MARCH5 Gene

MARCH5 Gene

Overview

MARCH5 (Membrane Associated Ring-CH-Type Finger 5, also known as MARCHF5 or MITOL) encodes a mitochondrial outer membrane E3 ubiquitin ligase that plays critical roles in mitochondrial quality control, dynamics, and innate immune signaling. MARCH5 ubiquitinates misfolded proteins on the mitochondrial surface, regulates [mitochondrial fission](/mechanisms/mitochondrial-dynamics) by targeting [DRP1](/genes/dnm1l) and [MFN1/2](/genes/mfn2), and controls [MAVS](/genes/mavs)-dependent antiviral signaling. In the context of neurodegeneration, MARCH5 is essential for clearing aggregation-prone proteins that accumulate on mitochondria, and its dysfunction contributes to mitochondrial fragmentation and neuronal death in [Parkinson's disease](/diseases/parkinsons-disease) and [Alzheimer's disease](/diseases/alzheimers-disease).

MARCH5 Gene

Overview

MARCH5 (Membrane Associated Ring-CH-Type Finger 5, also known as MARCHF5 or MITOL) encodes a mitochondrial outer membrane E3 ubiquitin ligase that plays critical roles in mitochondrial quality control, dynamics, and innate immune signaling. MARCH5 ubiquitinates misfolded proteins on the mitochondrial surface, regulates [mitochondrial fission](/mechanisms/mitochondrial-dynamics) by targeting [DRP1](/genes/dnm1l) and [MFN1/2](/genes/mfn2), and controls [MAVS](/genes/mavs)-dependent antiviral signaling. In the context of neurodegeneration, MARCH5 is essential for clearing aggregation-prone proteins that accumulate on mitochondria, and its dysfunction contributes to mitochondrial fragmentation and neuronal death in [Parkinson's disease](/diseases/parkinsons-disease) and [Alzheimer's disease](/diseases/alzheimers-disease).

<div class="infobox infobox-gene"> [@karbowski2007]
<div class="infobox-header">MARCH5</div> [@yoo2015]
<table> [@sugiura2013]
<tr><td class="infobox-label">Full Name</td><td>Membrane Associated Ring-CH-Type Finger 5</td></tr> [@nagashima2014]
<tr><td class="infobox-label">Gene Symbol</td><td>MARCH5 (MARCHF5, MITOL)</td></tr> [@shiiba2021]
<tr><td class="infobox-label">Chromosomal Location</td><td>10q23.33</td></tr>
<tr><td class="infobox-label">NCBI Gene ID</td><td>[54708](https://www.ncbi.nlm.nih.gov/gene/54708)</td></tr>
<tr><td class="infobox-label">Ensembl ID</td><td>[ENSG00000148627](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000148627)</td></tr>
<tr><td class="infobox-label">UniProt ID</td><td>[Q9NX47](https://www.uniprot.org/uniprot/Q9NX47)</td></tr>
<tr><td class="infobox-label">Protein</td><td>[MARCH5 Protein](/proteins/march5-protein)</td></tr>
<tr><td class="infobox-label">Associated Diseases</td><td>[PD](/diseases/parkinsons-disease), [AD](/diseases/alzheimers-disease), [ALS](/diseases/amyotrophic-lateral-sclerosis)</td></tr>
</table>
</div>

Function

Mitochondrial Protein Quality Control

• Ubiquitinates misfolded or damaged OMM proteins, targeting them for proteasomal degradation (mitochondria-associated degradation, MAD)
• Substrates include mislocalized tail-anchored proteins, oxidatively damaged membrane proteins, and aggregation-prone substrates
• Works with the AAA-ATPase [VCP/p97](/genes/vcp) to extract ubiquitinated OMM proteins for proteasomal degradation

Mitochondrial Dynamics Regulation

• Fission: Ubiquitinates [DRP1](/genes/dnm1l) (Dynamin-related protein 1) to modulate its activity and turnover at mitochondrial fission sites
• Fusion: Ubiquitinates and regulates turnover of [MFN1](/genes/mfn1) and [MFN2](/genes/mfn2) (Mitofusins) on the OMM
• Net effect: MARCH5 loss causes excessive mitochondrial fragmentation due to uncontrolled [DRP1](/proteins/drp1-protein) accumulation and reduced fusogenic capacity

Innate Immune Regulation

• K48-linked ubiquitination of MAVS targets it for proteasomal degradation
• This prevents chronic type I interferon production from mitochondrial damage
• Relevant to neuroinflammation: MARCH5 deficiency prolongs MAVS-dependent IFN-β signaling, contributing to sterile inflammation

Clearance of Aggregation-Prone Proteins

• Expanded polyQ [huntingtin](/proteins/huntingtin-protein) fragments that associate with the OMM
• Mutant [SOD1](/proteins/sod1-protein) aggregates on mitochondria in ALS
• [α-Synuclein](/proteins/alpha-synuclein) fragments imported into mitochondria

Disease Associations

Parkinson's Disease

• MARCH5 cooperates with [PINK1](/genes/pink1)/[Parkin](/genes/prkn) in mitophagy: MARCH5 performs initial ubiquitination of OMM proteins on damaged mitochondria, while Parkin amplifies the ubiquitin signal
• MARCH5 loss impairs mitophagy initiation, leading to accumulation of dysfunctional mitochondria in dopaminergic [neurons](/entities/neurons)
• [α-Synuclein](/proteins/alpha-synuclein) overexpression reduces MARCH5 levels in neuronal cells, creating a feed-forward mitochondrial dysfunction loop
• MARCH5 ubiquitinates mutant [LRRK2](/genes/lrrk2) (G2019S) on mitochondria, promoting its clearance

Alzheimer's Disease

• [Amyloid-beta](/proteins/amyloid-beta) oligomers localize to mitochondrial membranes; MARCH5 helps clear Aβ-associated mitochondrial damage
• MARCH5 expression is reduced in AD hippocampal neurons, correlating with mitochondrial fragmentation
• MARCH5 deficiency exacerbates [tau](/proteins/tau)-induced mitochondrial dysfunction through DRP1 dysregulation
• MARCH5 overexpression rescues Aβ-induced mitochondrial morphology defects in neuronal cultures

ALS

• Mutant [SOD1](/entities/sod1) (G93A, A4V) misfolds and accumulates on the OMM; MARCH5 ubiquitinates misfolded SOD1 for proteasomal clearance
• MARCH5 depletion in motor neurons accelerates mutant SOD1 aggregation and cell death
• [TDP-43](/genes/tardbp) C-terminal fragments also accumulate on mitochondria and are MARCH5 substrates

Huntington's Disease

• Mutant [HTT](/genes/htt) polyQ fragments associate with mitochondria and impair function
• MARCH5 ubiquitinates mutant [HTT](/proteins/huntingtin) fragments on the OMM, promoting their degradation
• MARCH5 overexpression reduces mitochondria-associated polyQ aggregation in HD models

Expression

• Neurons: Moderate expression; essential for neuronal mitochondrial quality control
• Brain regions: Enriched in substantia nigra, [hippocampus](/brain-regions/hippocampus), and [cortex](/brain-regions/cortex) — regions with high mitochondrial metabolic demand
• Heart and muscle: High expression; critical for cardiac mitochondrial homeostasis
• [Microglia](/cell-types/microglia-neuroinflammation): Low-moderate expression

Therapeutic Targeting

• MARCH5 upregulation: Gene therapy or small molecule MARCH5 inducers could enhance mitochondrial protein quality control
• Substrate-specific approaches: Enhancing MARCH5 activity toward disease-specific substrates (mutant SOD1, α-synuclein, Aβ-associated damage)
• Combination with mitophagy enhancers: MARCH5 + PINK1/Parkin activation for synergistic mitochondrial clearance
• USP30 inhibition: The deubiquitinase [USP30](/genes/usp30) opposes MARCH5/Parkin-mediated ubiquitination; USP30 inhibitors enhance mitochondrial quality control

See Also

• [Mitochondrial Dysfunction](/mechanisms/mitochondrial-dysfunction)
• [PINK1](/genes/pink1) / [Parkin](/genes/prkn) — mitophagy pathway
• [DRP1](/genes/dnm1l) — mitochondrial fission
• [MFN2](/genes/mfn2) — mitochondrial fusion
• [VCP](/genes/vcp) — AAA-ATPase for OMM protein extraction

External Links

• [NCBI Gene: MARCHF5](https://www.ncbi.nlm.nih.gov/gene/54708)
• [UniProt: Q9NX47](https://www.uniprot.org/uniprot/Q9NX47)
• [GeneCards: MARCHF5](https://www.genecards.org/cgi-bin/carddisp.pl?gene=MARCHF5)
• [Allen Brain Atlas: MARCHF5](https://human.brain-map.org/microarray/search/show?search_term=MARCHF5)

References