Insights into the in vivo regulation of glutamate dehydrogenase from the foot muscle of an estivating land snail

Bell, R. A.V., Dawson, N. J. and Storey, K. B. (2012) Insights into the in vivo regulation of glutamate dehydrogenase from the foot muscle of an estivating land snail. Enzyme Research, 2012, 317314. (doi: 10.1155/2012/317314) (PMID:22536484) (PMCID:PMC3318891)

Abstract

Land snails, Otala lactea, survive in seasonally hot and dry environments by entering a state of aerobic torpor called estivation. During estivation, snails must prevent excessive dehydration and reorganize metabolic fuel use so as to endure prolonged periods without food. Glutamate dehydrogenase (GDH) was hypothesized to play a key role during estivation as it shuttles amino acid carbon skeletons into the Krebs cycle for energy production and is very important to urea biosynthesis (a key molecule used for water retention). Analysis of purified foot muscle GDH from control and estivating conditions revealed that estivated GDH was approximately 3-fold more active in catalyzing glutamate deamination as compared to control. This kinetic difference appears to be regulated by reversible protein phosphorylation, as indicated by ProQ Diamond phosphoprotein staining and incubations that stimulate endogenous protein kinases and phosphatases. The increased activity of the high-phosphate form of GDH seen in the estivating land snail foot muscle correlates well with the increased use of amino acids for energy and increased synthesis of urea for water retention during prolonged estivation.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Dawson, Dr Neal
• Authors: Bell, R. A.V., Dawson, N. J., and Storey, K. B.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Enzyme Research
• Publisher: Hindawi
• ISSN: 2090-0406
• ISSN (Online): 2090-0414
• Copyright Holders: Copyright © 2012 Ryan A.V. Bell et al.
• First Published: First published in Enzyme Research 2012: 317314
• Publisher Policy: Reproduced under a Creative Commons License