SLC40A1 Gene

Introduction

Slc40A1 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Solute Carrier Family 40 Member 1 (Ferroportin) ^1(2012)2012

Overview

flowchart TD
    SLC40A1["SLC40A1"] -->|"causes"| iron_overload["iron overload"]
    SLC40A1["SLC40A1"] -->|"therapeutic target"| Als["Als"]
    SLC40A1["SLC40A1"] -->|"therapeutic target"| Cancer["Cancer"]
    SLC40A1["SLC40A1"] -->|"activates"| Ferroptosis["Ferroptosis"]
    SLC40A1["SLC40A1"] -->|"expressed in"| Als["Als"]
    SLC40A1["SLC40A1"] -->|"associated with"| Cancer["Cancer"]
    SLC40A1["SLC40A1"] -->|"associated with"| ALS["ALS"]
    SLC40A1["SLC40A1"] -->|"therapeutic target"| C1QA["C1QA"]
    SLC40A1["SLC40A1"] -->|"expressed in"| ASC["ASC"]
    SLC40A1["SLC40A1"] -->|"expressed in"| NLRP3["NLRP3"]
    SLC40A1["SLC40A1"] -->|"expressed in"| JAK1["JAK1"]
    SLC40A1["SLC40A1"] -->|"expressed in"| PCBP1["PCBP1"]
    SLC40A1["SLC40A1"] -->|"expressed in"| NRF2["NRF2"]
    SLC40A1["SLC40A1"] -->|"expressed in"| STAT3["STAT3"]
    style SLC40A1 fill:#4fc3f7,stroke:#333,color:#000

SLC40A1 Gene is involved in biological pathways relevant to neurodegenerative diseases. It plays important roles in neuronal function, cellular signaling, or stress response mechanisms.

Dysregulation or mutations in this gene/protein contribute to the pathogenesis of Alzheimer’s disease, Parkinson’s disease, and related neurodegenerative disorders.

Function

SLC40A1 encodes ferroportin, the only known iron exporter in mammals. This protein is essential for iron homeostasis and is expressed in cells that export iron, including macrophages, hepatocytes, and enterocytes.

Key functions include:

• Iron export: Ferroportin exports iron from cells into the plasma

• Systemic iron regulation: Controls iron entry into circulation from gut, liver, and spleen

• Ferroptosis regulation: Involved in iron-dependent cell death pathways

• Hepcidin receptor: Ferroportin is the target of hepcidin, the iron regulatory hormone

• Cellular iron homeostasis: Prevents iron accumulation in macrophages and other cells

Ferroportin is a multipass transmembrane protein with 12 transmembrane domains. It exports Fe2+ iron, which is then oxidized to Fe3+ by hephaestin for transferrin binding.

Disease Associations

Neurodegeneration with Brain Iron Accumulation (NBIA) Type IV

SLC40A1 mutations cause a form of NBIA:

• Iron overload: Mutations lead to iron accumulation in the brain, particularly in the globus pallidus

• Motor symptoms: Patients present with progressive dystonia, parkinsonism, and gait disturbance

• Cognitive decline: Some patients develop cognitive impairment

• MRI findings: T2 hypointensity in basal ganglia indicating iron deposition

Mutations can be gain-of-function (leading to iron retention) or loss-of-function (causing iron overload syndrome similar to hemochromatosis).

Ferroportin Disease

Heterozygous SLC40A1 mutations cause ferroportin disease:

• Iron retention: Macrophages retain iron (ferroportin-high phenotype)

• Elevated ferritin: High serum ferritin with normal transferrin saturation

• Liver involvement: Iron deposition in liver hepatocytes

• Atypical presentation: Differs from classic hemochromatosis

Alzheimer’s Disease

Ferroportin dysfunction may contribute to AD:

• Brain iron dysregulation: Iron accumulation in AD brain regions

• Ferroptosis: Iron-dependent cell death may contribute to neuronal loss

• Amyloid interaction: Iron can catalyze Aβ aggregation

• Oxidative stress: Iron promotes ROS generation

Parkinson’s Disease

Iron metabolism is altered in PD:

• Substantia nigra iron: Elevated iron in PD substantia nigra

• Ferroportin expression: Altered ferroportin in PD brain

• Dopaminergic neurons: Iron may promote dopaminergic neuron loss

Expression

SLC40A1 shows cell-type specific expression ^{4Ferroportin in neurons2019 · J Neurosci Res · PMID 30549387Open reference}:

• Macrophages: High expression in splenic, hepatic, and bone marrow macrophages

• Enterocytes: Expression in duodenal enterocytes for dietary iron absorption

• Hepatocytes: Expresses ferroportin for iron release into circulation

• Neurons: Low basal expression in neurons

• Microglia: Expressed in brain microglia

Expression is regulated by iron levels and hepcidin (which causes ferroportin internalization and degradation).

Iron Export Mechanism: Detailed Molecular Analysis

Ferroportin Structure and Function

Ferroportin is a unique iron exporter with distinct structural features ^{5Ferroportin and iron export2015 · Nat Rev Gastroenterol Hepatol · PMID 25645969Open reference}:

1. Protein architecture:

   • 12 transmembrane domains

   • Multiple iron-binding sites

   • Basolateral (systemic) localization in polarized cells

2. Iron export process:

   • Exports Fe²⁺ (ferrous iron)

   • Oxidation to Fe³⁺ by hephaestin (intestinal) or ceruloplasmin (other tissues)

   • Transferrin binding for systemic transport

   • Rate-limiting step in iron export

3. Regulation by hepcidin ^{6Hepcidin and ferroportin in iron homeostasis2013 · Hematology Am Soc Hematol Educ Program · PMID 24319170Open reference}:

   • Hepcidin binds to ferroportin extracellular loop

   • Induces ferroportin internalization and degradation

   • Reduces iron export when body iron is high

   • Loss of function when hepcidin is elevated

Cellular Iron Homeostasis

Ferroportin is central to cellular iron balance:

Brain Iron Metabolism

Iron in the Central Nervous System

The brain has specialized iron handling mechanisms ^{7Iron metabolism in the brain2012 · Neurobiology of Aging · PMID 21908240Open reference 8Brain iron homeostasis and neurodegenerative disease2019 · J Neural Transm · PMID 30604123Open reference}:

1. Blood-brain barrier iron transport:

   • Transferrin receptor-mediated endocytosis

   • DMT1 (divalent metal transporter 1) for Fe²⁺ entry

   • Limited ferroportin expression at BBB

2. Neuronal iron import:

   • Transferrin-bound iron uptake via TfR1/TfR2

   • DMT1 for intracellular iron release

   • Limited export capacity in neurons

3. Glial iron handling:

   • Oligodendrocytes: High iron storage capacity

   • Astrocytes: Iron buffer function

   • Microglia: Iron handling in inflammation

Ferroportin in the Brain

Brain-specific ferroportin expression ^{4Ferroportin in neurons2019 · J Neurosci Res · PMID 30549387Open reference 9Ferroportin and neuroinflammation2019 · J Neuroinflammation · PMID 31269958Open reference}:

• Neurons: Low baseline expression, upregulates under iron overload

• Astrocytes: Moderate expression, role in iron buffering

• Microglia: Inducible expression during inflammation

• Endothelial cells: Limited BBB expression

• Oligodendrocytes: Important for myelin iron supply

Disease Mechanisms in Detail

Neurodegeneration with Brain Iron Accumulation (NBIA) Type IV

SLC40A1 mutations cause a distinctive form of NBIA ^2(2019)20190 ^2(2019)20191:

Pathogenesis:

• Gain-of-function mutations: Lead to iron retention (ferroportin resistance to hepcidin)

• Loss-of-function mutations: Cause iron overload syndrome similar to hemochromatosis

• Both mechanisms lead to brain iron accumulation

Clinical Presentation:

• Onset: Typically childhood or early adulthood

• Motor symptoms: Progressive dystonia, parkinsonism, gait disturbance

• Cognitive decline: Variable, from mild impairment to dementia

• MRI findings: T2 hypointensity in globus pallidus, “eye-of-the-tiger” sign

Genotype-phenotype correlations:

Ferroportin Disease

Hereditary ferroportin disease caused by SLC40A1 mutations ^2(2019)20192:

Type A (loss-of-function):

• Macrophage iron retention

• High ferritin, normal transferrin saturation

• Aceruloplasminemia-like phenotype

Type B (gain-of-function):

• Hepcidin-resistant ferroportin

• Elevated transferrin saturation

• Classic hemochromatosis phenotype

Alzheimer’s Disease

Ferroportin dysfunction contributes to AD pathogenesis ^2(2019)20193:

1. Brain iron dysregulation:

   • Iron accumulation in AD brain regions (frontal cortex, hippocampus)

   • Elevated ferritin in cerebrospinal fluid

   • Altered iron regulatory proteins

2. Ferroptosis mechanism:

   • Iron-dependent cell death pathway

   • Lipid peroxidation in neurons

   • GPX4 downregulation in AD brain

3. Amyloid interaction:

   • Iron catalyzes Aβ aggregation

   • Aβ co-localizes with iron in plaques

   • Iron promotes oxidative stress

4. Therapeutic implications:

   • Iron chelation approaches under investigation

   • Ferroportin modulators as potential treatment

   • Antioxidant strategies targeting iron

Parkinson’s Disease

Iron metabolism alterations in PD ^2(2019)20194:

1. Substantia nigra iron:

   • Markedly elevated iron in PD substantia nigra

   • Especially in dopaminergic neurons

   • Correlation with disease severity

2. Ferroportin expression:

   • Reduced ferroportin in PD brain

   • Altered hepcidin/ferroportin axis

   • Dysregulated iron export

3. Dopaminergic neuron vulnerability:

   • Iron promotes dopaminergic neuron loss

   • Oxidative stress contribution

   • Mitochondrial dysfunction

4. Therapeutic targets:

   • Iron chelation (deferoxamine, deferasirox)

   • Ferroportin activators

   • Antioxidant approaches

Neuroinflammation and Ferroportin

Ferroportin plays a role in neuroimmune interactions ^2(2019)20195:

1. Microglial iron handling:

   • Activated microglia accumulate iron

   • Ferroportin upregulation in inflammation

   • Altered iron release affects neurons

2. Inflammatory signaling:

   • IL-6 modulates ferroportin expression

   • LPS reduces ferroportin in macrophages

   • TNF-α affects neuronal iron homeostasis

3. Iron and neuroinflammation:

   • Iron promotes microglial activation

   • Reactive oxygen species generation

   • Cycle of inflammation and iron dysregulation

Therapeutic Approaches

Targeting Ferroportin

Multiple therapeutic strategies are being developed:

Iron Chelation Therapy

Current chelation approaches for NBIA and related disorders:

• Deferoxamine: Subcutaneous administration, limited CNS penetration

• Deferasirox: Oral, moderate CNS penetration

• Deferiprone: Can cross BBB, being investigated for neurodegeneration

• Novel chelators: Brain-penetrant compounds in development

Gene Therapy Considerations

• Viral vectors: AAV for CNS delivery

• Target cells: Neurons, astrocytes, microglia

• Challenges: Appropriate expression levels, regulation

Cross-Linking

• Alzheimer’s Disease — AD overview

• Parkinson’s Disease — PD overview

• Neurodegeneration with Brain Iron Accumulation (NBIA) — NBIA disorders

• Iron Metabolism — Experimental systems

• Ferroptosis — Iron-dependent cell death

• TF Gene — Transferrin

• FTH1 Gene — Ferritin heavy chain

• FTL Gene — Ferritin light chain

• Heph Gene — Hephaestin

• CP Gene — Ceruloplasmin

Background

The study of Slc40A1 Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.

Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.

See Also

• Alzheimer’s Disease

• Parkinson’s Disease

• Neurodegeneration with Brain Iron Accumulation (NBIA)

• Iron Metabolism Ferroptosis

• TF Gene

• FTH1 Gene

External Links

• NCBI Gene: SLC40A1

• UniProt: Q9NP59

• OMIM: 604653

• Ensembl: ENSG00000138448

Last updated: 2026-03-05