FB2026_02 , released June 18, 2026
Gene: Dmel\Sps2
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General Information
Symbol
Dmel\Sps2
Species
D. melanogaster
Name
Selenophosphate synthetase 2
Annotation Symbol
CG5025
Feature Type
protein_coding_gene
FlyBase ID
FBgn0032224
Gene Model Status
Current
Stock Availability
12 publicly available
Enzyme Name (EC)
selenide, water dikinase (2.7.9.3)
Gene Summary
Selenophosphate synthetase 2 (Sps2) is essential for selenoprotein biosynthesis. It encodes an enzyme that catalyzes the synthesis of selenophosphate from selenide and/or other selenium metabolites. Selenophosphate is an active selenium donor for the formation of selenocysteine. [Date last reviewed: 2018-11-15] (FlyBase Gene Snapshot)
All Summaries
Also Known As

Dsps2

Key Links
Genomic Location
Cytogenetic map
31D9-31D9
Sequence location
Recombination map
2-41
RefSeq locus
NT_033779 REGION:10342594..10344223
Sequence
Get Decorated FASTA
Genomic Maps
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
NCBI
UCSC
Ensembl
PopFly
Function
Gene Ontology (GO) Annotations (5 terms)
Molecular Function (3 terms)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
enables ATP binding
traceable author statement
(Hirosawa-Takamori et al., 2000)
inferred from electronic annotation with InterPro:IPR004536
(InterPro Project Members, 2004-)
enables purine nucleotide binding
inferred from sequence or structural similarity
(Hirosawa-Takamori et al., 2000)
enables selenide, water dikinase activity
inferred from sequence or structural similarity with UniProtKB:Q99611
(Hirosawa-Takamori et al., 2000)
inferred from sequence or structural similarity with UniProtKB:P49903
(Gene Ontology Curators, 2002-)
inferred from biological aspect of ancestor with PANTHER:PTN000029003
(GO Reference Genome Project, 2011-)
Biological Process (1 term)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
involved_in L-selenocysteine biosynthetic process
inferred from sequence or structural similarity with UniProtKB:Q99611
(Hirosawa-Takamori et al., 2000)
inferred from biological aspect of ancestor with PANTHER:PTN000029003
(GO Reference Genome Project, 2011-)
Cellular Component (1 term)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
is_active_in cytoplasm
inferred from biological aspect of ancestor with PANTHER:PTN000029003
(GO Reference Genome Project, 2011-)
Gene Group (FlyBase)
Protein Family (UniProt)
Belongs to the selenophosphate synthase 1 family. Class I subfamily. (Q9VKY8)
Protein Signatures (InterPro)
Catalytic Activity (EC/Rhea)
selenide, water dikinase activity
hydrogenselenide + ATP + H2O = selenophosphate + AMP + phosphate + 2 H(+) (2.7.9.3)
RHEA 18737:
Summaries
Gene Snapshot
Selenophosphate synthetase 2 (Sps2) is essential for selenoprotein biosynthesis. It encodes an enzyme that catalyzes the synthesis of selenophosphate from selenide and/or other selenium metabolites. Selenophosphate is an active selenium donor for the formation of selenocysteine. [Date last reviewed: 2018-11-15]
Gene Group (FlyBase)
UNCLASSIFIED KINASES -
This group comprises kinases that do not classify under other groups in FlyBase.
SELENOPROTEINS -
Selenoproteins arise from the differential decoding of the UGA stop codon as selenocysteine. Compared with other eukaryotes, arthropods show a reduced complement of selenoproteins. (Adapted from FBrf0216226.)
Protein Function (UniProtKB)
Synthesizes selenophosphate from selenide and ATP.
(UniProt, Q9VKY8)
Gene Model and Products
Number of Transcripts
2
Number of Unique Polypeptides
1

Please see the JBrowse view of Dmel\Sps2 for information on other features

To submit a correction to a gene model please use the Contact FlyBase form

Protein Domains (via Pfam)
Isoform displayed:
Pfam protein domains
InterPro name
classification
start
end
Protein Domains (via SMART)
Isoform displayed:
SMART protein domains
InterPro name
classification
start
end
Structure
Protein 3D structure   (Predicted by AlphaFold)   (AlphaFold entry Q9VKY8)

If you don't see a structure in the viewer, refresh your browser.
Model Confidence:
  • Very high (pLDDT > 90)
  • Confident (90 > pLDDT > 70)
  • Low (70 > pLDDT > 50)
  • Very low (pLDDT < 50)

AlphaFold produces a per-residue confidence score (pLDDT) between 0 and 100. Some regions with low pLDDT may be unstructured in isolation.

Experimentally Determined Structures
Crossreferences
Comments on Gene Model

Gene model reviewed during 5.52

Low-frequency RNA-Seq exon junction(s) not annotated.

Gene model reviewed during 5.42

Stop-codon suppression (UGA as Sec) postulated (FBrf0133278); reflected in predicted polypeptides.

Gene model reviewed during 6.02

Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
Sps2-RA
FBtr0079998
NM_058130
1460
370
Sps2-RC
FBtr0310115
NM_001273400
1352
370
Additional Transcript Data and Comments
Reported size (kB)

1.5 (northern blot)

(Hirosawa-Takamori et al., 2000)
Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
UniProt
RefSeq ID
GenBank
Sps2-PA
FBpp0079588
41.1
370
6.31
Q9VKY8
NP_477478
AAF52918
Sps2-PC
FBpp0301800
41.1
370
6.31
Q9VKY8
NP_001260329
AGB92864
Polypeptides with Identical Sequences

The group(s) of polypeptides indicated below share identical sequence to each other.

370 aa isoforms: Sps2-PA, Sps2-PC
Additional Polypeptide Data and Comments
Reported size (kDa)

370 (aa)

(Hirosawa-Takamori et al., 2000)
Comments
External Data
Subunit Structure (UniProtKB)

Homodimer.

(UniProt, Q9VKY8)
Crossreferences
InterPro - A database of protein families, domains and functional sites
Linkouts
Sequences Consistent with the Gene Model
Mapped Features

Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Sps2 using the Feature Mapper tool.

External Data
Crossreferences
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Linkouts
Expression Data
Testis-specificity index

The testis specificity index was calculated from modENCODE tissue expression data by Vedelek et al., 2018 to indicate the degree of testis enrichment compared to other tissues. Scores range from -2.52 (underrepresented) to 5.2 (very high testis bias).

-0.77

Transcript Expression
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
embryonic stage 1 -- 5
organism | ubiquitous
(Hirosawa-Takamori et al., 2000)
embryonic stage 11 -- 15
presumptive embryonic/larval central nervous system
(Hirosawa-Takamori et al., 2000)
embryonic/larval gut
(Hirosawa-Takamori et al., 2000)
adult stage | female & oogenesis
nurse cell
(Hirosawa-Takamori et al., 2000)
oocyte
(Hirosawa-Takamori et al., 2000)
northern blot
Stage
Tissue/Position (including subcellular localization)
Reference
embryonic stage
(Hirosawa-Takamori et al., 2000)
organism
(Hirosawa-Takamori et al., 2000)
embryonic stage 1 -- 5
organism
(Hirosawa-Takamori et al., 2000)
gastrula stage
midgut primordium
(Hirosawa-Takamori et al., 2000)
embryonic stage 13
presumptive embryonic/larval nervous system
(Hirosawa-Takamori et al., 2000)
presumptive embryonic/larval digestive system
(Hirosawa-Takamori et al., 2000)
larval stage
(Hirosawa-Takamori et al., 2000)
organism
(Hirosawa-Takamori et al., 2000)
adult stage
(Hirosawa-Takamori et al., 2000)
organism
(Hirosawa-Takamori et al., 2000)
adult stage & oogenesis
nurse cell
(Hirosawa-Takamori et al., 2000)
oocyte
(Hirosawa-Takamori et al., 2000)
Additional Descriptive Data

Sps2 transcripts accumulate in the oocyte and levels remain high up to the blastoderm stage. Amount of transcript subsequently decreases, to reappear again in the midgut anlagen of the gastrula. Later, transcripts are enriched in a variety of tissues and organs including the gut and the nervous system.

(Hirosawa-Takamori et al., 2000)
Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
Additional Descriptive Data
Marker for
 
Subcellular Localization
CV Term
Evidence
References
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

JBrowse - Visual display of RNA-Seq signals

View Dmel\Sps2 in JBrowse
RNA-Seq by Region - Search RNA-Seq expression levels by exon or genomic region
Bulk Downloads
RNA-Seq RPKM values for all genes
Reference
See Gelbart and Emmert, 2013 for analysis details and data files for all genes.
Developmental Proteome: Life Cycle
Developmental Proteome: Embryogenesis
External Data and Images
Linkouts
DRscDB - A single-cell RNA-seq resource for data mining and data comparison across species
EMBL-EBI Single Cell Expression Atlas - Single cell expression across species
FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
Flygut - An atlas of the Drosophila adult midgut
Images
FlyBase Wiki
Image Based Resources
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 8 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 7 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of Sps2
Transgenic constructs containing regulatory region of Sps2
Aberrations (Deficiencies and Duplications) ( 2 )
Inferred from experimentation ( 2 )
Gene disrupted in
Df(2L)BSC208
(Madhwani et al., 2024)
Df(2L)J27
(Hirosawa-Takamori et al., 2000)
Inferred from location ( 8 )
Variants
Variant Molecular Consequences
Alleles Representing Disease-Implicated Variants
Phenotypes
Orthologs
Downloads
Download All DIOPT Orthologs
Human Orthologs (via DIOPT v9.1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Source
Compara
Domainoid
eggNOG
Hieranoid
Homologene
Inparanoid
OMA
OrthoDB
OrthoFinder
OrthoInspector
orthoMCL
Panther
Phylome
SonicParanoid
Alignment
Complementation?
Transgene?
Homo sapiens (Human) (2)
Hsap\SEPHS1
8 of 14
Yes
No
1  
Hsap\SEPHS2
8 of 14
Yes
No
Model Organism Orthologs (via DIOPT v9.1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Source
Compara
Domainoid
eggNOG
Hieranoid
Homologene
Inparanoid
OMA
OrthoDB
OrthoFinder
OrthoInspector
orthoMCL
Panther
Phylome
SonicParanoid
Alignment
Complementation?
Transgene?
Rattus norvegicus (Norway rat) (2)
Rnor\Sephs1
8 of 14
Yes
No
Rnor\Sephs2
1 of 14
No
Yes
Mus musculus (laboratory mouse) (2)
Mmus\Sephs2
8 of 14
Yes
No
Mmus\Sephs1
7 of 14
No
No
Xenopus tropicalis (Western clawed frog) (2)
Xtro\sephs1
6 of 13
Yes
No
Xtro\sephs3
3 of 13
No
No
Danio rerio (Zebrafish) (2)
Drer\sephs1
8 of 14
Yes
No
Drer\sephs3
6 of 14
No
No
Caenorhabditis elegans (Nematode, roundworm) (1)
Cele\seld-1
8 of 14
Yes
No
Anopheles gambiae (African malaria mosquito) (2)
Agam\AgaP_AGAP011375
8 of 12
Yes
Yes
Agam\AgaP_AGAP007967
7 of 12
No
No
Arabidopsis thaliana (thale-cress) (0)
Saccharomyces cerevisiae (Brewer's yeast) (0)
Schizosaccharomyces pombe (Fission yeast) (0)
Escherichia coli (enterobacterium) (2)
Ecol\selD
10 of 11
Yes
No
Ecol\purM
1 of 11
No
No
Other Organism Orthologs (via OrthoDB)
Data provided directly from OrthoDB:Sps2. Refer to their site for version information.
Paralogs
Downloads
Download All DIOPT Paralogs
Paralogs (via DIOPT v9.1)
Gene Symbol
Score
Source
Compara
Domainoid
eggNOG
Homologene
Inparanoid
OMA
OrthoDB
OrthoFinder
OrthoInspector
orthoMCL
Panther
Phylome
SonicParanoid
Alignment
Drosophila melanogaster (Fruit fly) (1)
Sps1
10 of 13
Human Disease Associations
FlyBase Human Disease Model Reports
    Disease Ontology (DO) Annotations
    Models Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Evidence
    References
    Potential Models Based on Orthology ( 0 )
    Human Ortholog
    Disease
    Evidence
    References
    Modifiers Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Interaction
    References
    Disease Associations of Human Orthologs (via DIOPT v9.1 and OMIM)
    Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
    Homo sapiens (Human)
    Gene name
    Score
    OMIM
    OMIM Phenotype
    DO term
    Complementation?
    Transgene?
    SEPHS1; selenophosphate synthetase 1
    8 of 14
    600902
       
      SEPHS2; selenophosphate synthetase 2
      8 of 14
      606218
          Functional Complementation Data
          Functional complementation data is computed by FlyBase using a combination of the orthology data obtained from DIOPT and OrthoDB and the allele-level genetic interaction data curated from the literature.
          Interactions
          Summary of Physical Interactions
          Interaction Browsers
          Summary of Genetic Interactions
          Interaction Browsers
          Starting gene(s)
          Interaction type
          Interacting gene(s)
          Reference
          Starting gene(s)
          Interaction type
          Interacting gene(s)
          Reference
          External Data
          Subunit Structure (UniProtKB)
          Homodimer.
          (UniProt, Q9VKY8 )
          Linkouts
          BioGRID - A database of protein and genetic interactions.
          DroID - A comprehensive database of gene and protein interactions.
          MIST (protein-protein) - An integrated Molecular Interaction Database
          Pathways
          Signaling Pathways (FlyBase)
          Metabolic Pathways
          FlyBase
          External Links
          FlyCyc Pathways - Pathways from a BioCyc PGDB for Dmel
          KEGG Metabolic Pathways - A collection of manually drawn metabolic pathway maps representing knowledge of molecular interaction, reaction and relation networks.
          External Data
          Linkouts
          KEGG Pathways - A collection of manually drawn pathway maps representing knowledge of molecular interaction, reaction and relation networks.
          Class of Gene
          Genomic Location and Detailed Mapping Data
          Chromosome (arm)
          2L
          Recombination map
          2-41
          Cytogenetic map
          31D9-31D9
          Sequence location
          FlyBase Computed Cytological Location
          Cytogenetic map
          Evidence for location
          31D9-31D9
          Limits computationally determined from genome sequence between P{lacW}RnrLk06709 and P{lacW}KdelRk00311
          Experimentally Determined Cytological Location
          Cytogenetic map
          Notes
          References
          Experimentally Determined Recombination Data
          Location

          2-41

          (FlyBase, 2016)

          2-35.2

          (Comeron et al., 2012)
          Left of (cM)
          Right of (cM)
          Notes
          Stocks and Reagents
          Stocks (12)
          Genomic Clones (22)
          cDNA Clones (8)
           

          Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see JBrowse for alignment of the cDNAs and ESTs to the gene model.

          cDNA clones, fully sequenced
          BDGP DGC clones
          Other clones
            Drosophila Genomics Resource Center cDNA clones

            For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.

            cDNA Clones, End Sequenced (ESTs)
            BDGP DGC clones
            Other clones
            RNAi and Array Information
            Linkouts
            DRSC - Results frm RNAi screens
            Antibody Information
            Laboratory Generated Antibodies
             
            Commercially Available Antibodies
             
            Cell Line Information
            Publicly Available Cell Lines
             
              Other Stable Cell Lines
               
                Other Comments
                Relationship to Other Genes
                Source for database merge of
                Additional comments

                Source for identity of Sps2 CG5025 was sequence comparison ( date:000608 ).

                (FlyBase, 1996-)
                Nomenclature History
                Source for database identify of

                Source for identity of: Sps2 CG5025

                (FlyBase, 1996-)
                Nomenclature comments
                Etymology
                Synonyms and Secondary IDs (10)
                Datasets (0)
                Study focus (0)
                Experimental Role
                Project
                Project Type
                Title
                Study result (0)
                Result
                Result Type
                Title
                External Crossreferences and Linkouts ( 51 )
                Sequence Crossreferences
                NCBI Gene - Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes, and links to genome-, phenotype-, and locus-specific resources worldwide.
                GenBank Nucleotide - A collection of sequences from several sources, including GenBank, RefSeq, TPA, and PDB.
                GenBank Protein - A collection of sequences from several sources, including translations from annotated coding regions in GenBank, RefSeq and TPA, as well as records from SwissProt, PIR, PRF, and PDB.
                RefSeq - A comprehensive, integrated, non-redundant, well-annotated set of reference sequences including genomic, transcript, and protein.
                UniProt/GCRP - The gene-centric reference proteome (GCRP) provides a 1:1 mapping between genes and UniProt accessions in which a single 'canonical' isoform represents the product(s) of each protein-coding gene.
                UniProt/Swiss-Prot - Manually annotated and reviewed records of protein sequence and functional information
                UniProt/TrEMBL - Automatically annotated and unreviewed records of protein sequence and functional information
                Other crossreferences
                AlphaFold DB - AlphaFold provides open access to protein structure predictions for the human proteome and other key proteins of interest, to accelerate scientific research.
                DRscDB - A single-cell RNA-seq resource for data mining and data comparison across species
                EMBL-EBI Single Cell Expression Atlas - Single cell expression across species
                FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
                FlyMine - An integrated database for Drosophila genomics
                InterPro - A database of protein families, domains and functional sites
                KEGG Genes - Molecular building blocks of life in the genomic space.
                MARRVEL_MODEL - MARRVEL (model organism gene)
                Linkouts
                BioGRID - A database of protein and genetic interactions.
                Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
                DroID - A comprehensive database of gene and protein interactions.
                DRSC - Results frm RNAi screens
                Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
                FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
                FlyCyc Genes - Genes from a BioCyc PGDB for Dmel
                FlyCyc Pathways - Pathways from a BioCyc PGDB for Dmel
                Flygut - An atlas of the Drosophila adult midgut
                KEGG Metabolic Pathways - A collection of manually drawn metabolic pathway maps representing knowledge of molecular interaction, reaction and relation networks.
                KEGG Pathways - A collection of manually drawn pathway maps representing knowledge of molecular interaction, reaction and relation networks.
                MIST (protein-protein) - An integrated Molecular Interaction Database
                References (52)