FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Gene: Dmel\Pi4KIIα
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General Information
Symbol
Dmel\Pi4KIIα
Species
D. melanogaster
Name
Phosphatidylinositol 4-kinase II α
Annotation Symbol
CG2929
Feature Type
protein_coding_gene
FlyBase ID
FBgn0037339
Gene Model Status
Current
Stock Availability
13 publicly available
Enzyme Name (EC)
1-phosphatidylinositol 4-kinase (2.7.1.67)
Gene Summary
Pi4KIIα (Pi4KIIα) encodes a lipid kinase that synthesizes phosphatidylinositol 4-phosphate from phosphatidylinositol. It contributes to membrane trafficking in the larval salivary gland. [Date last reviewed: 2019-03-14] (FlyBase Gene Snapshot)
All Summaries
Also Known As

PI4KII

Key Links
Genomic Location
Cytogenetic map
83B1-83B2
Sequence location
Recombination map
3-47.5
RefSeq locus
NT_033777 REGION:5557663..5563652
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 (9 terms)
Molecular Function (1 term)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
enables 1-phosphatidylinositol 4-kinase activity
inferred from direct assay
(Burgess et al., 2012, Barylko et al., 2002)
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
enables 1-phosphatidylinositol 4-kinase activity
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
inferred from electronic annotation with InterPro:IPR039756
(InterPro Project Members, 2004-)
Biological Process (5 terms)
Terms Based on Experimental Evidence (5 terms)
CV Term
Evidence
References
involved_in endosome organization
inferred from mutant phenotype
(Burgess et al., 2012)
involved_in Golgi organization
inferred from mutant phenotype
(Tan et al., 2014)
involved_in phosphatidylinositol phosphate biosynthetic process
inferred from direct assay
(Barylko et al., 2002)
involved_in secretory granule localization
inferred from mutant phenotype
(Burgess et al., 2012)
involved_in secretory granule organization
inferred from mutant phenotype
(Burgess et al., 2012)
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
involved_in endosome organization
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
involved_in Golgi organization
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
involved_in phosphatidylinositol phosphate biosynthetic process
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
Cellular Component (3 terms)
Terms Based on Experimental Evidence (2 terms)
CV Term
Evidence
References
located_in plasma membrane
inferred from high throughput direct assay
(Tan et al., 2009)
located_in trans-Golgi network
inferred from direct assay
(Burgess et al., 2012)
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
is_active_in endosome
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
is_active_in plasma membrane
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
is_active_in trans-Golgi network
inferred from biological aspect of ancestor with PANTHER:PTN000305230
(GO Reference Genome Project, 2011-)
Gene Group (FlyBase)
Protein Family (UniProt)
-
Protein Signatures (InterPro)
Catalytic Activity (EC/Rhea)
1-phosphatidylinositol 4-kinase activity
a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol) + ATP = a 1,2-diacyl- sn-glycero-3-phospho-(1D-myo-inositol 4-phosphate) + ADP + H(+) (2.7.1.67)
RHEA 19877:
Summaries
Gene Snapshot
Pi4KIIα (Pi4KIIα) encodes a lipid kinase that synthesizes phosphatidylinositol 4-phosphate from phosphatidylinositol. It contributes to membrane trafficking in the larval salivary gland. [Date last reviewed: 2019-03-14]
Gene Group (FlyBase)
PHOSPHATIDYLINOSITOL 4 KINASES -
Phosphatidylinositol 4 kinases catalyze the phosphorylation of phosphatidylinositol (PI) or specific mono phosphate derivatives of PI at position 4 on the inositol ring to generate PI4P, PI(3,4)P[[2]] or PI(4,5)P[[2]]. The resulting phosphoinositides can then act as signalling molecules to mediate/regulate a range of cellular and physiological processes, including cell polarity, cell migration, autophagy, growth, development, and ageing. (Adapted from FBrf0227909.)
Summary (Interactive Fly)

Type II phosphatidylinositol 4-kinase (PI4KII) produces the lipid phosphatidylinositol 4-phosphate, a key regulator of membrane trafficking - critical for apical membrane transport events required for rhabdomere biogenesis

Gene Model and Products
Number of Transcripts
5
Number of Unique Polypeptides
4

Please see the JBrowse view of Dmel\Pi4KIIα 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 Q9VND3)

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 6.32

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

Gene model reviewed during 5.48

Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
Pi4KIIα-RA
FBtr0078756
NM_169063
3122
710
Pi4KIIα-RB
FBtr0078755
NM_169064
2565
563
Pi4KIIα-RC
FBtr0078757
NM_206432
3095
710
Pi4KIIα-RE
FBtr0479746
NM_001382052
2718
480
Pi4KIIα-RF
FBtr0479926
NM_001382053
2044
457
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
Pi4KIIα-PA
FBpp0089178
79.0
710
6.09
Q9VND3
NP_730944
AAF52010
Pi4KIIα-PB
FBpp0078404
63.1
563
8.36
Q8I0B7
NP_730945
AAN13242
Pi4KIIα-PC
FBpp0089179
79.0
710
6.09
Q9VND3
NP_996154
AAS65098
Pi4KIIα-PE
FBpp0428089
54.3
480
8.74
ACZ94809
Pi4KIIα-PF
FBpp0428258
51.8
457
9.59
QJC18441
Polypeptides with Identical Sequences

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

710 aa isoforms: Pi4KIIα-PA, Pi4KIIα-PC
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\Pi4KIIα 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).

3.49

Transcript Expression
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
embryonic stage 1 -- 3
organism

Comment: maternally deposited

(Fisher et al., 2012)
Additional Descriptive Data
Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
third instar larval stage
embryonic/larval salivary gland

Comment: punctate dsitribution

(Burgess et al., 2012)
Additional Descriptive Data

Pi4KIIα is enriched in salivary glands.

(Burgess et al., 2012)
Marker for
 
Subcellular Localization
CV Term
Evidence
References
located_in plasma membrane
inferred from high throughput direct assay
(Tan et al., 2009)
located_in trans-Golgi network
inferred from direct assay
(Burgess et al., 2012)
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

JBrowse - Visual display of RNA-Seq signals

View Dmel\Pi4KIIα 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
FlyBase Wiki
Image Based Resources
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 6 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 16 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of Pi4KIIα
Transgenic constructs containing regulatory region of Pi4KIIα
Aberrations (Deficiencies and Duplications) ( 2 )
Inferred from experimentation ( 2 )
Gene disrupted in
Df(3R)730
(Burgess et al., 2012)
Df(3R)Exel6144
(Ryder, 2004.4.26)
Inferred from location ( 7 )
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\PI4K2A
12 of 14
Yes
Yes
1  
Hsap\PI4K2B
11 of 14
No
Yes
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\Pi4k2a
12 of 14
Yes
Yes
Rnor\Pi4k2b
11 of 14
No
Yes
Mus musculus (laboratory mouse) (2)
Mmus\Pi4k2a
12 of 14
Yes
Yes
Mmus\Pi4k2b
11 of 14
No
Yes
Xenopus tropicalis (Western clawed frog) (3)
Xtro\pi4k2a
9 of 13
Yes
Yes
Xtro\pi4k2b
8 of 13
No
Yes
Xtro\vdac1
1 of 13
No
No
Danio rerio (Zebrafish) (2)
Drer\pi4k2a
12 of 14
Yes
Yes
Drer\pi4k2b
11 of 14
No
Yes
Caenorhabditis elegans (Nematode, roundworm) (2)
Cele\ZC8.6
12 of 14
Yes
Yes
Cele\C56A3.8
5 of 14
No
Yes
Anopheles gambiae (African malaria mosquito) (1)
Agam\AgaP_AGAP003121
11 of 12
Yes
Yes
Arabidopsis thaliana (thale-cress) (11)
Atha\AT1G26270
5 of 13
Yes
Yes
Atha\AT1G13640
4 of 13
No
Yes
Atha\PI4K GAMMA 7
4 of 13
No
Yes
Atha\AT1G64460
3 of 13
No
Yes
Atha\AT3G56600
3 of 13
No
Yes
Atha\AT5G24240
3 of 13
No
Yes
Atha\PI4K GAMMA 1
3 of 13
No
Yes
Atha\PI4K GAMMA 4
3 of 13
No
Yes
Atha\AT1G27570
1 of 13
No
No
Atha\AT1G67635
1 of 13
No
Yes
Atha\AT3G43950
1 of 13
No
Yes
Saccharomyces cerevisiae (Brewer's yeast) (1)
Scer\LSB6
11 of 13
Yes
Yes
Schizosaccharomyces pombe (Fission yeast) (1)
Spom\lsb6
10 of 12
Yes
Yes
Escherichia coli (enterobacterium) (0)
Other Organism Orthologs (via OrthoDB)
Data provided directly from OrthoDB:Pi4KIIα. Refer to their site for version information.
Paralogs
Downloads
Download All DIOPT Paralogs
Paralogs (via DIOPT v9.1)
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?
    PI4K2A; phosphatidylinositol 4-kinase type 2 alpha
    12 of 14
    609763
       
      PI4K2B; phosphatidylinositol 4-kinase type 2 beta
      11 of 14
      612101
          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
          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.
          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.
          SignaLink - A signaling pathway resource with multi-layered regulatory networks.
          Class of Gene
          Genomic Location and Detailed Mapping Data
          Chromosome (arm)
          3R
          Recombination map
          3-47.5
          Cytogenetic map
          83B1-83B2
          Sequence location
          FlyBase Computed Cytological Location
          Cytogenetic map
          Evidence for location
          83B1-83B2
          Limits computationally determined from genome sequence between P{PZ}Snr101319&P{PZ}Itp-r83A05616 and P{lacW}Atus1938
          Experimentally Determined Cytological Location
          Cytogenetic map
          Notes
          References
          Experimentally Determined Recombination Data
          Location

          3-47.5

          (FlyBase, 2016)

          3-44.1

          (Comeron et al., 2012)
          Left of (cM)
          Right of (cM)
          Notes
          Stocks and Reagents
          Stocks (13)
          Genomic Clones (21)
          cDNA Clones (51)
           

          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
           

          polyclonal

          (Burgess et al., 2012)
          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

              snoRNA:Pi4KIIα-a is encoded in an intron of Pi4KIIα.

              (Graveley et al., 2011)

              Source for identity of Pi4KIIα CG2929 was sequence comparison ( date:020416 ).

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

              Source for identity of: Pi4KIIα CG2929

              (FlyBase, 1996-)
              Nomenclature comments
              Etymology
              Synonyms and Secondary IDs (12)
              Datasets (0)
              Study focus (0)
              Experimental Role
              Project
              Project Type
              Title
              Study result (0)
              Result
              Result Type
              Title
              External Crossreferences and Linkouts ( 71 )
              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
              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
              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)
              Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
              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
              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.
              SignaLink - A signaling pathway resource with multi-layered regulatory networks.
              References (66)