IN SILICO ANALYSIS OF ZEBRAFISH LEPTIN-A KNOCKDOWN GENE EXPRESSION DATA
REVEALS ENRICHMENT FOR METABOLIC AND DEVELOPMENTAL PATHWAYS INCLUDING
MORPHOLINO ARTIFACTS
A Thesis
Presented to
The Graduate Faculty of The University of Akron
In Partial Fulfillment
of the Requirements for the Degree
Master of Science
Matthew Tuttle
May, 2017
IN SILICO ANALYSIS OF ZEBRAFISH LEPTIN-A KNOCKDOWN GENE EXPRESSION DATA
REVEALS ENRICHMENT FOR METABOLIC AND DEVELOPMENTAL PATHWAYS INCLUDING
MORPHOLINO ARTIFACTS
Matthew Tuttle
Thesis
Approved: Accepted:
______Faculty Advisor Dean of the College Dr. Richard Londraville Dr. John Green
______Faculty Reader Dean of the Graduate School Dr. Qin Liu Dr. Chand Midha
______Faculty Reader Date Dr. Joel Duff
______Department Chair Dr. Stephen Weeks
ii
ABSTRACT
Mammalian leptin (LEP) is a pleiotropic peptide hormone best characterized for its roles related to obesity and diabetes. However, the molecular function of the leptin signal transduction pathway in non-mammals is less clear. Comparative studies that address leptin signaling in non-model organisms are integral components of the leptin phylogenetic history, and there is little evidence addressing the functional disparities between the teleost leptin paralogues and mammalian leptins. To demarcate genes and biochemical pathways regulated by leptin signaling in developing zebrafish, microarray gene expression data were generated with total RNA isolated at 48 hours post fertilization from leptin-a orpholi o oligo u leotide k o kdow , re o i a t leptin-a res ue , a d wild t pe e ryos. Expression estimates were computed for
26,046 genes across 16 microarray samples. Differentially expressed genes (DEG),
(KEGG) pathways, and Gene Ontologies (GO) were evaluated for three contrasts
(Morphant:Control, Rescue:Morphant, Rescue:Control).
Signaling pathways that respond to leptin-a knockdown and rescue are analogous to gene targets of the mammalian LEP system ( G RH , MAPK ,