Seroatlas · Human Serome Atlas

FIS1

Mitochondrial fission 1 protein

Also known as: CGI-135, FIS1_HUMAN, H_NH0132A01.6, TTC11

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q9Y3D6
Gene
FIS1
Ensembl
ENSG00000214253
Chromosome
7
Canonical length
152 aa
Protein class
Plasma proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Mitochondria

OverviewNCBI Gene

Enables identical protein binding activity; lipid binding activity; and molecular adaptor activity. Involved in several processes, including negative regulation of ATP metabolic process; negative regulation of fatty acid transport; and organelle fission. Acts upstream of or within mitochondrion organization. Located in mitochondrial outer membrane and peroxisomal membrane. Part of protein-containing complex. Biomarker of Alzheimer's disease. [provided by Alliance of Genome Resources, Apr 2025]

Canonical amino-acid sequenceUniProt

152 residues, UniProt reviewed canonical sequence.

>Q9Y3D6|FIS1
     1  MEAVLNELVS VEDLLKFEKK FQSEKAAGSV SKSTQFEYAW CLVRSKYNDD IRKGIVLLEE
    61  LLPKGSKEEQ RDYVFYLAVG NYRLKEYEKA LKYVRGLLQT EPQNNQAKEL ERLIDKAMKK
   121  DGLVGMAIVG GMALGVAGLA GLIGLAVSKS KS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FIS1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.39
Highest tissue expression
428 nTPM

Expression across tissuesHPA

Tissue

  • spinal cord: 428 nTPM
  • skeletal muscle: 370 nTPM
  • midbrain: 299 nTPM
  • heart muscle: 278 nTPM
  • tongue: 265 nTPM
  • amygdala: 227 nTPM

Single-cell type

  • late spermatids: 1,219 nCPM
  • thymic myoid cells: 734 nCPM
  • enterocytes: 559 nCPM
  • esophageal apical cells: 537 nCPM
  • esophageal suprabasal cells: 515 nCPM
  • parietal cells: 488 nCPM

Immune cell

  • total PBMC: 208 nTPM
  • T-reg: 156 nTPM
  • basophil: 154 nTPM
  • naive B-cell: 154 nTPM
  • memory B-cell: 153 nTPM
  • myeloid DC: 150 nTPM

Brain region

  • white matter: 208 nTPM
  • medulla oblongata: 181 nTPM
  • cerebellum: 171 nTPM
  • basal ganglia: 161 nTPM
  • spinal cord: 152 nTPM
  • pons: 148 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.55
gnomAD pLI
0
gnomAD missense Z
0.38
DepMap mean gene effect
-0.29
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Tetratricopeptide-like helical domain superfamily
  • Mitochondria fission 1 protein
  • Fis1, N-terminal tetratricopeptide repeat
  • Fis1, C-terminal tetratricopeptide repeat
  • Mitochondria fission protein Fis1, cytosolic domain
  • Fis1 N-terminal tetratricopeptide repeat
  • Fis1 C-terminal tetratricopeptide repeat

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of FIS1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FIS1 as an antibody target. Whether an autoantibody or antibody against FIS1 could matter depends on whether native FIS1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FIS1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label FIS1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FIS1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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