Human Gene SPG21 (uc002aoe.3) Description and Page Index
  Description: Homo sapiens spastic paraplegia 21 (autosomal recessive, Mast syndrome) (SPG21), transcript variant 1, mRNA.
RefSeq Summary (NM_016630): 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].
Transcript (Including UTRs)
   Position: hg19 chr15:65,255,363-65,282,251 Size: 26,889 Total Exon Count: 9 Strand: -
Coding Region
   Position: hg19 chr15:65,255,961-65,275,907 Size: 19,947 Coding Exon Count: 8 

Page IndexSequence and LinksUniProtKB CommentsMalaCardsCTDGene Alleles
RNA-Seq ExpressionMicroarray ExpressionRNA StructureProtein StructureOther SpeciesGO Annotations
mRNA DescriptionsOther NamesGeneReviewsModel InformationMethods
Data last updated: 2013-06-14

-  Sequence and Links to Tools and Databases
Genomic Sequence (chr15:65,255,363-65,282,251)mRNA (may differ from genome)Protein (308 aa)
Gene SorterGenome BrowserOther Species FASTAVisiGeneGene interactionsTable Schema
BioGPSCGAPEnsemblEntrez GeneExonPrimerGeneCards
neXtProtOMIMPubMedStanford SOURCETreefamUniProtKB

-  Comments and Description Text from UniProtKB
DESCRIPTION: RecName: Full=Maspardin; AltName: Full=Acid cluster protein 33; AltName: Full=Spastic paraplegia 21 autosomal recessive Mast syndrome protein; AltName: Full=Spastic paraplegia 21 protein;
FUNCTION: May play a role as a negative regulatory factor in CD4- dependent T-cell activation.
SUBUNIT: Interacts with CD4. Interacts with ALDH16A1.
SUBCELLULAR LOCATION: 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.
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).
DISEASE: Defects in SPG21 are the cause of spastic paraplegia autosomal recessive type 21 (SPG21) [MIM:248900]; also known as Mast syndrome. Spastic paraplegia is 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.
SIMILARITY: Belongs to the AB hydrolase superfamily.

-  MalaCards Disease Associations
  MalaCards Gene Search: SPG21
Diseases sorted by gene-association score: mast syndrome* (1408), melanoma and neural system tumor syndrome* (283), paraplegia (20), spastic paraplegia 11, autosomal recessive (13), spastic paraplegia 24, autosomal recessive (12), spastic paraplegia 32, autosomal recessive (12), spastic paraplegia 48, autosomal recessive (12), spastic paraplegia 15, autosomal recessive (10), spastic paraplegia 18, autosomal recessive (10), spastic paraplegia 30, autosomal recessive (10), spastic paraplegia 46, autosomal recessive (10), spastic paraplegia 35, autosomal recessive (9), charcot-marie-tooth disease, type 2r (8), charcot-marie-tooth disease, recessive intermediate d (8), spastic paraplegia 44, autosomal recessive (8), charcot-marie-tooth disease, axonal, type 2t (7), spastic paraplegia 55, autosomal recessive (7), charcot-marie-tooth disease type 2a2 (7), charcot-marie-tooth disease, axonal, type 2p (7), charcot-marie-tooth disease, axonal, type 2h (7), amyotrophic lateral sclerosis type 5 (6), charcot-marie-tooth disease, axonal, type 2s (4), hereditary spastic paraplegia (3)
* = Manually curated disease association

-  Comparative Toxicogenomics Database (CTD)
  The following chemicals interact with this gene           more ... click here to view the complete list

+  Common Gene Haplotype Alleles
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-  RNA-Seq Expression Data from GTEx (53 Tissues, 570 Donors)
  Highest median expression: 27.78 RPKM in Cervix - Endocervix
Total median expression: 903.51 RPKM

View in GTEx track of Genome Browser    View at GTEx portal     View GTEx Body Map

+  Microarray Expression Data
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-  mRNA Secondary Structure of 3' and 5' UTRs
RegionFold EnergyBasesEnergy/Base
Display As
5' UTR -144.70273-0.530 Picture PostScript Text
3' UTR -145.40598-0.243 Picture PostScript Text

The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.

-  Protein Domain and Structure Information
  InterPro Domains: Graphical view of domain structure
IPR026151 - Maspardin

Pfam Domains:
PF00561 - alpha/beta hydrolase fold
PF12697 - Alpha/beta hydrolase family

SCOP Domains:
53474 - alpha/beta-Hydrolases

ModBase Predicted Comparative 3D Structure on Q9NZD8
The pictures above may be empty if there is no ModBase structure for the protein. The ModBase structure frequently covers just a fragment of the protein. You may be asked to log onto ModBase the first time you click on the pictures. It is simplest after logging in to just click on the picture again to get to the specific info on that model.

-  Orthologous Genes in Other Species
  Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
MouseRatZebrafishD. melanogasterC. elegansS. cerevisiae
No orthologGenome BrowserGenome BrowserNo orthologNo orthologNo ortholog
Gene DetailsGene Details    
Gene SorterGene Sorter    
 Protein SequenceProtein Sequence   

-  Gene Ontology (GO) Annotations with Structured Vocabulary
  Molecular Function:
GO:0005515 protein binding
GO:0042609 CD4 receptor binding

Biological Process:
GO:0050851 antigen receptor-mediated signaling pathway

Cellular Component:
GO:0005737 cytoplasm
GO:0005768 endosome
GO:0005794 Golgi apparatus
GO:0005829 cytosol
GO:0010008 endosome membrane
GO:0016020 membrane
GO:0030140 trans-Golgi network transport vesicle
GO:0043231 intracellular membrane-bounded organelle

-  Descriptions from all associated GenBank mRNAs
  AK172849 - Homo sapiens cDNA FLJ24010 fis, clone KAT07969, highly similar to Homo sapiens acid cluster protein 33 (ACP33).
BC000244 - Homo sapiens spastic paraplegia 21 (autosomal recessive, Mast syndrome), mRNA (cDNA clone MGC:816 IMAGE:3357388), complete cds.
AF208861 - Homo sapiens BM-019 mRNA, complete cds.
AF212231 - Homo sapiens GL010 mRNA, complete cds.
AK123725 - Homo sapiens cDNA FLJ41731 fis, clone HLUNG2017286, highly similar to Homo sapiens BM-019 mRNA.
AK225527 - Homo sapiens mRNA for acid cluster protein 33 variant, clone: KAT07969.
AK301362 - Homo sapiens cDNA FLJ52907 complete cds, highly similar to Maspardin.
AK312943 - Homo sapiens cDNA, FLJ93395.
HQ447370 - Synthetic construct Homo sapiens clone IMAGE:100070691; CCSB003392_04 spastic paraplegia 21 (autosomal recessive, Mast syndrome) (SPG21) gene, encodes complete protein.
KJ893890 - Synthetic construct Homo sapiens clone ccsbBroadEn_03284 SPG21 gene, encodes complete protein.
AB464239 - Synthetic construct DNA, clone: pF1KB8128, Homo sapiens SPG21 gene for spastic paraplegia 21, without stop codon, in Flexi system.
CU674096 - Synthetic construct Homo sapiens gateway clone IMAGE:100018820 5' read SPG21 mRNA.
JD355520 - Sequence 336544 from Patent EP1572962.
JD053262 - Sequence 34286 from Patent EP1572962.
JD279969 - Sequence 260993 from Patent EP1572962.
JD396457 - Sequence 377481 from Patent EP1572962.
JD336752 - Sequence 317776 from Patent EP1572962.

-  Other Names for This Gene
  Alternate Gene Symbols: ACP33, B4DW44, BM-019, GL010, NM_016630, NP_057714, Q6ZMB6, Q9NZD8, SPG21_HUMAN
UCSC ID: uc002aoe.3
RefSeq Accession: NM_016630
Protein: Q9NZD8 (aka SPG21_HUMAN)
CCDS: CCDS10198.1

-  GeneReviews for This Gene
  GeneReviews article(s) related to gene SPG21:
hsp (Hereditary Spastic Paraplegia Overview)

-  Gene Model Information
category: coding nonsense-mediated-decay: no RNA accession: NM_016630.3
exon count: 9CDS single in 3' UTR: no RNA size: 1815
ORF size: 927CDS single in intron: no Alignment % ID: 100.00
txCdsPredict score: 2054.00frame shift in genome: no % Coverage: 99.06
has start codon: yes stop codon in genome: no # of Alignments: 1
has end codon: yes retained intron: no # AT/AC introns 0
selenocysteine: no end bleed into intron: 0# strange splices: 0
Click here for a detailed description of the fields of the table above.

-  Methods, Credits, and Use Restrictions
  Click here for details on how this gene model was made and data restrictions if any.