title: Involvement of ethylene and polyamines biosynthesis and abdominal phloem tissues characters of wheat caryopsis during grain filling under stress conditions.
abstract: Severe water deficit (SD) severely limited the photo-assimilate supply during the grain-filling stages. Although the ethylene and polyamines (PAs) have been identified as important signaling molecules involved in stress tolerance, it is yet unclear how 1-Aminocylopropane-1-carboxylic acid (ACC) and PA biosynthesis involving wheat abdominal phloem characters mitigate SD-induced filling inhibition. The results obtained indicated that the SD down-regulated the TaSUT1 expression and decreased the activities of sucrose synthase (SuSase, EC2.4.1.13), ADP glucose pyrophosphorylase (AGPase, EC2.7.7.27), soluble starch synthase (SSSase, EC2.4.1.21), then substantially limited grain filling. As a result, increased ACC and putrescine (Put) concentrations and their biosynthesis-related gene expression reduced spermidine (Spd) biosynthesis under SD condition. And, the ACC and PA biosynthesis in inferior grains was more sensitive to SD than that in superior grains. Intermediary cells (ICs) of caryopsis emerged prematurely under SD to compensate for the weakened photo-assimilate transport functions of sieve elements (SEs). Finally, plasmolysis and nuclear chromatin condensation of phloem parenchyma cells (PPC) and membrane degradation of SEs, as well as the decreased ATPase activity on plasma membranes of ICs and PPC at the later filling stage under SD were responsible for the considerably decreased weight of inferior grains.
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.|Beijing Academy of Agricultural and Forestry Sciences, Beijing Engineering Research Center for Hybrid Wheat. Beijing, 100097, China.
authors.forename: Weibing
authors.initials: W
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Beijing Academy of Agricultural and Forestry Sciences, Beijing Engineering Research Center for Hybrid Wheat. Beijing, 100097, China.
authors.forename: Zhilie
authors.initials: Z
authors.lastname: Qin
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Mengjing
authors.initials: M
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Yongli
authors.initials: Y
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Dangwei
authors.initials: D
authors.lastname: Pang
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Crop Biology, Ministry of Science and Technology, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors.forename: Zhenlin
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000598:Amino Acids, Cyclic / Q000378:metabolism; D002241:Carbohydrates / Q000032:analysis; D005030:Ethylenes / Q000096:biosynthesis*; D018506:Gene Expression Regulation, Plant; D052585:Phloem / Q000378:metabolism* / Q000648:ultrastructure; D010788:Photosynthesis; D010940:Plant Proteins / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism*; D012995:Solubility; D013213:Starch / Q000378:metabolism; D013312:Stress, Physiological; D013395:Sucrose / Q000378:metabolism; D014908:Triticum / Q000033:anatomy & histology* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D014867:Water
chemical_list: D000598:Amino Acids, Cyclic; D002241:Carbohydrates; D005030:Ethylenes; D010940:Plant Proteins; D011073:Polyamines; D014867:Water; C023863:1-aminocyclopropane-1-carboxylic acid; D013395:Sucrose; D013213:Starch; C036216:ethylene; D000251:Adenosine Triphosphatases