FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Gene: Dmel\qless
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General Information
Symbol
Dmel\qless
Species
D. melanogaster
Name
qless
Annotation Symbol
CG31005
Feature Type
protein_coding_gene
FlyBase ID
FBgn0051005
Gene Model Status
Current
Stock Availability
11 publicly available
Gene Summary
qless (qless) encodes a catalytic subunit of the mitochondrial prenyl diphosphate synthase complex that sequentially transfers isopentenyl diphosphate to farnesyl diphosphate to produce all-trans-polyprenyl diphosphate of varying chain length. It catalyzes the first step in the synthesis of the isoprenoid side chain of Coenzyme Q (ubiquinone), a lipid component of the mitochondrial electron transport chain. [Date last reviewed: 2018-11-15] (FlyBase Gene Snapshot)
All Summaries
Key Links
Genomic Location
Cytogenetic map
100B8-100B8
Sequence location
Recombination map
3-102
RefSeq locus
NT_033777 REGION:31236035..31252608
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 (8 terms)
Molecular Function (2 terms)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
enables prenyl diphosphate synthase activity
inferred from mutant phenotype
(Grant et al., 2010)
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
enables prenyl diphosphate synthase activity
traceable author statement
(Fernández-Ayala et al., 2025)
enables prenyltransferase activity
inferred from biological aspect of ancestor with PANTHER:PTN000243362
(GO Reference Genome Project, 2011-)
inferred from electronic annotation with InterPro:IPR000092
(InterPro Project Members, 2004-)
Biological Process (2 terms)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
involved_in ubiquinone biosynthetic process
inferred from mutant phenotype
(Fernández-Ayala et al., 2025, Grant et al., 2010)
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
involved_in isoprenoid biosynthetic process
inferred from electronic annotation with InterPro:IPR000092
(InterPro Project Members, 2004-)
inferred from biological aspect of ancestor with PANTHER:PTN000243362
(GO Reference Genome Project, 2011-)
involved_in ubiquinone biosynthetic process
inferred from biological aspect of ancestor with PANTHER:PTN000243365
(GO Reference Genome Project, 2011-)
Cellular Component (4 terms)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (4 terms)
CV Term
Evidence
References
part_of heterotetrameric polyprenyl diphosphate synthase complex
inferred from sequence or structural similarity with UniProtKB:Q5T2R2
(Gene Ontology Curators, 2002-)
is_active_in mitochondrial inner membrane
traceable author statement
(Fernández-Ayala et al., 2014)
is_active_in mitochondrion
inferred from biological aspect of ancestor with PANTHER:PTN000243365
(GO Reference Genome Project, 2011-)
part_of polyprenyl diphosphate synthase complex
inferred from biological aspect of ancestor with PANTHER:PTN000243365
(GO Reference Genome Project, 2011-)
Gene Group (FlyBase)
Pathway (FlyBase)
Protein Family (UniProt)
-
Protein Signatures (InterPro)
Summaries
Gene Snapshot
qless (qless) encodes a catalytic subunit of the mitochondrial prenyl diphosphate synthase complex that sequentially transfers isopentenyl diphosphate to farnesyl diphosphate to produce all-trans-polyprenyl diphosphate of varying chain length. It catalyzes the first step in the synthesis of the isoprenoid side chain of Coenzyme Q (ubiquinone), a lipid component of the mitochondrial electron transport chain. [Date last reviewed: 2018-11-15]
Gene Group (FlyBase)
ISOPRENYL PYROPHOSPHATE SYNTHASES -
Isoprenyl pyrophosphate synthases (IPPSs) are responsible for the synthesis of linear isoprenyl pyrophosphates. They can be classified as cis- or trans-isoprenyl pyrophosphate synthases according to the stereochemical outcome of their products. All-trans C[[10]] geranyl pyrophosphate (GPP) and C[[15]] farnesyl pyrophosphate (FPP) are synthesized by trans-type geranyl pyrophosphate synthase and farnesyl pyrophosphate synthase, respectively. Starting from FPP, a variety of different chain-length all-trans-isoprenyl pyrophosphates and trans,cis-isoprenyl pyrophosphates are generated by the corresponding trans-IPPSs or cis-IPPSs. While short-chain (C15) and medium-chain (C50-55) cis-prenyltransferase complexes are homodimeric, long-chain (C70-120) cis-prenyltransferases are formed by a heteromeric subunit assembly of unknown stoichiometry. (Adapted from PMID:12135472, PMID:26216239, PMID:33077723.)
PRENYL DIPHOSPHATE SYNTHASE COMPLEX -
The prenyl diphosphate synthase complex is a heterotetrameric complex located in the mitochondrial inner membrane that possesses polyprenyl diphosphate synthase activity. It is responsible for elongating the isoprenoid chain of ubiquinone (coenzyme Q). (Adapted from PMID:20889762.)
Pathway (FlyBase)
UBIQUINONE BIOSYNTHESIS -
Ubiquinone (also known as Coenzyme Q or CoQ) biosynthesis occurs on the inner mitochondrial membrane and includes four main steps (i) the synthesis of the benzoquinone head ring from tyrosine; (ii) the synthesis of the isoprenoid chain tail; (iii) the condensation of head and tail; and (iv) the sequential modification of the benzoquinone head ring. The isoprenoid chain varies in length depending on the species. In D. melanogaster, there are 3 species of coenzyme Q ranging from 8 to 10 (CoQ8 to CoQ10) isoprenoid units with CoQ9 being the main species. CoQ exists in three oxidation states: fully reduced ubiquinol, the radical semiquinone intermediate and the fully oxidized ubiquinone form allowing it to act as an electron carrier. Its major roles are as an electron shuttle in oxidative phosphorylation and as an antioxidant. (Adapted from PMID:34198496, FBrf0260507 and FBrf0261808.)
Gene Model and Products
Number of Transcripts
2
Number of Unique Polypeptides
1

Please see the JBrowse view of Dmel\qless 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 Q9V9Z3)

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 5.53

Gene model reviewed during 5.47

Gene model reviewed during 5.55

Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
qless-RA
FBtr0085769
NM_170546
3218
436
qless-RB
FBtr0345211
NM_001300690
2784
436
Additional Transcript Data and Comments
Reported size (kB)
Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
UniProt
RefSeq ID
GenBank
qless-PA
FBpp0085131
49.0
436
8.43
Q9V9Z3
NP_733425
AAF57135
qless-PB
FBpp0311406
49.0
436
8.43
Q9V9Z3
NP_001287619
AHN57618
Polypeptides with Identical Sequences

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

436 aa isoforms: qless-PA, qless-PB
Additional Polypeptide Data and Comments
Reported size (kDa)
Comments
External Data
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\qless 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).

-0.68

Transcript Expression
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\qless 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
BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
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
Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
Flygut - An atlas of the Drosophila adult midgut
Images
FlyExpress - Embryonic expression images (BDGP data)
  • Stages(s) 1-3
  • Stages(s) 4-6
  • Stages(s) 11-12
  • Stages(s) 13-16
FlyBase Wiki
Image Based Resources
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 9 )
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 qless
Transgenic constructs containing regulatory region of qless
Aberrations (Deficiencies and Duplications) ( 2 )
Inferred from experimentation ( 2 )
Gene disrupted in
Df(3R)Exel6218
(Grant et al., 2010, Ryder, 2004.4.26)
Df(3R)tll-e
(Grant et al., 2010)
Inferred from location ( 5 )
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) (4)
Hsap\PDSS1
14 of 14
Yes
Yes
Hsap\FDPS
2 of 14
No
No
Hsap\GGPS1
2 of 14
No
No
1  
Hsap\PDSS2
2 of 14
No
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) (4)
Rnor\Pdss1
14 of 14
Yes
Yes
Rnor\Ggps1
2 of 14
No
No
Rnor\Pdss2
2 of 14
No
No
Rnor\Fdps
1 of 14
No
No
Mus musculus (laboratory mouse) (4)
Mmus\Pdss1
13 of 14
Yes
Yes
Mmus\Fdps
2 of 14
No
No
Mmus\Ggps1
2 of 14
No
No
Mmus\Pdss2
2 of 14
No
No
Xenopus tropicalis (Western clawed frog) (6)
Xtro\pdss1
7 of 13
Yes
Yes
Xtro\bend3
1 of 13
No
No
Xtro\ggps1
1 of 13
No
No
Xtro\pdss2
1 of 13
No
No
Xtro\ppp3cb
1 of 13
No
No
Xtro\stx12
1 of 13
No
No
Danio rerio (Zebrafish) (4)
Drer\pdss1
14 of 14
Yes
Yes
Drer\fdps
2 of 14
No
No
Drer\pdss2
2 of 14
No
No
Drer\ggps1
1 of 14
No
No
Caenorhabditis elegans (Nematode, roundworm) (2)
Cele\coq-1
14 of 14
Yes
Yes
Cele\fdps-1
2 of 14
No
No
Anopheles gambiae (African malaria mosquito) (6)
Agam\AgaP_AGAP000591
12 of 12
Yes
Yes
Agam\AgaP_AGAP002069
7 of 12
No
Yes
Agam\AgaP_AGAP006015
2 of 12
No
No
Agam\AgaP_AGAP006016
2 of 12
No
No
Agam\AgaP_AGAP006894
2 of 12
No
No
Agam\AgaP_AGAP007104
2 of 12
No
No
Arabidopsis thaliana (thale-cress) (18)
Atha\GPS1
11 of 13
Yes
Yes
Atha\SPS2
8 of 13
No
Yes
Atha\SPS1
7 of 13
No
Yes
Atha\AT2G18620
4 of 13
No
Yes
Atha\AT3G14510
4 of 13
No
Yes
Atha\AT3G14530
4 of 13
No
Yes
Atha\AT3G20160
4 of 13
No
Yes
Atha\AT3G29430
4 of 13
No
Yes
Atha\AT3G32040
4 of 13
No
Yes
Atha\GGPS1
4 of 13
No
Yes
Atha\GGPS2
4 of 13
No
Yes
Atha\GGPS3
4 of 13
No
Yes
Atha\GGPS4
4 of 13
No
Yes
Atha\GGPS6
4 of 13
No
Yes
Atha\FPS1
2 of 13
No
No
Atha\FPS2
2 of 13
No
No
Atha\GGR
2 of 13
No
No
Atha\AT1G36623
1 of 13
No
Yes
Saccharomyces cerevisiae (Brewer's yeast) (3)
Scer\COQ1
13 of 13
Yes
Yes
Scer\BTS1
2 of 13
No
No
Scer\ERG20
2 of 13
No
No
Schizosaccharomyces pombe (Fission yeast) (4)
Spom\dps1
11 of 12
Yes
Yes
Spom\dlp1
3 of 12
No
Yes
Spom\fps1
2 of 12
No
No
Spom\spo9
2 of 12
No
No
Escherichia coli (enterobacterium) (2)
Ecol\ispB
9 of 11
Yes
Yes
Ecol\ispA
3 of 11
No
Yes
Other Organism Orthologs (via OrthoDB)
Data provided directly from OrthoDB:qless. 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) (3)
Pdss2
4 of 13
qm
4 of 13
Fpps
2 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 ( 1 )
    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?
    PDSS1; decaprenyl diphosphate synthase subunit 1
    14 of 14
    607429
    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
    Linkouts
    BioGRID - A database of protein and genetic interactions.
    DroID - A comprehensive database of gene and protein interactions.
    Pathways
    Signaling Pathways (FlyBase)
    Metabolic Pathways
    FlyBase
    UBIQUINONE BIOSYNTHESIS
    External Links
    KEGG Metabolic Pathways - A collection of manually drawn metabolic pathway maps representing knowledge of molecular interaction, reaction and relation networks.
    Reactome Metabolic Pathways - An open-source, open access, manually curated and peer-reviewed metabolic pathway database.
    External Data
    Linkouts
    KEGG Pathways - A collection of manually drawn pathway maps representing knowledge of molecular interaction, reaction and relation networks.
    Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
    Class of Gene
    Genomic Location and Detailed Mapping Data
    Chromosome (arm)
    3R
    Recombination map
    3-102
    Cytogenetic map
    100B8-100B8
    Sequence location
    FlyBase Computed Cytological Location
    Cytogenetic map
    Evidence for location
    100B8-100B8
    Limits computationally determined from genome sequence between P{PZ}Aph-407028&P{PZ}dcorK215 and P{PZ}l(3)rM731rM731
    Experimentally Determined Cytological Location
    Cytogenetic map
    Notes
    References
    Experimentally Determined Recombination Data
    Location

    3-102

    (FlyBase, 2016)

    3-99.1

    (Comeron et al., 2012)
    Left of (cM)
    Right of (cM)
    Notes
    Stocks and Reagents
    Stocks (11)
    Genomic Clones (21)
    cDNA Clones (83)
     

    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

        Area matching Drosophila EST AI518422.

        (Davies, 2001.3.15)
        Relationship to Other Genes
        Source for database merge of

        Source for merge of: CG31005 anon-WO0118547.422

        (FlyBase, 1996-)

        Source for merge of: CG15565 CG3684

        (FlyBase Genome Annotators, 2002-2003)
        Additional comments

        Annotations CG15565 and CG3684 merged as CG31005 in release 3 of the genome annotation.

        (FlyBase Genome Annotators, 2002-2003)

        Source for merge of CG31005 anon-WO0118547.422 was sequence comparison ( date:051113 ).

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

        Source for identity of: qless CG31005

        (Grant et al., 2010)
        Nomenclature comments
        Etymology
        Synonyms and Secondary IDs (9)
        Datasets (0)
        Study focus (0)
        Experimental Role
        Project
        Project Type
        Title
        Study result (0)
        Result
        Result Type
        Title
        External Crossreferences and Linkouts ( 42 )
        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/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.
        BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
        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
        Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
        Flygut - An atlas of the Drosophila adult midgut
        FlyMet - A comprehensive tissue-specific metabolomics resource for Drosophila.
        iBeetle-Base - RNAi phenotypes in the red flour beetle (Tribolium castaneum)
        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.
        Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
        Reactome Metabolic Pathways - An open-source, open access, manually curated and peer-reviewed metabolic pathway database.
        References (46)