Morehead State University
Phylogeny of Esocids Based on Beta-actin and a Minisatellite in the Growth Hormone Gene
Institution
Morehead State University
Faculty Advisor/ Mentor
David Peyton
Abstract
The phylogeny of Esociformes (pikes, pickerels, and mudminnows) has recently been examined at the molecular level to establish the validity of morphological classification schemes. Mitochondrial and nuclear genes have been examined by other groups to arrive at a consensus for the evolution of this somewhat problematic group. We have approached this question using molecular data from two nuclear genes: cytoplasmic beta-actin and growth hormone. Beta-actin is highly conserved at the amino acid level among all vertebrates, and was cloned by polymerase chain reaction from each of the five esocids using consensus primers that correspond to the first and last nine codons of the gene. The amino acid coding sequences and intron junctions were deduced from the complementary DNA of beta-actin from E. masquinongy. In addition, a minisatellite sequence of 33 nucleotides was discovered in the fourth intron of the growth hormone gene in each of the five esocids. This 33 nucleotide sequence is present in multiple copies in each esocid, but only occurs once in the salmonids. The minisatellite does not show variability within species, and may provide another tool to establish the relatedness of the esocids to other taxa.
Phylogeny of Esocids Based on Beta-actin and a Minisatellite in the Growth Hormone Gene
The phylogeny of Esociformes (pikes, pickerels, and mudminnows) has recently been examined at the molecular level to establish the validity of morphological classification schemes. Mitochondrial and nuclear genes have been examined by other groups to arrive at a consensus for the evolution of this somewhat problematic group. We have approached this question using molecular data from two nuclear genes: cytoplasmic beta-actin and growth hormone. Beta-actin is highly conserved at the amino acid level among all vertebrates, and was cloned by polymerase chain reaction from each of the five esocids using consensus primers that correspond to the first and last nine codons of the gene. The amino acid coding sequences and intron junctions were deduced from the complementary DNA of beta-actin from E. masquinongy. In addition, a minisatellite sequence of 33 nucleotides was discovered in the fourth intron of the growth hormone gene in each of the five esocids. This 33 nucleotide sequence is present in multiple copies in each esocid, but only occurs once in the salmonids. The minisatellite does not show variability within species, and may provide another tool to establish the relatedness of the esocids to other taxa.