Regulation of root greening by light and auxin and cytokinin signalling in Arabidopsis
Ontology highlight
ABSTRACT: For microarray analysis plants (Arabidopsis thaliana) were grown for 7 days in the presence or absence of 1 uM 6-benzyladenine following growth on MS medium for 7 days.
Project description:Arabidopsis rosette leaves were harvested from plants grown under <br><br>different photoperiods under 100 M-5mol photons m-2 s-1 at 20 M-0C. <br><br><br><br>In the first experiment plants grown under short day conditions 8L/16D (8 h light / 16 h dark) for 4 weeks were compared with plants <br><br>grown under long day (16L/8D) for 3 weeks.<br><br><br><br>In the second experiment plants grown under 12L/12D <br><br>for 2 weeks were compared with plants grown first 2 weeks under <br><br>12L/12D and then two days under short day (8L/16D) conditions.
Project description:Arabidopsis thaliana wildtype (Col-0) was compared with the ntrc mutant under different photoperiods (short day: 8h/16h; long day 16h/8h light/dark) and different ages (10d and 28/21d).
Project description:Transcription factors play a fundamental role in plants by orchestrating temporal and spatial gene expression in response to environmental stimuli. Several R2R3-MYB genes of the Arabidopsis subgroup 4 (Sg4) share a C-terminal EAR motif signature recently linked to stress response in angiosperm plants. It is reported here that nearly all Sg4 MYB genes in the conifer trees Picea glauca (white spruce) and Pinus taeda (loblolly pine) form a monophyletic clade (Sg4C) that expanded following the split of gymnosperm and angiosperm lineages. Deeper sequencing in P. glauca identified 10 distinct Sg4C sequences, indicating over-represention of Sg4 sequences compared with angiosperms such as Arabidopsis, Oryza, Vitis, and Populus. The Sg4C MYBs share the EAR motif core. Many of them had stress-responsive transcript profiles after wounding, jasmonic acid (JA) treatment, or exposure to cold in P. glauca and P. taeda, with MYB14 transcripts accumulating most strongly and rapidly. Functional characterization was initiated by expressing the P. taeda MYB14 (PtMYB14) gene in transgenic P. glauca plantlets with a tissue-preferential promoter (cinnamyl alcohol dehydrogenase) and a ubiquitous gene promoter (ubiquitin). Histological, metabolite, and transcript (microarray and targeted quantitiative real-time PCR) analyses of PtMYB14 transgenics, coupled with mechanical wounding and JA application experiments on wild-type plantlets, allowed identification of PtMYB14 as a putative regulator of an isoprenoid-oriented response that leads to the accumulation of sesquiterpene in conifers. Data further suggested that PtMYB14 may contribute to a broad defence response implicating flavonoids. This study also addresses the potential involvement of closely related Sg4C sequences in stress responses and plant evolution.
Project description:The involvement of two R2R3-MYB genes from Pinus taeda L., PtMYB1 and PtMYB8, in phenylpropanoid metabolism and secondary cell wall biogenesis was investigated in planta. These pine MYBs were constitutively overexpressed (OE) in Picea glauca (Moench) Voss, used as a heterologous conifer expression system. Morphological, histological, chemical (lignin and soluble phenols), and transcriptional analyses, i.e. microarray and reverse transcription quantitative PCR (RT-qPCR) were used for extensive phenotyping of MYB-overexpressing spruce plantlets. Upon germination of somatic embryos, root growth was reduced in both transgenics. Enhanced lignin deposition was also a common feature but ectopic secondary cell wall deposition was more strongly associated with PtMYB8-OE. Microarray and RT-qPCR data showed that overexpression of each MYB led to an overlapping up-regulation of many genes encoding phenylpropanoid enzymes involved in lignin monomer synthesis, while misregulation of several cell wall-related genes and other MYB transcription factors was specifically associated with PtMYB8-OE. Together, the results suggest that MYB1 and MYB8 may be part of a conserved transcriptional network involved in secondary cell wall deposition in conifers.
Project description:Comparison of transcript profiles of E. coli LZ41 and LZ54 fishns mutant strains containing drug-resistant alleles of different topoisomerase genes to distinguish gene transcripts associated either with relaxation or hypernegative supercoiling in absence of transcriptional regulator FIS and H-NS.
Project description:Comparison of transcript profiles of E. coli LZ41fishns and LZ54fishns strains containing drug-resistant alleles of different topoisomerase genes to distinguish gene transcripts associated either with relaxation or hypernegative supercoiling.
Project description:The potential of the earthworm Eisenia andrei to reduce soil methanogens, and thus methane emissions to the atmosphere, were assayed in a microcosm experiment. Soils were incubated for 2, 4 and 6 months. We measured microarray parameters (methanogenic diversity) at the start of incubation, as well as after 2, 4 and 6 months of incubation in microcosms with or without earthworms. Methanosarcina barkeri was the most abundant genus that was revealed by AnaeroChip in our experiment.
Project description:Subolesin is an evolutionary conserved protein that was recently discovered in Ixodes scapularis as a tick protective antigen and has a role in tick blood digestion, reproduction and development. In other organisms, subolesin orthologs may be involved in the control of developmental processes. Because of the profound effect of subolesin knockdown in ticks and other organisms, we hypothesized that subolesin has a role in gene expression, thus affecting multiple cellular processes. The objective of this study was to provide support for the role of subolesin in gene expression. Keywords: time course Total RNA was prepared and pooled from subolesin dsRNA- and saline-injected ticks at 6 and 9 dpi (5 and 8 days of feeding).
Project description:Brucella ovis causes an important disease characterized by decreased fertility in rams, sporadic abortions in ewes and increased lamb mortality. The live attenuated B. melitensis Rev.1 vaccine is considered the best vaccine available against this infection. However, this vaccine shows variable protective efficacy ranging from 40% to 100%.The objective of this study was to identify possible correlates of protective response to B. ovis infection through the characterization by microarray hybridization and real-time RT-PCR of inflammatory and immune response genes upregulated in rams previously immunized with the B. melitensis Rev 1 vaccine strain and experimentally challenged with B. ovis. Gene expression profiles were compared before and after challenge with B. ovis between rams protected and those vaccinated but found infected after challenge. The genes upregulated in vaccinated and protected rams provide possible correlates of protective response to B. ovis infection in rams immunized with the B. melitensis Rev 1 vaccine. Gene expression profiles were compared before and after vaccination and challenge with B. ovis between rams protected with the B. melitensis Rev 1 vaccine strain and those vaccinated but infected after challenge. Total RNA was isolated from buffy coat samples before vaccination (T0), after vaccination and before challenge (T1) and 60 days post challenge (T2) using TriReagent (Sigma, St. Louis, MO, USA)