This is a mechanism module, not a specific disease. It is a pathological structure-formation ("Xogenesis") module. Xogenesis anchor: the terminal output is an amyloid deposit, an OGMS:0000079 portion of pathological body substance produced by an OGMS:0000081 pathological derivation (a new extracellular fibrillar deposit); process genus OGMS:0000061 pathological bodily process. Amyloid deposits are extracellular and systemic/multi-organ, so no single UBERON site is bound. MPATH has no "amyloid" class, a noted OBO gap; SNOMED "Morphologically abnormal structure" (49755003) is used only as an external census/gap guide and is not bound here. Disorder entries reference individual nodes via conforms_to (for example, "amyloidogenesis#Amyloid Fibril Formation and Extracellular Deposition"). The module defines the expected pathophysiology structure; conforming nodes in disorder files should include the corresponding cell types, biological processes, and causal edges, specialized to their disease context. Key disease-specific substitutions: AL amyloidosis substitutes a clonal immunoglobulin light chain; ATTR substitutes wild-type or variant transthyretin; AA substitutes serum amyloid A driven by chronic inflammation; Alzheimer disease substitutes amyloid-beta. Modules bind GO and CL terms only and do not use chemical (CHEBI) or disease (MONDO) term bindings, except in the treatments block where the therapeutic agent carries an ontology identifier per the treatment schema.
Amyloidogenic Precursor Protein
trigger
The proximal trigger of amyloidogenesis is an amyloidogenic precursor protein whose native fold is destabilized - by a point mutation, by overproduction, by aging, or by proteolytic processing - so that it is prone to misfold. The identity of the precursor defines the amyloidosis type (transthyretin, immunoglobulin light chain, serum amyloid A, amyloid-beta), but the shared feature is a metastable precursor poised to depart its native conformation.
Used by disorders
Amyloidosis
as Clonal Immunoglobulin Light-Chain Precursor Excess
Amyloidosis
as Sustained Serum Amyloid A Precursor Production
Amyloidosis
as TTR Tetramer Destabilization and Monomer Release
Downstream
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Protein Misfolding and Beta-Sheet Oligomerization
Show evidence (2 references)
"deposition of misfolded transthyretin (TTR) protein in the myocardial interstitium"
Identifies a destabilized precursor protein (transthyretin) whose misfolding underlies amyloid deposition, the trigger of this module. Evidence source is OTHER because this is a review.
"The major forms are transthyretin (ATTR) CA and light-chain (AL) CA, based on the respective precursor protein."
Establishes that the amyloidosis type is defined by its precursor protein (transthyretin or immunoglobulin light chain), the substituted trigger of this module. Evidence source is OTHER because this is a review.
Protein Misfolding and Beta-Sheet Oligomerization
amplifier
The destabilized precursor undergoes a conformational change from its native fold into beta-sheet-rich, aggregation-prone species. These misfolded monomers self-associate into soluble oligomers that both seed further aggregation (nucleation) and are themselves proteotoxic. This misfolding and oligomerization is the amplifying step that commits the precursor to the amyloid pathway.
Downstream
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Amyloid Fibril Formation and Extracellular Deposition
Show evidence (1 reference)
"Such protein aggregation may be brought about by conformational changes"
Attributes amyloid protein aggregation to conformational (misfolding) changes, the amplifier step that commits the precursor to aggregation. Evidence source is OTHER because this is a review.
Progressive Tissue Amyloid Accumulation
effector
Continued fibril deposition accumulates as amyloid within the extracellular matrix of affected organs, progressively expanding the interstitium and physically disrupting normal tissue architecture. This accumulation - the growing amyloid burden - is the effector step that converts molecular fibril formation into an organ-level structural lesion.
Show evidence (2 references)
"Cardiac amyloidosis (CA) is caused by the misfolding, accumulation and aggregation of proteins into large fibrils in the extracellular compartment of the myocardium, leading to restrictive cardiomyopathy, heart failure and death."
Documents progressive amyloid fibril accumulation in the extracellular compartment of the myocardium, the tissue-accumulation effector of this module. Evidence source is OTHER because this is a review.
"We show that the CIP is enriched with proteins that modify Aβ toxicity in vivo, suggesting the possibility of a vicious feedforward cycle in the context of AD."
Evidence that accumulating amyloid is not only a passive deposit: the amyloid-driven core insoluble proteome is itself enriched for modifiers of amyloid toxicity, implying a self-reinforcing loop in which deposition destabilizes the wider proteome and the destabilized proteome aggravates amyloid toxicity. Links this module to loss_of_proteostasis, where the same study supports the aggregation node. The feedforward cycle is proposed by the authors as a possibility, not demonstrated, and the evidence is from an amyloid-beta model rather than the AL/ATTR/AA precursors this module otherwise covers. Evidence source is MODEL_ORGANISM (transgenic C. elegans).
Organ Dysfunction
consequence
The clinical end state of the module. Amyloid infiltration and proteotoxic soluble oligomers impair the function of the affected organs - producing restrictive cardiomyopathy and heart failure (cardiac amyloidosis), peripheral and autonomic neuropathy, nephrotic-range proteinuria and renal failure, or neurodegeneration - the consequence of the conserved amyloidogenesis chain.
Show evidence (2 references)
"leading to restrictive cardiomyopathy, heart failure and death."
Establishes restrictive cardiomyopathy and heart failure as the organ dysfunction resulting from amyloid deposition, the consequence of this module. Evidence source is OTHER because this is a review.
"Their formation, deposition in tissues and consequent organ dysfunction is the central event in amyloidogenic diseases."
Names consequent organ dysfunction as the outcome of amyloid formation and tissue deposition, the consequence node of this module. Evidence source is OTHER because this is a review.