The function of Ensembl gene identifier ENSG00000160191 (PDE9A, phosphodiesterase 9A) is as follows. Specifically hydrolyzes the second messenger cGMP, which is a key regulator of many important physiological processes. Highly specific: compared to other members of the cyclic nucleotide phosphodiesterase family, has the highest affinity and selectivity for cGMP (PubMed:18757755, PubMed:21483814, PubMed:9624146). Specifically regulates natriuretic-peptide-dependent cGMP signaling in heart, acting as a regulator of cardiac hypertrophy in myocytes and muscle. Does not regulate nitric oxide-dependent cGMP in heart (PubMed:25799991). Additional experiments are required to confirm whether its ability to hydrolyze natriuretic-peptide-dependent cGMP is specific to heart or is a general feature of the protein (Probable). In brain, involved in cognitive function, such as learning and long-term memory (By similarity). {ECO:0000250|UniProtKB:Q8QZV1, ECO:0000269|PubMed:18757755, ECO:0000269|PubMed:21483814, ECO:0000269|PubMed:25799991, ECO:0000269|PubMed:9624146, ECO:0000305}.