|-B.S., Southwest Texas State University
-M.S., Texas A&M University
-Ph.D., Cornell University
Office: 304 Oliphant
Phone: (918) 631-2758
There are two main research foci in my lab, both reflecting different
facets of the general topic of molecular evolution.
One uses the gene-enzyme system arginine kinase in Drosophila melanogaster to investigate functional constraints
that may regulate rate of molecular change. This enzyme is a protein that is evolving even more slowly than the
vertebrate homolog creatine kinase. One critical genetic difference between the two systems is that the vertebrate
enzyme is encoded by multiple loci each exhibiting tissue or cell compartment specificity. In contrast, the Drosophila
system is encoded by a single locus yet is expressed in a similar array of tissues and subcellular compartments
as the vertebrate homologs. We are testing the obvious hypothesis of multiple functions constraining the rate of
amino acid substitutions by critically examining the multiple roles of arginine kinase in various tissues in combination
with saturation mutagenesis and molecular characterization of resulting mutants.
The second research focus in the lab is the development of a comprehensive molecular phylogeny for fishes of the
order Cyprinodontidae, commonly known as killifishes. These fishes are distributed throughout the tropics and some
temperate regions world wide. Some species display a unique life history trait called annualism, a complex suite
of traits involving modified reproductive behavior and developmental diapauses that result in an ability to live
in marginal habitats. Some members of the group also exhibit extreme examples of karyotypic modification. The molecular
phylogenies we have developed have revealed new insights into the evolution of complex traits, the phylogenetic
context of chromosomal evolution and new insights into the biogeography of the group
- Biol 1504-Biology of Populations
- Biol 3123-Advanced Genetics
- Biol 4213-Molecular Evolution
- Biol 4253-Human Genetics
- Murphy, W.J., Thomerson, J.E. and G.E. Collier, 1999. Phylogeny of the
neotropical killifish family Rivulidae (Cyprinodontiformes, Aplocheiloidea) inferred from mitochondrail DNA sequences.
Mol. Phyl. Evol. 13:289-301.
- Murphy, W.J., and G.E. Collier, 1999. Phylogenetic relationships of African
killifishes in the genera Aphyosemion and Fundulopanchax inferred from mitochondrial DNA sequences. Mol. Phyl.
- Murphy, W.J., T.N.P. Nguyen, E.B. Taylor and G.E. Collier, 1999. Mitochondrial
DNA phylogeny of West African aplocheiloid killifishes (Cyprinodontiformes, Aplocheilidae). Mol. Phyl. Evol 11:343-350.
- Chien, Y.C. and G.E. Collier. 1997. Biochemical comparison of arginine
kinase allozymes in Drosophila melanogaster. Zool. Studies 35(4):277-287.
- Murphy, W.J. and G.E. Collier, 1997. A molecular phylogeny for aplocheiloid
fishes (Atherinomorpha, Cyprinodontiformes): The role of vicariance and the origins of annualism. Mol. Biol. Evol.
- Murphy, W.J. and G.E. Collier, 1996. Phylogenetic relationships within
the Aplocheiloid fish genus Rivulus (Cyprinodontiformes, Rivulidae): Implications for Caribbean and Central American
biogeography. Mol. Biol. Evol. 13:642-649.
- James, J. M. and G. E. Collier, 1992. Early gene interaction during prepupal
expression of Drosophila arginine kinase. Dev. Genet. 13:302-305.
- James, J. M. and G. E. Collier, 1990. Hormonally regulated expression
of arginine kinase in Drosophila melanogaster. Roux's Arch. Develop. Biol. 198:474-478.
- Collier, G. E., 1990. Molecular evolution of arginine kinase within the
genus Drosophila. J. Hered. 81:177-182.
Research Students and Projects:
- Carol Cox (Ph.D. candidate): Ecdysone regulated expression of arginine
kinase in Drosophila melanogaster prepupae.
- Mike Expinoza (M.S. candidate): Phylogeography of Central American Rivulus
- Donna McDonnel (undergraduate student, TURC): Phylogeography of Central
American livebearers (Cyprinodontiformes, Poecilidae)
- Nicole Farar (undergraduate student, TURC): Mutagenesis and sequence analysis
of Drosophila arginine kinase.
- Emily Scott (undergraduate student): Clonal analysis of arginine kinase
function in Drosophila melanogaster.
- Chair, IACUC
- Director, Mervin Bovaird Center for Molecular Biology and Biotechnology
- Member, Health Research Committee, Oklahoma Center for the Advancement
of Science and Technology