Plasma Membrane Recruitment Patterns of Glucose Transporters (GLUT) 1, 2, 3, and 5 in Response to Feeding in the Ruby-throated Hummingbird, Archilochus colubris.
Year: 2018
Type: dissertation
Abstract: Hummingbirds, among the smallest vertebrate endotherms, have high resting and active metabolic rates and subsist almost exclusively on nectar sugar; they face extreme challenges to energy homeostasis and blood sugar regulation. Transmembrane sugar transport, and thus some control over energy flux, is mediated by facilitative glucose transporters, GLUTs. I determined relative protein abundance and subcellular localization via Western Blot for several GLUTs in flight muscle and liver from fed or fasted ruby-throated hummingbird (Archilochus colubris). I observed GLUT5 protein in flight muscle PM, consistent with its hypothesized uniquely high flux of fructose. GLUT1 protein was absent in hepatocytes, contradicting previously observations of transcript. Finally, glucose-specific GLUT1 abundance was increased in flight muscle PM of fed birds, while liver PM was increased in GLUT3 and glucose/fructose-transporting GLUT2. This suggests muscle glucose uptake capacity is dynamically regulated in response to feeding, while both glucose- and fructose-uptake capacity respond in the liver.
Source: TSpace (University of Toronto)
Author: Raafay Syed Ali
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2901489269