Importance of a Putative Glucose Transporter during Physiological Stress in the Wood Frog, Rana sylvatica


Meeting Abstract

P1.201  Wednesday, Jan. 4  Importance of a Putative Glucose Transporter during Physiological Stress in the Wood Frog, Rana sylvatica ROSENDALE, A.J.*; COSTANZO, J.P.; LEE, R.E.; Miami University, Oxford OH; Miami University, Oxford OH; Miami University, Oxford OH rosendaj@muohio.edu

Survival of physiological stresses such as freezing and dehydration by the terrestrial wood frog, Rana sylvatica, involves accumulation of high levels of glucose in tissues and body fluids. Stresses R. sylvatica is able to tolerate due in part to increased glucose levels include dehydration, freezing, and anoxia. Hyperglycemia is achieved by the production of large quantities of glucose in the liver, and the rapid export of glucose from the liver to the body fluids. The latter process is thought to involve facilitative glucose transporters, specifically GLUT2; however, little is known about how changes in GLUT2 expression in response to physiological stress may contribute to the survival of anurans during physiological stress. To elucidate the importance of GLUTs during physiological stress, we first identified a GLUT2 homolog from R. sylvatica. The GLUT2 cDNA cloned from liver encodes a 498 amino acid protein which has a high degree of identity to GLUT2 proteins from other taxa. GLUT2 expression in response to organismal dehydration and freezing, as well as exposure to anoxic conditions, was analyzed using quantitative PCR. Preliminary findings suggest that physiological stress results in changes in GLUT2 expression in R. sylvatica; therefore, GLUT2 abundance in liver may mediate stress-induced glucose accumulation. Results of this study begin to clarify the importance of GLUTs in the physiological regulation of glucose in amphibians. Supported in part by NSF IOS1022788.

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