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Aliases for SPG21 Gene

Aliases for SPG21 Gene

  • Spastic Paraplegia 21 (Autosomal Recessive, Mast Syndrome) 2 3
  • ACP33 3 4 6
  • Acid Cluster Protein 33 3 4
  • Maspardin 2 3
  • Spastic Paraplegia 21 Autosomal Recessive Mast Syndrome Protein 4
  • Spastic Paraplegia 21 Protein 4
  • BM-019 3
  • GL010 3
  • MAST, 6
  • Mast 3

External Ids for SPG21 Gene

Previous GeneCards Identifiers for SPG21 Gene

  • GC13U900001
  • GC15M062972
  • GC15M063042
  • GC15M065255
  • GC15M042080

Summaries for SPG21 Gene

Entrez Gene Summary for SPG21 Gene

  • The protein encoded by this gene binds to the hydrophobic C-terminal amino acids of CD4 which are involved in repression of T cell activation. The interaction with CD4 is mediated by the noncatalytic alpha/beta hydrolase fold domain of this protein. It is thus proposed that this gene product modulates the stimulatory activity of CD4. Mutations in this gene are associated with autosomal recessive spastic paraplegia 21 (SPG21), also known as mast syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2014]

GeneCards Summary for SPG21 Gene

SPG21 (Spastic Paraplegia 21 (Autosomal Recessive, Mast Syndrome)) is a Protein Coding gene. Diseases associated with SPG21 include mast syndrome and spastic paraplegia 12. GO annotations related to this gene include CD4 receptor binding.

UniProtKB/Swiss-Prot for SPG21 Gene

  • May play a role as a negative regulatory factor in CD4-dependent T-cell activation.

Gene Wiki entry for SPG21 Gene

No data available for Tocris Summary , PharmGKB "VIP" Summary , fRNAdb sequence ontologies and piRNA Summary for SPG21 Gene

Genomics for SPG21 Gene

Regulatory Elements for SPG21 Gene

Genomic Location for SPG21 Gene

64,963,021 bp from pter
64,990,310 bp from pter
27,290 bases
Minus strand

Genomic View for SPG21 Gene

UCSC Golden Path with GeneCards custom track
Cytogenetic band:
Genomic Location for SPG21 Gene
GeneLoc Logo Genomic Neighborhood Exon StructureGene Density

RefSeq DNA sequence for SPG21 Gene

Proteins for SPG21 Gene

  • Protein details for SPG21 Gene (UniProtKB/Swiss-Prot)

    Protein Symbol:
    Recommended name:
    Protein Accession:
    Secondary Accessions:
    • B4DW44
    • Q6ZMB6

    Protein attributes for SPG21 Gene

    308 amino acids
    Molecular mass:
    34960 Da
    Quaternary structure:
    • Interacts with CD4. Interacts with ALDH16A1.

    Alternative splice isoforms for SPG21 Gene


neXtProt entry for SPG21 Gene

Proteomics data for SPG21 Gene at MOPED

Post-translational modifications for SPG21 Gene

  • Modification sites at PhosphoSitePlus
  • Modification sites at neXtProt

Antibody Products

No data available for DME Specific Peptides for SPG21 Gene

Domains for SPG21 Gene

Protein Domains for SPG21 Gene

Suggested Antigen Peptide Sequences for SPG21 Gene

GenScript: Design optimal peptide antigens:

Graphical View of Domain Structure for InterPro Entry



  • Belongs to the AB hydrolase superfamily.
  • Belongs to the AB hydrolase superfamily.
genes like me logo Genes that share domains with SPG21: view

No data available for Gene Families for SPG21 Gene

Function for SPG21 Gene

Molecular function for SPG21 Gene

UniProtKB/Swiss-Prot Function:
May play a role as a negative regulatory factor in CD4-dependent T-cell activation.

Gene Ontology (GO) - Molecular Function for SPG21 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005515 protein binding IPI 16189514
GO:0042609 CD4 receptor binding IPI 11113139
genes like me logo Genes that share ontologies with SPG21: view

miRNA Products

Inhibitory RNA Products

  • Predesigned siRNA for gene silencing in human,mouse,rat for SPG21

In Situ Assay Products

Flow Cytometry Products

No data available for Enzyme Numbers (IUBMB) , Phenotypes , Animal Models , miRNA , Transcription Factor Targets and HOMER Transcription for SPG21 Gene

Localization for SPG21 Gene

Subcellular locations from UniProtKB/Swiss-Prot for SPG21 Gene

Cytoplasm, cytosol. Membrane; Peripheral membrane protein. Endosome membrane; Peripheral membrane protein. Golgi apparatus, trans-Golgi network membrane; Peripheral membrane protein. Note=Partially localized in the cytosol but also accumulated on an intracellular vesicular compartment. Colocalizes with CD4 on endosomal/trans-Golgi network.

Subcellular locations from

Jensen Localization Image for SPG21 Gene COMPARTMENTS Subcellular localization image for SPG21 gene
Compartment Confidence
cytosol 5
endosome 5
golgi apparatus 5
nucleus 4
mitochondrion 1

Gene Ontology (GO) - Cellular Components for SPG21 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005634 nucleus IDA --
GO:0005654 nucleoplasm IDA --
GO:0005737 cytoplasm IDA --
GO:0005768 endosome --
GO:0005829 cytosol IDA 11113139
genes like me logo Genes that share ontologies with SPG21: view

Pathways for SPG21 Gene

SuperPathways for SPG21 Gene

No Data Available

Gene Ontology (GO) - Biological Process for SPG21 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0008219 cell death --
GO:0050851 antigen receptor-mediated signaling pathway IC 11113139
genes like me logo Genes that share ontologies with SPG21: view

No data available for Pathways by source for SPG21 Gene

Transcripts for SPG21 Gene

Unigene Clusters for SPG21 Gene

Spastic paraplegia 21 (autosomal recessive, Mast syndrome):
Representative Sequences:

miRNA Products

Inhibitory RNA Products

  • Predesigned siRNA for gene silencing in human,mouse,rat for SPG21

Flow Cytometry Products

Alternative Splicing Database (ASD) splice patterns (SP) for SPG21 Gene

ExUns: 1a · 1b ^ 2a · 2b ^ 3a · 3b ^ 4 ^ 5 ^ 6 ^ 7a · 7b · 7c ^ 8 ^ 9a · 9b ^ 10 ^ 11 ^ 12 ^ 13
SP1: - - - - - - -
SP2: - - - - -
SP3: - - -
SP5: - - - - - - - -
SP6: - - - - -

Relevant External Links for SPG21 Gene

GeneLoc Exon Structure for
ECgene alternative splicing isoforms for

Expression for SPG21 Gene

mRNA expression in normal human tissues for SPG21 Gene

mRNA expression in embryonic tissues and stem cells from LifeMap Discovery

Protein differential expression in normal tissues for SPG21 Gene

This gene is overexpressed in Bone (18.3), Monocytes (7.5), and Peripheral blood mononuclear cells (6.7).

Integrated Proteomics: protein expression from ProteomicsDB, PaxDb, MOPED, and MaxQB for SPG21 Gene

SOURCE GeneReport for Unigene cluster for SPG21 Gene Hs.242458

mRNA Expression by UniProt/SwissProt for SPG21 Gene

Tissue specificity: Expressed in all tissues tested, including heart, brain, placenta, lung, liver, skeletal muscle, kidney and pancreas. Expressed in J.CaM1.6, HuT 78 and HeLa cell lines (at protein level).
genes like me logo Genes that share expressions with SPG21: view

Expression partners for SPG21 Gene

* - Elite partner

Primer Products

In Situ Assay Products

No data available for mRNA differential expression in normal tissues for SPG21 Gene

Orthologs for SPG21 Gene

This gene was present in the common ancestor of eukaryotes.

Orthologs for SPG21 Gene

Organism Taxonomy Gene Similarity Type Details
(Bos Taurus)
Mammalia SPG21 35
  • 93.4 (n)
  • 98.7 (a)
SPG21 36
  • 99 (a)
(Canis familiaris)
Mammalia SPG21 35
  • 92.64 (n)
  • 98.7 (a)
SPG21 36
  • 99 (a)
(Mus musculus)
Mammalia Spg21 35
  • 88.06 (n)
  • 98.05 (a)
Spg21 16
Spg21 36
  • 98 (a)
(Pan troglodytes)
Mammalia SPG21 35
  • 99.78 (n)
  • 100 (a)
SPG21 36
  • 100 (a)
(Rattus norvegicus)
Mammalia Spg21 35
  • 89.36 (n)
  • 96.92 (a)
(Monodelphis domestica)
Mammalia SPG21 36
  • 97 (a)
(Ornithorhynchus anatinus)
Mammalia SPG21 36
  • 96 (a)
(Gallus gallus)
Aves SPG21 35
  • 82.36 (n)
  • 94.81 (a)
SPG21 36
  • 93 (a)
(Anolis carolinensis)
Reptilia SPG21 36
  • 90 (a)
tropical clawed frog
(Silurana tropicalis)
Amphibia spg21 35
  • 77.92 (n)
  • 89.61 (a)
Str.18797 35
(Danio rerio)
Actinopterygii Dr.27161 35
spg21 35
  • 75.65 (n)
  • 87.66 (a)
spg21 36
  • 87 (a)
SPG21 (2 of 2) 36
  • 87 (a)
rainbow trout
(Oncorhynchus mykiss)
Actinopterygii Omy.627 35
thale cress
(Arabidopsis thaliana)
eudicotyledons AT4G12230 35
  • 53.38 (n)
  • 45.86 (a)
(Oryza sativa)
Liliopsida Os10g0169800 35
  • 51.81 (n)
  • 44.96 (a)
sea squirt
(Ciona savignyi)
Ascidiacea -- 36
  • 45 (a)
Species with no ortholog for SPG21:
  • A. gosspyii yeast (Ashbya gossypii)
  • Actinobacteria (Mycobacterium tuberculosis)
  • African clawed frog (Xenopus laevis)
  • African malaria mosquito (Anopheles gambiae)
  • Alicante grape (Vitis vinifera)
  • alpha proteobacteria (Wolbachia pipientis)
  • amoeba (Dictyostelium discoideum)
  • Archea (Pyrococcus horikoshii)
  • baker's yeast (Saccharomyces cerevisiae)
  • barley (Hordeum vulgare)
  • beta proteobacteria (Neisseria meningitidis)
  • bread mold (Neurospora crassa)
  • Chromalveolata (Phytophthora infestans)
  • common water flea (Daphnia pulex)
  • corn (Zea mays)
  • E. coli (Escherichia coli)
  • filamentous fungi (Aspergillus nidulans)
  • Firmicute bacteria (Streptococcus pneumoniae)
  • fission yeast (Schizosaccharomyces pombe)
  • fruit fly (Drosophila melanogaster)
  • green algae (Chlamydomonas reinhardtii)
  • honey bee (Apis mellifera)
  • K. lactis yeast (Kluyveromyces lactis)
  • loblloly pine (Pinus taeda)
  • malaria parasite (Plasmodium falciparum)
  • medicago trunc (Medicago Truncatula)
  • moss (Physcomitrella patens)
  • orangutan (Pongo pygmaeus)
  • pig (Sus scrofa)
  • rice blast fungus (Magnaporthe grisea)
  • schistosome parasite (Schistosoma mansoni)
  • sea anemone (Nematostella vectensis)
  • sea urchin (Strongylocentrotus purpuratus)
  • sorghum (Sorghum bicolor)
  • soybean (Glycine max)
  • stem rust fungus (Puccinia graminis)
  • sugarcane (Saccharum officinarum)
  • tomato (Lycopersicon esculentum)
  • toxoplasmosis (Toxoplasma gondii)
  • Trichoplax (Trichoplax adhaerens)
  • wheat (Triticum aestivum)
  • worm (Caenorhabditis elegans)

Evolution for SPG21 Gene

Gene Tree for SPG21 (if available)
Gene Tree for SPG21 (if available)

Paralogs for SPG21 Gene

No data available for Paralogs for SPG21 Gene

Variants for SPG21 Gene

Sequence variations from dbSNP and Humsavar for SPG21 Gene

SNP ID Clin Chr 15 pos Sequence Context AA Info Type MAF
rs7322 -- 64,963,363(-) GTGCA(A/G)ATTTT utr-variant-3-prime
rs2177241 -- 64,969,594(-) CTGTA(A/G)AAGGC intron-variant
rs2280555 -- 64,969,692(-) AAAAA(A/C)AAAAA intron-variant
rs4128936 -- 64,985,367(-) TCGTT(C/T)AATCA intron-variant
rs4238398 -- 64,982,611(+) ACACT(C/T)CTGCA intron-variant

Structural Variations from Database of Genomic Variants (DGV) for SPG21 Gene

Variant ID Type Subtype PubMed ID
nsv833041 CNV Loss 17160897
nsv510404 CNV Loss 20534489

Relevant External Links for SPG21 Gene

HapMap Linkage Disequilibrium report
Human Gene Mutation Database (HGMD)

No data available for Polymorphic Variants from UniProtKB/Swiss-Prot for SPG21 Gene

Disorders for SPG21 Gene

MalaCards: The human disease database

MalaCards: The human disease database.

Search for SPG21 Gene in MalaCards »

(3) Diseases for SPG21 Gene

(1) OMIM Diseases for SPG21 Gene (608181)


  • Spastic paraplegia 21, autosomal recessive (SPG21) [MIM:248900]: A form of spastic paraplegia, a neurodegenerative disorder characterized by a slow, gradual, progressive weakness and spasticity of the lower limbs. Rate of progression and the severity of symptoms are quite variable. Initial symptoms may include difficulty with balance, weakness and stiffness in the legs, muscle spasms, and dragging the toes when walking. In some forms of the disorder, bladder symptoms (such as incontinence) may appear, or the weakness and stiffness may spread to other parts of the body. SPG21 is associated with dementia and other central nervous system abnormalities. Subtle childhood abnormalities may be present, but the main features develop in early adulthood. The disease is slowly progressive, and cerebellar and extrapyramidal signs are also found in patients with advanced disease. Patients have a thin corpus callosum and white-matter abnormalities. {ECO:0000269 PubMed:14564668}. Note=The disease is caused by mutations affecting the gene represented in this entry.

(1) University of Copenhagen DISEASES for SPG21 Gene

genes like me logo Genes that share disorders with SPG21: view

No data available for Novoseek inferred disease relationships , Genatlas and External Links for SPG21 Gene

Publications for SPG21 Gene

  1. Maspardin is mutated in Mast syndrome, a complicated form of hereditary spastic paraplegia associated with dementia. (PMID: 14564668) Simpson M.A. … Crosby A.H. (Am. J. Hum. Genet. 2003) 2 3 4 23
  2. Cloning of ACP33 as a novel intracellular ligand of CD4. (PMID: 11113139) Zeitlmann L. … Kolanus W. (J. Biol. Chem. 2001) 2 3 4 23
  3. Interaction of the SPG21 protein ACP33/maspardin with the aldehyde dehydrogenase ALDH16A1. (PMID: 19184135) Hanna M.C. … Blackstone C. (Neurogenetics 2009) 3 4 23
  4. Complete sequencing and characterization of 21,243 full-length human cDNAs. (PMID: 14702039) Ota T. … Sugano S. (Nat. Genet. 2004) 3 4
  5. The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). (PMID: 15489334) Gerhard D.S. … Malek J. (Genome Res. 2004) 3 4

Products for SPG21 Gene

Sources for SPG21 Gene

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