In high school you probably learned that the nucleus, chloroplast, and mitochondrian came into existence through endosymbiotic events— i.e., that one cell engulfed two others and now the three cells rely on each other for survival as a single plant cell. This lab is designed to let you test this hypothesis.
Chloroplasts are only found in eukaryotic algae, leaves and other green plant organs. They are the photosynthetic organelles in plants that harvest light energy and convert it to chemical energy for growth and other vital functions. The chloroplasts do not produce energy for (ATPs) the cell, however. Through the process of photosynthesis, they produce the raw materials that the mitochondria use in the process of cellular respiration.
Mitochondria, on the other hand, are found in almost all eukaryotic cells. Not only are they much more efficient at generating ATP that are the fermentation pathways in the cytosol, by uncoupling or coupling electron transport from oxidative phosphorylation, they are the primary regulator of heat productionin cells.
Nuclear DNA refers to the DNA that has become trapped within the nucleus of eukaryotic cells. This is one of the defining features separating prokaryotic organisms from eukaryotic organisms.
Data for Workbench Practice
Phylogenetic Profiling (Rubisco)
Phylogenetic profiling involves generating and comparing multiple phylogenies to look for similarities and differences across species and molecules. http://www.doe-mbi.ucla.edu/People/Yeates/Gallery/phylo_profile.html
The following datasets are available:
Developing phylogenies from 3-genomes
Barkman TJ, Chenery G, McNeal JR, Lyons-Weiler J, Ellisens WJ, Moore
G, Wolfe AD, dePamphilis CW.
Chaw SM, Parkinson CL, Cheng Y, Vincent TM, Palmer JD.
Deep Green Challenges
A tradition in the computer science, information technology, and mathematical communities is to issue "challenges." Such challenges pose problems to fellow scientists, and provide an entertaining way to advance the discipline. Because the concept of challenges has not been widely applied in the life sciences, we hope that introducing them will promote additional interactions among the biological and analytical communities. http://www.life.umd.edu/labs/delwiche/deepgreen/DGchallenges.html
Origins of plastids
Collect a set of sequences to test a hypothesis about chloroplast and mitochondria evolution. We have lots of references to get you started.
Peeters_2000.pdf (1.5 mb)
Pellegrini_1999.pdf (105 kb)
Marcotte_2000.pdf (556 kb)
Grey_1999.pdf (177 kb)
Delwiche_1999.pdf (544 kb)
Delwiche_1995.pdf (2.46 mb)