Transcript The (Indirect) Costs of Conducting Research: A study of

Comparison of DNA Sequence of H3 (Histone) and Centromere H3
(Cen H3) in Memebers of the Gossypium (Cotton) Genus
Gene McClugage, Ryan Rapp, Jonathan Wendel and EEOB at Iowa State University
ABSTRACT
DISCUSSION
The goal of this research was to analyze the Histone3(H3)
gene sequence of the members of the Gossypium genus and
the Centromere H3 (CenH3). In comparing these two sets of
genes sequences we wanted to determine the evolutionary
rate of change as each species diverged from the parent
species for the CenH3. This also will verify or improve upon
the phylogenetic relationships currently accepted. This
research then sets the groundwork for understanding the
mechanisms that led to the diversification of CenH3 in the
various Gossypium species.
Arabidopsis has both the H3 Histone and Centromeric H3
protein complex . It was found that the centromeric H3
proteins of Arabidopsis. thaliana and A. arenosa showed
remarkable adaptive evolution. Suggesting the same
mechanisms for selection pressure in the species.
In Gossypium species it would then be assumed that the
same pattern should be exhibited when the similar
centromeric H3 complex and Histone H3 complex is
analyzed. This logic would also be supported by the
recent and rapid diversification of the Gossypium genus.
At this point in the research there is no definitive answer
as to whether or not Cen H3 shows significant diversity
among the various species of Gossypium.
BACKGROUND
The centromeres (CenH3) protein of the different Gossypium
species as well as many other species has shown quick
evolutionary change. In comparison the Histone H3 shows
very little change over time between the different species.
The H3 binds approximately 120 bp as does the CenH3. The
centromere H3 is a key protein of the centromere that
participates in the binding of the chromosome to the spindle
fibers during mitosis or meiosis.
RESEARCH QUESTION
How different or similar are the Cen H3 sequences
between the various species of Gossypium genus
when using the Histone H3 as a baseline
comparison?
METHODS
PCR Amplification
Cloning using an E. coli strain
Plasmid Prep (DNA Extraction)
Sequencing of DNA (Plasmid)
Analysis
REFERENCES
Charles T. Bryson, USDA Agricultural Research, Bugwood.org
Cronn R.C., Small, R. L. Haselkorn, Tamara, Wendel, J.F. (2002) Rapid
Diversification of the Cotton Genus (Gossypium: Malvaceae) Revealed By
Analysis of Sixteen Nuclear and Chloroplast Genes. American Journal of
Botany 89(4), 707-725
Talbert, Paul B. Masuelli Ricardo, Tyagi Anand P. Comai, Lucas and Steven
Henikoff (May 2002) Centromeric Localization and Adaptive Evolution of an
Arabidopsis Histone H3 Variant. The Plant Cell 14, 1227-1238
RESULTS
Cloning technigues successful.
Plasmid isolation successful
Sequencing not so successful.
Second time sequencing not successful.
Third time sequencing not successful.
Problem solve. Try again. Keep fingers crossed.
ACKNOWLEDGEMENTS
I would like to thank the Plant Genomics Outreach Program including
Adah Leshem-Ackerman and Jonathan Wendel for the opportunity to
participate in the RET program. I would especially like to thank Ryan
Rapp and Ryan Percifield for their mentoring, patience and
willingness to put up with me in the lab. I would also like to thank the
Biotechnology Outreach Education Center and the Office of
Biotechnology as well as the NSF for funding this program.