All Pathways
Curated Pathways103
Glycolysis
The breakdown of glucose into pyruvate, yielding ATP and NADH.
Citric Acid Cycle (Krebs Cycle)
Oxidizes acetyl-CoA to CO₂, generating GTP, NADH, and FADH₂.
Oxidative Phosphorylation
Electron transport chain coupled to ATP synthesis via chemiosmosis.
Pentose Phosphate Pathway
Generates NADPH and ribose-5-phosphate for biosynthesis.
β-Oxidation of Fatty Acids
Sequential removal of 2-carbon units from fatty acids as acetyl-CoA.
Photosynthesis – Light Reactions
Capture of light energy to produce ATP and NADPH, with O₂ as a byproduct.
Calvin Cycle (Light-Independent Reactions)
Fixes CO₂ into organic molecules using ATP and NADPH from light reactions.
Gluconeogenesis
Synthesis of glucose from non-carbohydrate precursors.
Glycogen Metabolism
Synthesis and degradation of glycogen for glucose storage and release.
Urea Cycle
Converts toxic ammonia to urea for excretion.
Amino Acid Catabolism
Degradation of amino acids to metabolic intermediates and ammonia.
Nucleotide Biosynthesis
De novo and salvage pathways for purine and pyrimidine nucleotide production.
Folate / One-Carbon Metabolism
Transfer of one-carbon units for nucleotide synthesis, methylation, and amino acid metabolism.
Heme Biosynthesis
Eight-step pathway producing heme from glycine and succinyl-CoA.
Ketogenesis
Hepatic production of ketone bodies from excess acetyl-CoA during fasting.
Fermentation (Anaerobic)
Regeneration of NAD⁺ from NADH under anaerobic conditions.
Glyoxylate Cycle
Net conversion of acetyl-CoA to oxaloacetate, bypassing CO₂ loss steps of TCA.
Nitrogen Fixation
Reduction of atmospheric N₂ to ammonia by nitrogenase.
CAM Photosynthesis
Temporal separation of CO₂ fixation (night) and Calvin cycle (day) to conserve water.
C4 Photosynthesis
Spatial separation of initial CO₂ fixation and Calvin cycle to concentrate CO₂.
MAPK/ERK Pathway
RAS–RAF–MEK–ERK cascade transducing growth factor signals to the nucleus.
PI3K/AKT/mTOR Pathway
Regulates cell survival, growth, and metabolism via phosphoinositide signaling.
Wnt/β-Catenin Pathway
Controls cell fate, proliferation, and polarity through β-catenin stabilization.
Notch Signaling Pathway
Juxtacrine signaling controlling cell fate decisions via proteolytic receptor activation.
JAK-STAT Pathway
Cytokine-driven signaling from receptor to gene expression via STAT dimerization.
NF-κB Pathway
Master regulator of inflammation, immunity, and cell survival.
Insulin Signaling Pathway
Insulin receptor activation driving glucose uptake and anabolic metabolism.
G Protein-Coupled Receptor (GPCR) Signaling
Seven-transmembrane receptors activating heterotrimeric G proteins.
Calcium Signaling
Ca²⁺ as a universal second messenger controlling diverse cellular processes.
AMPK Pathway
Cellular energy sensor activating catabolic and inhibiting anabolic pathways.
cAMP/PKA Signaling
Cyclic AMP as a second messenger activating protein kinase A.
Hippo Signaling Pathway
Organ size control pathway regulating cell proliferation and apoptosis.
VEGF Signaling (Angiogenesis)
Vascular endothelial growth factor driving new blood vessel formation.
DNA Replication
Semi-conservative duplication of the genome before cell division.
Transcription
Synthesis of RNA from a DNA template by RNA polymerase.
Translation (Protein Synthesis)
Ribosome-mediated synthesis of polypeptides from mRNA templates.
DNA Repair Pathways
Multiple mechanisms to detect and correct DNA damage.
Epigenetic Regulation
Heritable changes in gene expression without altering the DNA sequence.
RNA Processing & Splicing
Post-transcriptional modifications converting pre-mRNA to mature mRNA.
RNA Interference (RNAi)
Post-transcriptional gene silencing by small interfering RNAs.
Protein Folding & Quality Control
Chaperone-assisted folding and ER quality control of newly synthesized proteins.
Cell Cycle Regulation
Ordered progression through G1, S, G2, and M phases via cyclin-CDK complexes.
Mitosis
Nuclear division producing two genetically identical daughter nuclei.
Meiosis
Two successive divisions producing four haploid gametes with genetic diversity.
Cell Cycle Checkpoints
Surveillance mechanisms ensuring genomic integrity at each cell cycle phase.
Cellular Senescence
Permanent cell cycle arrest in response to stress or telomere shortening.
Cytokinesis
Physical division of the cytoplasm following nuclear division.
Toll-Like Receptor (TLR) Signaling
Pattern recognition receptors activating innate immune responses.
T Cell Receptor Signaling
Antigen-specific activation of T lymphocytes via TCR-MHC interaction.
Complement System
Cascade of plasma proteins enhancing pathogen clearance and inflammation.
Inflammasome Pathway
Intracellular sensor complexes activating inflammatory caspases and IL-1β/IL-18.
Type I Interferon Response
Antiviral defense system activating hundreds of interferon-stimulated genes.
B Cell Receptor Signaling
Antigen-specific activation of B lymphocytes for antibody production.
Antigen Processing & Presentation
MHC-mediated display of peptide antigens to T cells.
cGAS-STING Pathway
Cytosolic DNA sensing pathway activating innate immune defense.
Natural Killer Cell Activation
Innate lymphocyte killing of virus-infected and tumor cells via receptor balance.
T Helper Cell Differentiation
Polarization of naive CD4+ T cells into specialized effector subsets.
Intrinsic Apoptosis (Mitochondrial)
Cell death triggered by internal stress via mitochondrial cytochrome c release.
Extrinsic Apoptosis (Death Receptor)
Cell death initiated by death ligand-receptor interactions at the cell surface.
Autophagy
Self-digestion pathway recycling cellular components via lysosomal degradation.
Necroptosis
Regulated necrotic cell death mediated by RIPK1-RIPK3-MLKL signaling.
Ferroptosis
Iron-dependent regulated cell death driven by lipid peroxidation.
Pyroptosis
Inflammatory cell death mediated by gasdermin pore formation.
Receptor-Mediated Endocytosis
Clathrin-coated pit internalization of receptor-ligand complexes.
Vesicular Transport (Secretory Pathway)
ER-to-Golgi-to-plasma membrane trafficking via coated vesicles.
Ion Channel Signaling
Selective ion flux through membrane channels driving electrical and chemical signals.
ABC Transporter Superfamily
ATP-driven efflux pumps transporting diverse substrates across membranes.
Nuclear Import/Export
Ran-GTPase-driven transport of macromolecules through nuclear pore complexes.
Mitochondrial Protein Import
Targeting and translocation of nuclear-encoded proteins into mitochondria.
Hedgehog Signaling Pathway
Morphogen gradient pathway controlling tissue patterning and stem cell maintenance.
TGF-β/BMP Signaling
Multifunctional cytokine signaling controlling growth, differentiation, and immune regulation.
Retinoic Acid Signaling
Vitamin A-derived morphogen controlling anterior-posterior patterning.
FGF Signaling
Fibroblast growth factor signaling controlling proliferation, differentiation, and organogenesis.
Epithelial-Mesenchymal Transition (EMT)
Cellular program converting epithelial cells to motile mesenchymal phenotype.
Planar Cell Polarity (PCP)
Non-canonical Wnt pathway coordinating tissue-level cell orientation.
Stem Cell Pluripotency Network
Transcription factor network maintaining embryonic stem cell self-renewal.
Somitogenesis (Segmentation Clock)
Oscillating gene expression driving periodic formation of somites.
Synaptic Transmission
Chemical neurotransmission across synaptic clefts between neurons.
Dopamine Signaling
Dopaminergic neurotransmission regulating reward, motivation, and motor control.
Glutamate Signaling
Excitatory neurotransmission via ionotropic and metabotropic glutamate receptors.
Long-Term Potentiation / Depression (LTP/LTD)
Activity-dependent strengthening or weakening of synaptic connections.
Serotonin (5-HT) Signaling
Serotonergic neurotransmission modulating mood, sleep, appetite, and cognition.
GABAergic Signaling
Primary inhibitory neurotransmission in the central nervous system.
Neurotrophin Signaling
Growth factor signaling promoting neuronal survival, differentiation, and plasticity.
Circadian Clock Pathway
Transcription-translation feedback loops generating ~24-hour biological rhythms.
HPA Axis (Stress Response)
Hypothalamic-pituitary-adrenal axis regulating cortisol and stress response.
Thyroid Hormone Signaling
T3/T4 regulation of metabolism, growth, and development via nuclear receptors.
Estrogen Signaling
Estrogen receptor-mediated regulation of reproduction, bone, and cardiovascular health.
Androgen Signaling
Testosterone and DHT signaling via androgen receptor in male development and physiology.
Growth Hormone / IGF-1 Axis
GH-driven somatic growth and metabolism via hepatic IGF-1 production.
Vitamin D Signaling
Vitamin D3 activation and nuclear receptor signaling for calcium homeostasis.
Leptin Signaling
Adipocyte hormone signaling to the hypothalamus regulating energy balance.
Renin-Angiotensin-Aldosterone System (RAAS)
Hormonal cascade regulating blood pressure, fluid balance, and electrolytes.
Muscle Contraction (Excitation-Contraction Coupling)
Calcium-dependent actin-myosin sliding mechanism generating muscle force.
Actin Cytoskeleton Dynamics
Rho GTPase-regulated actin polymerization driving cell shape and motility.
Integrin Signaling & Focal Adhesions
Cell-ECM adhesion receptors transducing mechanical and chemical signals.
Cardiac Conduction System
Electrical conduction system coordinating rhythmic heart contraction.
De Novo Fatty Acid Synthesis
Cytoplasmic synthesis of palmitate from acetyl-CoA and malonyl-CoA.
Cholesterol Biosynthesis (Mevalonate Pathway)
Multi-step synthesis of cholesterol from acetyl-CoA via the mevalonate pathway.
Sphingolipid Metabolism
Biosynthesis and degradation of sphingolipids including ceramide signaling.
Bile Acid Synthesis
Hepatic conversion of cholesterol to bile acids for lipid digestion and signaling.
Eicosanoid Synthesis (Prostaglandins & Leukotrienes)
Arachidonic acid-derived lipid mediators regulating inflammation and vascular tone.
Lipoprotein Metabolism
Transport of lipids in blood via chylomicrons, VLDL, LDL, and HDL particles.