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Updated: Oct 19, 2026

Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay
Published on: November 11, 2018
GTPase and transglutaminase are associated in the secretion of the rat anterior prostate
A M Spina1, C Esposito, M Pagano
1Department of Biochemistry and Biophysics, 2nd University of Naples, via Costantinopoli 16, Naples, 80138, Italy.
Abstract:
We have found that in the secretion of rat anterior prostate, a hydrolyzing activity on GTP is present with a high affinity for the substrate; ATP, GDP, and ADP are not substrates for enzymatic activity. At the same time we have shown that GTP is a negative modulator for the well-known type IV transglutaminase activity present in the prostatic secretion. The hydrolyzing activity on GTP appears to be due to two molecular species: a high-molecular-weight GTPase, having electrophoretical mobility higher than 100 kDa, and a low-molecular-weight GTPase, of about 30 kDa. The two enzymatic activities are associated in the prostatic secretion with the transglutaminase (type IV). We describe an experimental procedure to separate them.
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