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Augoustides, V.

Publications and source records attributed to Augoustides, V..

2 recordsLinked to original sources

ALPHA: A High Throughput System for Quantifying Growth In Aquatic Plants

The need for more sustainable agricultural systems is becoming increasingly apparent. The global demand for agricultural products -- food, feed, fuel and fiber -- will continue to increase as the global population continues to grow. This challenge is compounded by climate change. Not only does a changing climate make it difficult to maintain stable yields but current agricultural systems are a major source of greenhouse gas emissions and continue to drive the problem further. Therefore, future agricultural systems must not only increase production but also significantly decrease negative environmental impacts. One approach to addressing this is to begin breeding and cultivating new plant species that have fundamental sustainability advantages over our existing crops. The Lemnaceae, a.k.a duckweeds, are one such species that have potential to increase output and reduce the negative environmental impacts of agricultural production. Herein we describe the Automated Lab-scale PHenotyping Apparatus, ALPHA, for high-throughput phenotyping of Lemnaceae. ALPHA is being used for selective breeding of one species, Lemna gibba, toward the goal of creating a new crop for use in sustainable agricultural systems. ALPHA can be used on many small aquatic plant species to assess growth rates in different environmental conditions. A proof of principle use case is demonstrated where ALPHA is used to determine saltwater tolerance of 6 different varieties of L. gibba.

plant biology↗

Mapping the nuclear landscape with multiplexed super-resolution fluorescence microscopy

The nucleus coordinates many different processes. Visualizing how these are spatially organized requires imaging protein complexes, epigenetic marks, and DNA across scales from single molecules to the whole nucleus. To accomplish this, we developed a multiplexed imaging protocol to localize 13 different nuclear targets with nanometer precision in single cells. We show that nuclear specification into active and repressive states exists along a spectrum of length scales, emerging below one micron and becoming strengthened at the nanoscale with unique organizational principles in both heterochromatin and euchromatin. HP1- was positively correlated with DNA at the microscale but uncorrelated at the nanoscale. RNA Polymerase II, p300, and CDK9 were positively correlated at the microscale but became partitioned below 300 nm. Perturbing histone acetylation or transcription disrupted nanoscale organization but had less effect at the microscale. We envision that our imaging and analysis pipeline will be useful to reveal the organizational principles not only of the cell nucleus but also other cellular compartments.

cell biology↗