Lipidomics pp 217-229 | Cite as
Isoprenylation of Monomeric GTPases in Human Trabecular Meshwork Cells
Abstract
Small monomeric GTPases, including those belonging to the Rho family, regulate a diverse array of intracellular signaling pathways which affect vesicle transport/trafficking, endocytosis, cell cycle progression, cell contractility, and formation of stress fibers or focal adhesions. Functional activation of newly synthesized small monomeric GTPases is facilitated by a multistep post-translational process involving transferase-catalyzed addition of farnesyl or geranylgeranyl isoprenoids to conserved cysteine residues within a unique carboxy terminal CaaX motif. Here, using well-established and widely available contemporary methodologies, detailed protocols by which to semi-quantitatively evaluate the functional consequence of post-translational isoprenylation in human trabecular meshwork cells are described. We introduce the concept that isoprenylation alone is itself a key regulator of mammalian Rho GTPase expression and turnover.
Key words
Farnesyl Geranylgeranyl Human Trabecular meshwork Monomeric GTPaseNotes
Acknowledgements
The author thanks Mr. Jonathan Lautz for helpful comments and discussion. This work was supported, in part, by grants from the Department of Veterans Affairs, National Institutes of Health, the Midwest Eye-Banks (Eversight), the Illinois Society for the Prevention of Blindness, and the Richard A. Peritt Charitable Foundation.
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