RedcGull is a genetically encoded fluorescent sensor for cGMP. It is based on the cGMP-binding domain of the Mus musculus Pde5a gene (MGI:MGI:2651499); this domain (flanked by linkers) has been inserted into mApple between residues 150-151, and a number of additional mutations have also been introduced during optimization of the sensor (PMID:36064581).
