Guanylyl Imidodiphosphate is a stimulator of adenylate cyclase.

Adenylyl cyclase, also commonly known as adenyl cyclase and adenylate cyclase, is an enzyme with key regulatory roles in essentially all cells. Adenylyl cyclase is the most polyphyletic known enzyme.

In vitro: A previous study evaluated the properties of microtubules formed in the presence of GTP, 5'-guanylyl imidodiphosphate, and 5'-guanylyl methylenediphosphate to identify features of the assembly or disassembly reactions related to hydrolysis. Results showed that the assembly of microtubules with GTP or 5'-guanylyl imidodiphosphate was similar in rates and extents of assembly, the length distributions, as well as the podophyllotoxin-induced depolymerization. The greater rapidity of 5'-guanylyl methylenediphosphate-supported assembly, however, led to shorter, more numerous microtubules and the rate of podophyllotoxin-induced depolymerization was consistent with an increased number of concentration of microtubules. In addition, it was found that GTP-tubule turnover corresponded to a rate of around 8% of the microtubule protein taken up or released per hour. Moreover, with 5'-guanylyl imidodiphosphate- and 5'-guanylyl methylenediphosphate-tubules, the rates of label uptake by unlabeled microtubules were significantly lower than that observed with guanosine triphosphate [1].

In vivo: Currently, there is no animal in vivo data reported.

Clinical trial: So far, no clinical study has been conducted.

Reference:
[1] B.  J. Terry and D. L. Purich. Assembly and disassembly properties of microtubules formed in the presence of GTP, 5'-guanylyl imidodiphosphate, and 5'-guanylyl methylenediphosphate. The Journal of Biological Chemisty 255(21), 10532-10536 (1980).