The Experts below are selected from a list of 6 Experts worldwide ranked by ideXlab platform
Peter M. Ray - One of the best experts on this subject based on the ideXlab platform.
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Regulation of f3-Glucan Synthetase Activity by Auxin in Pea Stem Tissue
2016Co-Authors: Peter M. RayAbstract:Treatment of pea stem segments with indoleacetic acid (IAA) causes within 1 hour a 2- to 4-fold increase in activity of particulate Uridine diphosphoglucose-dependent p-glucan synthetase obtainable from the tissue. The IAA effect is observable in tissue from all parts of the elongation zone of the pea stem, and also in older tissue that is not capable of a cell enlargement response to IAA. A large increase in activity is caused by IAA only if synthetase activity in the isolated tissue has first been allowed to fail substantially below the intact plant level, and only if sucrose is supplied along with IAA. Treatment of tissue with sucrose alone after a period of sugar starvation causes a transient rise of synthetase activity. The decline in synthetase activity in absence of IAA, the rise caused by IAA, and the transient rise caused by sucrose are all strongly temperature-dependent. IAA and sucrose do not affect the activity of isolated synthetase particles. Synthetase activity in vivo is sensitive to as low as 0.1 M IAA and is increased by IAA analogues that are active as auxins on elongation but not by nonauxin analogues. Activity begins to rise 10 to 15 minutes after exposure to IAA, which places this among the most rapid enzyme effects of a plant growth regulator heretofore demonstrated, and among the most rapid known metabolic effects of auxins. The effect is seen also with polysaccharide synthetase activity using Uridine Diphosphate-galactose or Uridine Diphosphate-Xylose as substrates, and to a lesser extent with guanosine diphosphoglucose-dependent glucan synthetase activity. Glucan synthetase from IAA-treated tissue appears to have a higher affinity for Uridine Diphosphate-glucose than the control.
Z.y. Sun - One of the best experts on this subject based on the ideXlab platform.
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Transcriptome profiling in Salix matsudana during refilling xylem vessels after embolism
Biologia plantarum, 2019Co-Authors: J.x. Liu, Z.y. SunAbstract:The objective of this study is to understand the role of bark water uptake in refilling of xylem vessels after embolism in Salix matsudana. Further, we determined expression of genes closely related to xylem embolism repair. The isolated branch segments of S. matsudana were soaked in deionized water and after 2 h, the micro-computed tomography (CT) images, volume of xylem sap, osmotic potential of xylem sap, and the content of starch and soluble sugar were measured. At the same time, Illumina high-throughput sequencing (Hi Seq TM) was applied to obtain the xylem transcriptome profiling. The results showed that the soaked branches had 58.86 % fewer embolized vessels than branches before soaking. The volume of xylem sap was increased by 21.51 % in comparison with initial sample and the osmotic potential (Ψs) of xylem sap was decreased by 87.18 %. The content of ions and soluble sugars in the xylem sap significantly increased after soaking. Fourteen genes were clarified and found to have a significant correlation with osmotic potential of xylem sap. Our findings showed that water can enter the xylem vessels through the bark and can repair the xylem embolism in branches. The saccharides played an important role in osmotic potential difference formation and the genes UXL1 (Uridine Diphosphate-Xylose synthase 1), UGDH (Uridine Diphosphate-glucose 6-dehydrogenase), BGLU40 (β-glucosidase 40), PPE8B (pectinesterase/pectinesterase inhibitor), UG1 (Uridine Diphosphate-glucuronate 1), and XYL4 (β-D-xylosidase 4)) were the key genes to promote embolized vessels refilling.
J.x. Liu - One of the best experts on this subject based on the ideXlab platform.
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Transcriptome profiling in Salix matsudana during refilling xylem vessels after embolism
Biologia plantarum, 2019Co-Authors: J.x. Liu, Z.y. SunAbstract:The objective of this study is to understand the role of bark water uptake in refilling of xylem vessels after embolism in Salix matsudana. Further, we determined expression of genes closely related to xylem embolism repair. The isolated branch segments of S. matsudana were soaked in deionized water and after 2 h, the micro-computed tomography (CT) images, volume of xylem sap, osmotic potential of xylem sap, and the content of starch and soluble sugar were measured. At the same time, Illumina high-throughput sequencing (Hi Seq TM) was applied to obtain the xylem transcriptome profiling. The results showed that the soaked branches had 58.86 % fewer embolized vessels than branches before soaking. The volume of xylem sap was increased by 21.51 % in comparison with initial sample and the osmotic potential (Ψs) of xylem sap was decreased by 87.18 %. The content of ions and soluble sugars in the xylem sap significantly increased after soaking. Fourteen genes were clarified and found to have a significant correlation with osmotic potential of xylem sap. Our findings showed that water can enter the xylem vessels through the bark and can repair the xylem embolism in branches. The saccharides played an important role in osmotic potential difference formation and the genes UXL1 (Uridine Diphosphate-Xylose synthase 1), UGDH (Uridine Diphosphate-glucose 6-dehydrogenase), BGLU40 (β-glucosidase 40), PPE8B (pectinesterase/pectinesterase inhibitor), UG1 (Uridine Diphosphate-glucuronate 1), and XYL4 (β-D-xylosidase 4)) were the key genes to promote embolized vessels refilling.
