RNAi Suppression of LEAFY Gives Stable Floral Sterility, and Reduced Growth Rate and Leaf Size, in Field-Grown Poplars.
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ABSTRACT:
SUBMITTER: Klocko AL
PROVIDER: S-EPMC8398303 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:affy_rnai_cadpoplar - affy_rnai_cadpoplars - This experiment aims to characterize global gene expression in young xylem of transgenic RNAi-CAD poplars in comparison to WT poplars. Cinnamyl Alcohol Dehydrogenase (CAD) is the final enzyme involved in the monolignol biosynthesis pathway. Transgenic poplars were produced using RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003) and exhibited the expected phenotype (red xylem, reduced CAD activity).Biological question (15 lines max):This experiment aims to characterize global gene expression in young xylem of transgenic RNAi-CAD poplars in comparison to WT poplars. Cinnamyl AlcoholDehydrogenase (CAD) is the final enzyme involved in the monolignol biosynthesispathway.Transgenic poplars were produced using RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003) and exhibited the expectedphenotype (red xylem, reduced CAD activity). -RNAi-CAD transgenic poplars were produced using hairpin RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003). For this transcriptome anaylsis, 2 independent transgenic lines (named pHG8-CAD2 and pHG8-CAD19) from the same transformation procedure were used as biological repeats. Four-month-old poplar plants were inclined at 30° in the greenhouse and sampled after 26 days. Young differentiating xylem originating from the lower side of stems - opposite wood - (ODX) was sampled on each individual tree by scrapping slightly the debarked stem with a scalpel. Samples were immediately flash frozen in liquid nitrogen, ground with mortar and pestle, and total RNAs were extracted from fine ground powder using the QIAGEN miRNeasy kit according to the manufacturer. One Affymetrix slide corresponds to a pool of RNA samples from 2-4 individual trees (WT, RNAi-CAD transgenic lines 2 and 19). Total number of slides = 2 genotypes (WT/RNAi line) x 1 tissue x 2 biological replicates = 4 slides were done.
2011-09-30 | GSE27063 | GEO
Project description:The transcription factor LEAFY is a master regulator of flowering and of flower development. It acts as a component of a switch that mediates the transition from the vegetative to the reproductive phase of plant development. Auxin is a plant hormone with many different roles in plant growth, including the induction of new primordia of both leaves and flowers at the shoot apex. We report that LEAFY acts in part by controlling the auxin response pathway in new primordia. Therefore, regulation of flower development by transcriptional master regulators and hormonal control of morphogenesis appear to be interacting processes. We found that hormone perception not only controls but is also controlled by the transcriptional signals that create plant form.
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Project description:Dual-use production systems that utilize the green leaves as well as seeds from amaranth are highly promising for small-scale farmers around the world. The leaves are an important source of nutrients for farming families, while seeds can provide income. Farmers who use amaranth as a dual-use crop are concerned about the impacts of defoliation on seed yield. This experiment tested defoliation at various intensities and frequencies (0, 25, 50, 75, and 100% defoliation, 1, 2, and 3 times) under controlled conditions as well as under Danish and Mexican field conditions. Defoliation tolerance was tested in a total of seven varieties, spanning the three primary grain amaranth species: A. cruentus, A. hypocondriacus, and A. caudatus. In all of the varieties and environments tested, we found that neither seed yield nor quality was impacted by a single defoliation event at intensities up to 50% leaf removal. We observed similar responses with two and three consecutive defoliations in which we removed 25% of all leaves. Greater frequency and intensity of defoliation resulted in reduced seed yield in some environments, while seed quality (protein content and 1000 KW) did not appear to be affected. Dual-use production systems should be promoted with small-scale farmers around the world as promising systems for improving local nutrition while maintaining profits from seed production. This paper provides baseline guidelines for farmers regarding optimal defoliation intensities and frequencies.
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Project description:affy_rnai_cadpoplar - affy_rnai_cadpoplars - This experiment aims to characterize global gene expression in young xylem of transgenic RNAi-CAD poplars in comparison to WT poplars. Cinnamyl Alcohol Dehydrogenase (CAD) is the final enzyme involved in the monolignol biosynthesis pathway. Transgenic poplars were produced using RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003) and exhibited the expected phenotype (red xylem, reduced CAD activity).Biological question (15 lines max):This experiment aims to characterize global gene expression in young xylem of transgenic RNAi-CAD poplars in comparison to WT poplars. Cinnamyl AlcoholDehydrogenase (CAD) is the final enzyme involved in the monolignol biosynthesispathway.Transgenic poplars were produced using RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003) and exhibited the expectedphenotype (red xylem, reduced CAD activity). -RNAi-CAD transgenic poplars were produced using hairpin RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003). For this transcriptome anaylsis, 2 independent transgenic lines (named pHG8-CAD2 and pHG8-CAD19) from the same transformation procedure were used as biological repeats. Four-month-old poplar plants were inclined at 30° in the greenhouse and sampled after 26 days. Young differentiating xylem originating from the lower side of stems - opposite wood - (ODX) was sampled on each individual tree by scrapping slightly the debarked stem with a scalpel. Samples were immediately flash frozen in liquid nitrogen, ground with mortar and pestle, and total RNAs were extracted from fine ground powder using the QIAGEN miRNeasy kit according to the manufacturer. One Affymetrix slide corresponds to a pool of RNA samples from 2-4 individual trees (WT, RNAi-CAD transgenic lines 2 and 19). Total number of slides = 2 genotypes (WT/RNAi line) x 1 tissue x 2 biological replicates = 4 slides were done. 4 arrays - poplar; normal vs rnai mutant comparaison
2011-09-29 | E-GEOD-27063 | biostudies-arrayexpress
Project description:Iodine deficiency disorders (IDD) in sub-Saharan African countries are related to low dietary I intake and generally combatted through salt iodisation. Agronomic biofortification of food crops may be an alternative approach. This study assessed the effectiveness of I biofortification of green vegetables (Brassica napus L and Amaranthus retroflexus L.) grown in tropical soils with contrasting chemistry and fertility. Application rates of 0, 5 and 10 kg ha-1 I applied to foliage or soil were assessed. Leaves were harvested fortnightly for ~ 2 months after I application before a second crop was grown to assess the availability of residual soil I. A separate experiment was used to investigate storage of I within the plants. Iodine concentration and uptake in sequential harvests showed a sharp drop within 28 days of I application in all soil types for all I application levels and methods. This rapid decline likely reflects I fixation in the soil. Iodine biofortification increased I uptake and concentration in the vegetables to a level useful for increasing dietary I intake and could be a feasible way to reduce IDD in tropical regions. However, biofortification of green vegetables which are subject to multiple harvests requires repeated I applications.
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Project description:The morphological variability of the flower in angiosperms, combined with its relatively simple structure, makes it an excellent model to study cell specification and the establishment of morphogenetic patterns. Flowers are the products of floral meristems, which are determinate structures that generate four different types of floral organs before terminating. The precise organization of the flower in whorls, each defined by the identity and number of organs it contains, is controlled by a multi-layered network involving numerous transcriptional regulators. In particular, the AGAMOUS (AG) MADS domain-containing transcription factor plays a major role in controlling floral determinacy in Arabidopsis thaliana in addition to specifying reproductive organ identity. This study aims to characterize the genetic interactions between the ULTRAPETALA1 (ULT1) and LEAFY (LFY) transcriptional regulators during flower morphogenesis, with a focus on AG regulation.Genetic and molecular approaches were used to address the question of redundancy and reciprocal interdependency for the establishment of flower meristem initiation, identity and termination. In particular, the effects of loss of both ULT1 and LFY function were determined by analysing flower developmental phenotypes of double-mutant plants. The dependency of each factor on the other for activating developmental genes was also investigated in gain-of-function experiments.The ULT1 and LFY pathways, while both activating AG expression in the centre of the flower meristem, functioned independently in floral meristem determinacy. Ectopic transcriptional activation by ULT1 of AG and AP3, another gene encoding a MADS domain-containing flower architect, did not depend on LFY function. Similarly, LFY did not require ULT1 function to ectopically determine floral fate.The results indicate that the ULT1 and LFY pathways act separately in regulating identity and determinacy at the floral meristem. In particular, they independently induce AG expression in the centre of the flower to terminate meristem activity. A model is proposed whereby these independent contributions bring about a switch at the AG locus from an inactive to an active transcriptional state at the correct time and place during flower development.
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