating enzyme 1 (DPE1) in the background of the double mutant. Analysis of the starch metabolism revealed that even minor ongoing starch degradation observed in dpe2/phs1/pwd maintained the double mutant phenotype. In contrast, an additional blockage in the glucose pathway of starch breakdown, as in dpe2/phs1/ dpe1, resulted in a nearly starch-free phenotype and massive chloroplast degradation. The characterized mutants were discussed in the context of starch granule formation. KW - Starch granules KW - Starch metabolism KW - Starch granule number per KW - chloroplast KW - Starch morphology KW - LCSM KW - Arabidopsis thaliana Y1 - 2022 U6 - https://doi.org/10.1016/j.plaphy.2022.03.033 SN - 0981-9428 SN - 1873-2690 VL - 180 SP - 35 EP - 41 PB - Elsevier CY - Paris ER - TY - JOUR A1 - Li, Xiaoping A1 - Apriyanto, Ardha A1 - Flores Castellanos, Junio A1 - Compart, Julia A1 - Muntaha, Sidratul Nur A1 - Fettke, Jörg T1 - Dpe2/phs1 revealed unique starch metabolism with three distinct phases characterized by different starch granule numbers per chloroplast, allowing insights into the control mechanism of granule number regulation by gene co-regulation and metabolic profiling JF - Frontiers in Plant Science N2 - An Arabidopsis mutant lacking both the cytosolic Disproportionating enzyme 2 (DPE2) and the plastidial glucan Phosphorylase 1 (PHS1) revealed a unique starch metabolism. Dpe2/phs1 has been reported to have only one starch granule number per chloroplast when grown under diurnal rhythm. For this study, we analyzed dpe2/phs1 in details following the mutant development, and found that it showed three distinct periods of granule numbers per chloroplast, while there was no obvious change observed in Col-0. In young plants, the starch granule number was similar to that in Col-0 at first, and then decreased significantly, down to one or no granule per chloroplast, followed by an increase in the granule number. Thus, in dpe2/phs1, control over the starch granule number is impaired, but it is not defective in starch granule initiation. The data also indicate that the granule number is not fixed, and is regulated throughout plant growth. Furthermore, the chloroplasts revealed alterations during these three periods, with a partially strong aberrant morphology in the middle phase. Interestingly, the unique metabolism was perpetuated when starch degradation was further impaired through an additional lack of Isoamylase 3 (ISA3) or Starch excess 4 (SEX4). Transcriptomic studies and metabolic profiling revealed the co-regulation of starch metabolism-related genes and a clear metabolic separation between the periods. Most senescence-induced genes were found to be up-regulated more than twice in the starch-less mature leaves. Thus, dpe2/phs1 is a unique plant material source, with which we may study starch granule number regulation to obtain a more detailed understanding. KW - LCSM KW - RNA-Seq KW - metabolic-profiling KW - starch granule number regulation KW - starch initiation KW - starch degradation Y1 - 2022 U6 - https://doi.org/10.3389/fpls.2022.1039534 SN - 1664-462X SP - 1 EP - 16 PB - Frontiers CY - Lausanne, Schweiz ER -