Authors

Kathleen Duncan Foothill College	Leonore Reiser The Arabidopsis Information Resource

Brief Overview

Develop two new laboratory modules and integrate three existing modules to introduce students to the the field of phylogenetic systematics and the tools available in the field of bioinformatics. These labs would be used after studying the basic principles of evolutionary theory.

Secondary goals include:

1. Give a thorough introduction to the concept of model organisms in general and Arabidopsis in particular.
2. Make connections between topics covered in all four courses (Biol 1A - 1D).

   Laboratory modules:

   Module 1 = Chemicules - fictitious organisms used to give students experience in building cladograms
   Module 2 = Patterns of HIV evolution
   Module 3 = Explore the phylogeny of the cryptochrome gene family in Arabidopsis
   Module 4 = Explore the phylogeny of the PAS domain (part of the blue light receptor) across diverse taxa including bacteria, fungi, animals, and other eukaryotes.
   Module 5 = One organisms, three genomes

General format of lab:

• Students will be working in groups of 4 with six to eight groups/lab
• During the first hour three of the groups will report on work from the previous lab. Each group alotted 5-10 min for presentation and 10 minutes of brainstorming with the class.
• Instructor introduces next problem (15-30min)
• Students work collaborativly in groups for 1.5 hours.
• Students complete their work before the next lab period.

Background information on the cryptochrome gene family:

Plants have an extensive and complex network of responses to their environment (can't run, can't hide, can't pick up and move to a better neighborhood). Adaptation to light environment requires the ability to receive a light signal and translate that to a cellular and ultimately a developmental response. Plants have different responses to different wavelengths and intensities of light.

By analyzing mutations in Arabidopsis that affect the response of plants to blue light genetic elements of the response network were identified including blue light photoreceptors. Members of the cryptochrome gene family have diverse roles such as DNA repair, blue light phototransduction and circadian rhythm. (Note: in the plant blue light receptors there is no photolyase activity.)

Students will be asked to first explore the gene duplication and divergence events that have occurred in Arabidopsis. In the following lab, students will be asked to explore the phylogeny of this gene family in diverse taxa and speculate on the role of blue light receptors in bacteria, flowering plants, and animals (eg: what is a blue light receptor doing in the pineal gland?)

Resources and References

www.arabidopsis.org/info/aboutarabidopsis.html

www.arabidopsis.org

www.bioquest.org

biology.ncsa.uiuc.edu