Dataset Information

Structural and Metabolic Transitions of C4 Leaf Development and Differentiation Defined by Microscopy and Quantitative Proteomics in Maize

ABSTRACT: C4 grasses, such as maize (Zea mays), have high photosynthetic efficiency through combined biochemical and structural adaptations.C4 photosynthesis is established along the developmental axis of the leafblade, leading from an undifferentiated leaf base just above the ligule into highly specialized mesophyll cells (MCs) and bundle sheath cells (BSCs) at the tip. To resolve the kinetics of maize leaf development and C4 differentiation and to obtain a systems-level understanding of maize leaf formation, the accumulation profiles of proteomes of the leaf and the isolated BSCs with their vascular bundle along the developmental gradient were determined using large-scale mass spectrometry. This was complemented by extensive qualitative and quantitative microscopy analysis of structural features (e.g., Kranz anatomy, plasmodesmata, cell wall, and organelles). More than 4300 proteins were identified and functionally annotated. Developmental protein accumulation profiles and hierarchical cluster analysis then determined the kinetics of organelle biogenesis, formation of cellular structures, metabolism, and coexpression patterns. Two main expression clusters were observed, each divided in subclusters, suggesting that a limited number of developmental regulatory networks organize concerted protein accumulation along the leaf gradient. The coexpression with BSC and MC markers provided strong candidates for further analysis of C4 specialization, in particular transporters and biogenesis factors. Based on the integrated information, we describe five developmental transitions that provide a conceptual and practical template for further analysis. An online protein expression viewer is provided through the PlantProteomeDatabase.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Zea Mays (maize)

TISSUE(S): Leaf

SUBMITTER: Tami Leppert

LAB HEAD: Klaas van Wijk

PROVIDER: PXD046098 | Pride | 2023-10-12

REPOSITORIES: Pride

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Publications

Structural and metabolic transitions of C4 leaf development and differentiation defined by microscopy and quantitative proteomics in maize.

Majeran Wojciech W Friso Giulia G Ponnala Lalit L Connolly Brian B Huang Mingshu M Reidel Edwin E Zhang Cankui C Asakura Yukari Y Bhuiyan Nazmul H NH Sun Qi Q Turgeon Robert R van Wijk Klaas J KJ

The Plant cell 20101116 11

C(4) grasses, such as maize (Zea mays), have high photosynthetic efficiency through combined biochemical and structural adaptations. C(4) photosynthesis is established along the developmental axis of the leaf blade, leading from an undifferentiated leaf base just above the ligule into highly specialized mesophyll cells (MCs) and bundle sheath cells (BSCs) at the tip. To resolve the kinetics of maize leaf development and C(4) differentiation and to obtain a systems-level understanding of maize le ...[more]

PMID: 21081695

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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.

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Dataset Information

Structural and Metabolic Transitions of C4 Leaf Development and Differentiation Defined by Microscopy and Quantitative Proteomics in Maize

Publications

Structural and metabolic transitions of C4 leaf development and differentiation defined by microscopy and quantitative proteomics in maize.

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