Project description:To investigate the developmental gradient of the third maize leaf, the light exposed area of the leaf (corresponding to 18cm of leaf) and 2cm shaded by the sheath were sampled in ten slices. Four replicates were collected, immediately shock frozen in liquid nitrogen and subsequently cut into 2cm slices. At least 10 plants were pooled for each biological replicate. We have systematically analyzed a developmental gradient of the third maize leaf from the point of emergence into the light to the tip in ten continuous leaf slices to study organ development and physiological and biochemical functions. Transcriptome analysis, oxygen sensitivity of photosynthesis, delta-13C values, and photosynthetic rate measurements showed that the maize leaf undergoes a sink to source transition without an intermediate phase of C3 photosynthesis or operation of a photorespiratory carbon pump. Metabolome and transcriptome analysis, chlorophyll and protein measurements, as well as dry weight determination showed continuous gradients for all analyzed items. The absence of binary on-off switches and regulons pointed to a morphogradient along the leaf as the determining factor of developmental stage. Analysis of transcription factors for differential expression along the leaf gradient defined a list of putative regulators orchestrating the sink-to-source transition and establishment of C4 photosynthesis. Finally, transcriptome and metabolome analysis, as well as enzyme activity measurements, and absolute quantification of selected metabolites revised the current model of maize C4 photosynthesis. All datasets are included within the publication to serve as a resource for maize leaf systems biology. For the transcriptional analysis, the goal of the study was to (i) identify whether the leaf contains binary switches for genes involved in photosynthesis, (ii)characterize the patterns of gene expression in the leaf, (iii) provide independent validation of maize leaf expression experiments published in Li et al. (2011) and (iv) determine transcripts co-expressed with key transcripts of C4 photosynthesis. To this end, changed transcripts were determined by ANOVA and characterized by K-means and hierachical clustering.
Project description:We have generated over 80 million 32 nt reads generated from RNA samples isolated from the tip and base of a developing Mo17 leaf. A comparision of these data with the maize AGP resulted in the confirmation of approximately 88% of the maize filtered gene set Keywords: Transcriptome analysis
Project description:Maize husk leaf - the outer leafy layers covering the ear - modulates kernel yield and quality. Despite its importance, however, the genetic controls underlying husk leaf development remain elusive. Our previous genome-wide association study identified a single nucleotide polymorphism located in the gene RHW1 (Regulator of Husk leaf Width) that is significantly associated with husk leaf-width diversity in maize. Here, we further demonstrate that a polymorphic 18-bp InDel (insertion/deletion) variant in the 3' untranslated region of RHW1 alters its protein abundance and accounts for husk leaf width variation. RHW1 encodes a putative MYB-like transcriptional repressor. Disruption of RHW1 altered cell proliferation and resulted in a narrower husk leaf, whereas RHW1 overexpression yielded a wider husk leaf. RHW1 positively regulated the expression of ZCN4, a well-known TFL1-like protein involved in maize ear development. Dysfunction of ZCN4 reduced husk leaf width even in the context of RHW1 overexpression. The InDel variant in RHW1 is subject to selection and is associated with maize husk leaf adaption from tropical to temperate regions. Overall, our results identify that RHW1-ZCN4 regulates a pathway conferring husk leaf width variation at a very early stage of husk leaf development in maize.
Project description:To investigate the developmental gradient of the third maize leaf, the light exposed area of the leaf (corresponding to 18cm of leaf) and 2cm shaded by the sheath were sampled in ten slices. Four replicates were collected, immediately shock frozen in liquid nitrogen and subsequently cut into 2cm slices. At least 10 plants were pooled for each biological replicate. We have systematically analyzed a developmental gradient of the third maize leaf from the point of emergence into the light to the tip in ten continuous leaf slices to study organ development and physiological and biochemical functions. Transcriptome analysis, oxygen sensitivity of photosynthesis, delta-13C values, and photosynthetic rate measurements showed that the maize leaf undergoes a sink to source transition without an intermediate phase of C3 photosynthesis or operation of a photorespiratory carbon pump. Metabolome and transcriptome analysis, chlorophyll and protein measurements, as well as dry weight determination showed continuous gradients for all analyzed items. The absence of binary on-off switches and regulons pointed to a morphogradient along the leaf as the determining factor of developmental stage. Analysis of transcription factors for differential expression along the leaf gradient defined a list of putative regulators orchestrating the sink-to-source transition and establishment of C4 photosynthesis. Finally, transcriptome and metabolome analysis, as well as enzyme activity measurements, and absolute quantification of selected metabolites revised the current model of maize C4 photosynthesis. All datasets are included within the publication to serve as a resource for maize leaf systems biology. For the transcriptional analysis, the goal of the study was to (i) identify whether the leaf contains binary switches for genes involved in photosynthesis, (ii)characterize the patterns of gene expression in the leaf, (iii) provide independent validation of maize leaf expression experiments published in Li et al. (2011) and (iv) determine transcripts co-expressed with key transcripts of C4 photosynthesis. To this end, changed transcripts were determined by ANOVA and characterized by K-means and hierachical clustering. Four replicates were collected for each of the ten consecutive leaf slices resulting in 40 one color arrays. Slice 1 represents the tip of the leaf, slice 10 the lowermost slice which is shaded by the sheath with all slices in between consecutively numbered.
Project description:The exxpression profilling of chilling responsive and growth regulated microRNAs of maize hybrid ADA313 was conducted. Maize seedling were subjected to chilling temperature then meristem, elongation and mature growth zones were sampled. 321 known maize microRNA expression level were determined and compared between meristem, elongation and mature zones. Determining and validating of chilling responsive microRNAs associated with leaf growth of hybrid maize (Zea mays L.) ADA313
Project description:Two-organism transcriptome profiling of infected seedling, adult leaf, and tassel demonstrated that both the host and pathogen exhibit organ-specific expression programs. Phenotypic screening of U. maydis mutants deleted for suites of secreted protein genes and maize growth mutants demonstrated organ-restricted tumorigenesis. Two-dye, competitive hybridizations were performed on Agilent oligo arrays. Keywords: maize, pathogen, fungus, Ustilago, organ-specificity
Project description:We have generated over 80 million 32 nt reads generated from RNA samples isolated from the tip and base of a developing Mo17 leaf. A comparision of these data with the maize AGP resulted in the confirmation of approximately 88% of the maize filtered gene set Keywords: Transcriptome analysis Examination of two different RNA samples from two different segments of a developing 3rd leaf
Project description:Transcriptome of three zones (from the base to 3.5 cm, from 3.5 to 7.0 cm and from 7.0 to 10.5 cm) of the developing fourth leaf of maize B104 plants was profiled at two days after leaf appearance (DALA). Only leaf samples were taken for well-watered plants.
Project description:This was a comparative transcriptome analysis by using high throughput sequencing. To assess the effects of heat stress on maize alternative splicing we used a controlled environment facility called the Enviratron to simulate field conditions. For our experiments, maize plants were subjected to conditions simulating normal diurnal rhythms of light and temperature, with increasing maximal daily temperature (MDT). Maize plants were grown continuously under four different temperature regimes with simulated morning temperatures ramped up over 6 hr to the MDT of 31°C, 33°C, 35°C or 37°C and simulated evening/night time temperatures ramped down over 8 hr to 10°C below the MDT. We tracked the alternative splicing events of maize W22 seedlings grow under different temperatures (MDT of 31°C, 33°C, 35°C or 37°C) to evaluate how different MDTs affect the program of gene alternative splicing in maize. RNA was extracted from small strips of leaf lamina excised from the first fully expanded leaf of V4 and V5 W22 plants (at 20 and 27 DAG, respectively). Plants were sampled in triplicates.