https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Regulation of fruit and seed response to heat and drought by sugars as nutrients and signals https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:20021 Wed 22 Mar 2023 17:00:54 AEDT ]]> Sugar conundrum in plant-pathogen interactions: Roles of invertase and sugar transporters depend on pathosystems https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:48013 Wed 15 Feb 2023 09:38:01 AEDT ]]> Regulation of tomato fruit set under heat stress by CWIN-mediated sucrose metabolism and signaling https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:22036 Wed 11 Apr 2018 17:01:12 AEST ]]> Cell wall invertase promotes fruit set under heat stress by suppressing ROS-independent cell death https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:26958 Solanum lycopersicum) with its CWIN inhibitor gene silenced and focusing on ovaries and fruits at 2 d before and after pollination, respectively. We found that the increase of CWIN activity suppressed LMHS-induced programmed cell death in fruits. Surprisingly, measurement of the contents of H₂O₂ and malondialdehyde and the activities of a cohort of antioxidant enzymes revealed that the CWIN-mediated inhibition on programmed cell death is exerted in a reactive oxygen species-independent manner. Elevation of CWIN activity sustained Suc import into fruits and increased activities of hexokinase and fructokinase in the ovaries in response to LMHS. Compared to the wild type, the CWIN-elevated transgenic plants exhibited higher transcript levels of heat shock protein genes Hsp90 and Hsp100 in ovaries and HspII17.6 in fruits under LMHS, which corresponded to a lower transcript level of a negative auxin responsive factor IAA9 but a higher expression of the auxin biosynthesis gene ToFZY6 in fruits at 2 d after pollination. Collectively, the data indicate that CWIN enhances fruit set under LMHS through suppression of programmed cell death in a reactive oxygen species-independent manner that could involve enhanced Suc import and catabolism, HSP expression, and auxin response and biosynthesis.]]> Sat 24 Mar 2018 07:27:01 AEDT ]]> Genotypic differences in pod wall and seed growth relate to invertase activities and assimilate transport pathways in asparagus bean https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:22243 Vigna unguiculata ssp. sesquipedialis) differing in pod wall and seed growth rates. Pod growth dominates over seed growth in genotype ‘Zhijiang 121’ but not in ‘Zhijiang 282’ in which a ‘bulging pod’ phenotype is apparent from 8 d post-anthesis (dpa) onward. Methods: Seed and pod wall growth rates and degree of pod-bulging were measured in the two genotypes together with assays of activities of sucrose-degrading enzymes and sugar content in pod wall and seed and evaluation of cellular pathways of phloem unloading in seed coat using a symplasmic fluorescent dye, 5(6)-carboxyfluorescein (CF). Key Results: Activities of cell wall, cytoplasmic and vacuolar invertases (CWIN, CIN and VIN) were significantly smaller in pod walls of ‘282’ than in ‘121’ at 10 dpa onwards. Low INV activities were associated with weak pod wall growth of ‘282’. In seed coats, CF was confined within the vasculature in ‘282’ but moved beyond the vasculature in ‘121’, indicating apoplasmic and symplasmic phloem unloading, respectively. Higher CWIN activity in ‘282’ seed coats at 6–8 dpa correlated with high hexose concentration in embryos and enhanced early seed growth. However, CWIN activity in ‘282’ decreased significantly compared with ‘121’ from 10 dpa onwards, coinciding with earlier commencement of nuclei endoreduplication in their embryos. Conclusions: The study shows genotypic differences between ‘bulging pod’ and ‘non-bulging’ phenotypes of asparagus bean in sucrose metabolism in relation to the pathway of phloem unloading in developing seed coats, and to pod and seed growth. Low INV activity in pod wall corresponds to its shortened and weak growth period; by contrast, the apoplasmic path in the seed coat is associated with high CWIN activity and strong early seed growth.]]> Sat 24 Mar 2018 07:17:31 AEDT ]]> A simple, rapid, and reliable protocol to localize hydrogen peroxide in large plant organs by DAB-mediated tissue printing https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:18693 Mon 20 Jul 2015 17:41:44 AEST ]]>