Recombinant human PDE5A/PDE5 protein

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

PDE5A also known as PDE5 or phosphodiesterase type 5 plays a critical role in hydrolyzing cyclic guanosine monophosphate (cGMP) to its inactive form. This enzyme is part of the phosphodiesterase family and has a molecular mass of approximately 100 kDa. PDE5A is expressed mainly in the smooth muscle cells of blood vessels and in the corpus cavernosum of the penis. Other expression sites include the lung heart and skeletal muscle.

Biological function summary

PDE5A regulates intracellular levels of cGMP an important secondary messenger in various signaling pathways. It is not part of a large protein complex but directly influences the contractility of smooth muscle tissues. By controlling cGMP levels PDE5A modulates vascular tone and influences processes such as vasodilation. This regulation is essential for maintaining a balance in the contractile state of muscles impacting blood flow and other vital functions.

Pathways

PDE5A contributes significantly to the nitric oxide (NO)-cGMP signaling pathway which is important for vascular relaxation. In this pathway nitric oxide stimulates guanylate cyclase to produce cGMP which then activates specific kinases and ion channels. Related proteins such as guanylate cyclase and cGMP-dependent protein kinases work alongside PDE5A to mediate smooth muscle relaxation and vasodilation particularly in penile erectile tissue.

PDE5A shows strong connections to erectile dysfunction and pulmonary hypertension. In the case of erectile dysfunction impaired regulation of cGMP by PDE5A affects the relaxation of smooth muscle leading to inadequate blood flow. Pulmonary hypertension involves elevated blood pressure in the lung arteries which PDE5A influences through its role in controlling vascular tone. The enzyme guanylate cyclase associates closely with PDE5A in these contexts as both influence cGMP pathways involved in these conditions.