Fluorescent Arabidopsis – NIGHTSEA Stereo Microscope Fluorescence Adapter

Arabidopsis thaliana is a small flowering plant that is widely used as a model organism for a variety of studies. Below are two examples of uses involving fluorescence.

Arabidopsis plants – chemical response

Dr. John Celenza at Boston University is using GFP as a reporter in Arabidopsis to monitor plant defense responses. His plants have been engineered with GFP associated with the promoter for an enzyme (CYP79B2) that is produced when the plant responds to herbivory or pathogens. So when the plant is stressed and makes more of this enzyme it also makes GFP. This makes it easy to monitor the response non-obtrusively in real time.

Dr. Celenza uses the transgenic plants in combination with the NIGHTSEA Model SFA Stereo Microscope Fluorescence Adapter both in his research and in his laboratory courses. The images below were made using the longpass (left) and bandpass filter options. In this case the natural red chlorophyll fluorescence masks the GFP expression in the leaves

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Arabidopsis seeds – genetics

Dr. Scott Poethig and colleagues at the University of Pennsylvania have developed a novel transgenic strain of A. thaliana that has chromosomal segments with eGFP on one end and dsRed at the other. The segments can be followed in genetic crosses and manipulated via recombination. The transgenic strains will enable a variety of experiments, including phenotypic analyses of mutations with weak or environmentally sensitive phenotypes. They are intended for use in both research and education.

Dr. Poethig was looking for a cost-effective way to sort the genetically modified seeds in a teaching setting. He learned about the NIGHTSEA SFA and sent a set of seeds for us to test. There were five varieties – strong and weak green fluorescence, strong and weak red fluorescence, and non-fluorescent control. All of the variations were easy to see, even with the room lights on.

In each row below the image on the left was taken with white light illumination, the image in the center with the Royal Blue excitation/emission combination, and the image on the right with the Green excitation/emission combination. Equipment – NIGHTSEA Stereo Microscope Fluorescence Adapter, Motic SMZ168 trinocular stereo microscope, Canon EOS Rebel T2i camera.

(Click image for larger view)