Protein / target

Guanylate cyclase soluble subunit alpha-2

GUCY1A2P33402Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
10
Approved medicines
30
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

Guanylate cyclase activity

Strongest disease association

hypertensive disorder

Genetic evidence · score 0.59

Therapeutic maturity

Clinically validated target

10 approved medicines against this target

Druggability

Small molecule

Open Targets tractability · Approved Drug

Clinical development

10 approved · 5 in clinical development

30 linked trials

Derived from structured UniProt, Open Targets and literature data on this page.

Protein profile

UniProt 2026_02

Canonical identity and biological annotation from UniProt.

Function

Alpha subunit of soluble guanylate cyclase (sGC), a central enzyme in nitric oxide (NO) signaling. Functions as the main intracellular receptor for NO. Upon NO binding, catalyzes the conversion of GTP to cyclic GMP (cGMP) and thereby transducing NO signal into a ubiquitous intracellular second messenger

Subcellular location

Cytoplasm, cytosol
Domains and Gene Ontology detail (10)

Domains & features

H-NOXGuanylate cyclase

Gene Ontology

  • Ccytosol
  • Cguanylate cyclase complex, soluble
  • FGTP binding
  • Fguanylate cyclase activity
  • Fheme binding
  • Pintracellular signal transduction
  • Presponse to oxygen levels
  • Psignal transduction

732 aa · 82 kDa · 3 isoforms

Biological roles

Reactome v97

What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.

Muscle contractionReactome
View supporting evidence

Muscle contraction

  • ·Smooth Muscle Contraction
View underlying pathways (2)

Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.

Interaction neighbourhood

STRING v12.0

Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.

GUCY1B1GUCY1A1PRKG2PRKG1NOS1ITPAPKMENPP1ENPP3NUDT2GUCY1A2

10 strongest partners — larger node and heavier line mean higher confidence

Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.

Drugs targeting this protein

2

Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.

Nitric Oxide
ApprovedActivator

Soluble guanylate cyclase activator

Appears in clinical studies involving pulmonary arterial hypertension, respiratory failure, pulmonary hypertension, Hypertension

Acts on a complex — shared with GUCY1B1, GUCY1B2, GUCY1A1 · 1 of 4 recorded protein targets

riociguat
ApprovedPositive allosteric modulator

Soluble guanylate cyclase positive allosteric modulator

Appears in clinical studies involving chronic thromboembolic pulmonary hypertension, pulmonary arterial hypertension, hypertensive disorder, pulmonary hypertension

Acts on a complex — shared with GUCY1B1, GUCY1B2, GUCY1A1 · 1 of 4 recorded protein targets

ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.

Translational evidence

Open Targets 26

Why this target matters therapeutically — disease associations, drugs in development, tractability and safety, from Open Targets.

Strongest genetic associations

Human genetic evidence — the most direct causal link between this target and a disease.

hypertensive disorder0.59

Genetic · overall 0.65

coronary artery disorder0.50

Genetic · overall 0.68

cardiovascular disorder0.39

Genetic · overall 0.63

Highest-confidence therapeutic associations

Diseases where a drug acting on this target has already reached clinical development.

angina pectoris0.99

Clinical · overall 0.60

heart failure0.96

Clinical · overall 0.58

pulmonary arterial hypertension0.95

Clinical · overall 0.58

pulmonary hypertension0.92

Clinical · overall 0.56

myocardial infarction0.91

Clinical · overall 0.55

Highest overall evidence

Remaining associations by Open Targets' aggregated evidence score.

chronic thromboembolic pulmonary hypertension0.53

Clinical

respiratory failure0.52

Clinical

Show all associations
coronary artery disorder0.68
hypertensive disorder0.65
cardiovascular disorder0.63
angina pectoris0.60
heart failure0.58
pulmonary arterial hypertension0.58
pulmonary hypertension0.56
myocardial infarction0.55
chronic thromboembolic pulmonary hypertension0.53
respiratory failure0.52

Open Targets ranks 207 associations for this target and we store the top 10 by aggregated score. The long tail is largely literature co-mention and RNA-expression evidence, not evidence that this target drives those diseases.

Known drugs · 15 total

PENTAERYTHRITOL TETRANITRATEApproval

cardiovascular disorder · angina pectoris · type 2 diabetes mellitus

RUNCACIGUATPhase 2

chronic kidney disease · non-proliferative diabetic retinopathy · diabetes mellitus

SODIUM NITROPRUSSIDEApproval

hemorrhage · congestive heart failure · Hypertension

CINACIGUATPhase 2

heart failure

ISOSORBIDE DINITRATEApproval

angina pectoris · coronary artery disorder · cardiovascular disorder

ATACIGUATPhase 2 3

neuropathic pain · peripheral arterial disease

NITROPRUSSIDEApproval

hypertensive disorder · Hypertension · myocardial infarction

NITROGLYCERINApproval

angina pectoris · coronary artery disorder · heart failure

NITRIC OXIDEApproval

pulmonary arterial hypertension · respiratory failure · pulmonary hypertension

OLINCIGUATPhase 2

Achalasia · sickle cell disease

Tractability

SM · Approved DrugSM · High-Quality LigandSM · Druggable FamilyPR · Database UbiquitinationPR · Half-life Data

Clinical trials

30

Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.

Show remaining trials (24)

COMPLETED · via Nitric Oxide · NCT00987207

ClinicalTrials.gov via the drug-target graph.

Forefront confidence

Synthesis

Our own weighting of the evidence behind each disease association. Human genetics and clinical evidence count for most; literature co-mention counts for little, because two entities sharing an abstract is not evidence that one drives the other.

hypertensive disorderWell supported
0.88
agreement 0.770.98
Clinical54%Genetic46%Literature1%

Open Targets aggregate 0.65 · 3 independent evidence families

coronary artery disorderWell supported
0.87
agreement 0.770.97
Clinical60%Genetic40%

Open Targets aggregate 0.68 · 2 independent evidence families

cardiovascular disorderWell supported
0.82
agreement 0.710.93
Clinical64%Genetic36%Literature1%

Open Targets aggregate 0.63 · 3 independent evidence families

angina pectorisModerately supported
0.74
agreement 0.580.91
Clinical100%

Open Targets aggregate 0.60 · 1 independent evidence family

heart failureModerately supported
0.72
agreement 0.560.87
Clinical99%Literature1%

Open Targets aggregate 0.58 · 2 independent evidence families

This ranking differs from Open Targets' own: re-weighting moves genetically-evidenced diseases above more heavily co-mentioned ones. The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the underlying per-type scores are shown above so the calculation can be checked.

What's happening now

33

Recent activity around this target, drawn from one canonical event stream. Every item is reached through 2 drugs that target this protein, so each event is news about that drug rather than about the protein directly.

  1. CHMP positive opinion2026-07-20

    CHMP positive opinion: Riociguat Accord (EMA)

    ema · regulatory · ema · via riociguat

  2. New publication2025-04-08
    Understanding chronic inflammation: couplings between cytokines, ROS, NO, Ca<sub>i</sub> <sup>2+</sup>, HIF-1α, Nrf2 and autophagy.

    Frontiers in immunology · 2025 · 37 citations · Europe PMC · via Nitric Oxide

  3. New publication2025-01-01
    Neurological Manifestations Following Traumatic Brain Injury: Role of Behavioral, Neuroinflammation, Excitotoxicity, Nrf-2 and Nitric Oxide.

    CNS & neurological disorders drug targets · 2025 · 5 citations · Europe PMC · via Nitric Oxide

  4. New publication2024-12-11
    Systemic and Cardiac Microvascular Dysfunction in Hypertension.

    International journal of molecular sciences · 2024 · 34 citations · Europe PMC · via Nitric Oxide

  5. New publication2024-08-21
    The Unexpected Role of the Endothelial Nitric Oxide Synthase at the Neurovascular Unit: Beyond the Regulation of Cerebral Blood Flow.

    International journal of molecular sciences · 2024 · 12 citations · Europe PMC · via Nitric Oxide

  6. New publication2024-07-25
    Ca<sup>2+</sup>-dependent phosphodiesterase 1 regulates the plasticity of striatal spiny projection neuron glutamatergic synapses.

    Cell reports · 2024 · 6 citations · Europe PMC · via Nitric Oxide

  7. New publication2024-03-14
    Several lines of antioxidant defense against oxidative stress: antioxidant enzymes, nanomaterials with multiple enzyme-mimicking activities, and low-molecular-weight antioxidants.

    Archives of toxicology · 2024 · 563 citations · Europe PMC · via Nitric Oxide

  8. New publication2024-02-20
    A multidisciplinary study on Clinostomum infections in Nile tilapia: micro-morphology, oxidative stress, immunology, and histopathology.

    BMC veterinary research · 2024 · 12 citations · Europe PMC · via Nitric Oxide

  9. New publication2023-09-19
    Neuronal Nitric Oxide Synthase and Post-Translational Modifications in the Development of Central Nervous System Diseases: Implications and Regulation.

    Molecules (Basel, Switzerland) · 2023 · 12 citations · Europe PMC · via Nitric Oxide

  10. New publication2023-09-16
    Modulation of the nitric oxide/cGMP pathway in cardiac contraction and relaxation: Potential role in heart failure treatment.

    Pharmacological research · 2023 · 24 citations · Europe PMC · via Nitric Oxide

  11. New publication2020-02-22
    Vitamin D and Endothelial Function.

    Nutrients · 2020 · 216 citations · Europe PMC · via Nitric Oxide

  12. New publication2020-02-04
    Nitric oxide orchestrates metabolic rewiring in M1 macrophages by targeting aconitase 2 and pyruvate dehydrogenase.

    Nature communications · 2020 · 369 citations · Europe PMC · via Nitric Oxide

Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.