bioRxiv ScienceSearch

Biology subjects

Kramer, D. M.

Publications and source records attributed to Kramer, D. M..

2 recordsLinked to original sources

OLIVER: A Tool for Visual Data Analysis on Longitudinal Plant Phenomics Data

There is a critical unmet need for new tools to analyze and understand \"big data\" in the biological sciences where breakthroughs come from connecting massive genomics data with complex phenomics data. By integrating instant data visualization and statistical hypothesis testing, we have developed a new tool called OLIVER for phenomics visual data analysis with a unique function that any user adjustment will trigger real-time display updates for any affected elements in the workspace. By visualizing and analyzing omics data with OLIVER, biomedical researchers can quickly generate hypotheses and then test their thoughts within the same tool, leading to efficient knowledge discovery from complex, multi-dimensional biological data. The practice of OLIVER on multiple plant phenotyping experiments has shown that OLIVER can facilitate scientific discoveries. In the use case of OLIVER for large-scale plant phenotyping, a quick visualization identified emergent phenotypes that are highly transient and heterogeneous. The unique circular heat map with false-color plant images also indicates that such emergent phenotypes appear in different leaves under different conditions, suggesting that such previously unseen processes are critical for plant responses to dynamic environments.

bioinformatics

Loss of Peroxisomal Hydroxypyruvate Reductase Inhibits Triose Phosphate Isomerase but Stimulates Cyclic Photosynthetic Electron Flow and the Glc-6P-Phosphate Shunt

The oxygenation of ribulose 1,5-bisphosphate by Rubisco is the first step in photorespiration and reduces the efficiency of photosynthesis in C3 plants. Our recent data indicates that mutants in photorespiration have increased rates of photosynthetic cyclic electron flow around photosystem I. We investigated mutant lines lacking peroxisomal hydroxypyruvate reductase to determine if there are connections between 2-PG accumulation and cyclic electron flow. We found that 2-PG is a competitive inhibitor of triose phosphate isomerase (TPI), an enzyme in the Calvin-Benson cycle that converts glyceraldehyde 3-phosphate to dihydroxyacetone phosphate. This block in metabolism could be overcome if glyceraldehyde 3-phosphate is exported to the cytosol where the cytosolic triose phosphate isomerase could convert it to dihydroxyacetone phosphate. We found evidence that carbon is reimported as Glc-6P-phosphate forming a cytosolic bypass around the block of stromal TPI. However, this also stimulates a Glc-6P-phosphate shunt, which consumes ATP, which can be compensated by higher rates of cyclic electron flow.\n\nOnce Sentence SummaryTriose phosphate isomerase is inhibited in plants lacking hydroxypyruvate reductase 1 and this is overcome by exporting triose phosphate to the cytosol and importing Glc-6P, which stimulates a Glc-6P-phosphate shunt and cyclic electron flow.

plant biology