Students in The Python Project perform experiments in parallel with a larger project in the Leinwand Lab at University of Colorado at Boulder that examines the biological mechanisms that regulate organ hypertrophy in Burmese pythons after feeding. To manage the systemic stress associated with digesting meals that can reach up to half of their body weight, pythons undergo several extraordinary physiological changes: dramatic increases in oxygen consumption, an extreme decrease in the pH of the stomach, and significant hypertrophy of many organs. For example, the mass of the ventricle of a python heart can increase up to 40% in as little as 48 hours after feeding relative to that of a fasting python, a change that is accompanied by a 40-fold increase in metabolic rate. The sponsor laboratory and others have also observed increases in liver mass that are attributable to an increase in proliferation rather than hypertrophy of hepatic cells. Rapid growth of the python heart and liver after feeding, therefore, provides a unique opportunity to examine the molecular mechanisms responsible for organ growth in terms of expression of genes related to hypertrophy and hyperplasia, respectively.
Students in The Python Project examine expression of a set of candidate genes thought to be involved in organ growth or other extreme physiological processes in the Burmese python, based on studies in rodents and humans. Students isolate RNA from python organs, synthesize cDNA, design PCR primers based on cDNA sequence available from a related species [chicken, (Gallus gallus)], and perform quantitative PCR to measure changes in gene expression. In addition, students perform a variety of in vitro and in silico validations from beginning to end. This challenging approach is necessary because the python genome has not yet been annotated.