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General Information
Symbol
Dmel\Shab
Species
D. melanogaster
Name
Shaker cognate b
Annotation Symbol
CG43128
Feature Type
FlyBase ID
FBgn0262593
Gene Model Status
Stock Availability
Gene Snapshot
Shaker cognate b (Shab) encodes a member of the Sh family and the structural alpha subunit of a delayed rectifier K[+] channel (Kv2). The product of Shab channel functions to regulate excitability in neurons and muscles, and transmitter release. [Date last reviewed: 2019-03-14]
Also Known As
dShab, Kv2
Key Links
Genomic Location
Cytogenetic map
Sequence location
3L:2,895,017..2,959,579 [+]
Recombination map
3-5
Sequence
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
GO Summary Ribbons
Protein Family (UniProt)
Belongs to the potassium channel family. B (Shab) (TC 1.A.1.2) subfamily. Shab sub-subfamily. (P17970)
Molecular Function (GO)
[Detailed GO annotations]
Summaries
Gene Group (FlyBase)
VOLTAGE-GATED POTASSIUM CHANNEL - ALPHA SUBUNITS -
Voltage-gated potassium α subunits form homo- or heterotetrameric transmembrane channels specific for potassium which are activated by changes in membrane potential. Kv channel α subunits possess six or seven transmembrane domains. (Adapted from FBrf0224790).
Protein Function (UniProtKB)
Mediates the voltage-dependent potassium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient.
(UniProt, P17970)
Phenotypic Description (Red Book; Lindsley and Zimm 1992)
Shab: Shaker cognate b (J.C. Hall)
Expression in Xenopus oocytes reveals a delayed-rectifier type of potassium current expressed by Shab; the rate of current activation in Shab is somewhat faster than in Shaw.
Summary (Interactive Fly)
slow delayed rectifier K channel - upregulated by light stimulation - functions in light adaptation - regulates excitability in neurons and muscles, and transmitter release
Gene Model and Products
Number of Transcripts
10
Number of Unique Polypeptides
9

Please see the GBrowse view of Dmel\Shab or the JBrowse view of Dmel\Shab 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
Comments on Gene Model
Gene model reviewed during 6.02
Contains low complexity sequences resulting in poly-glycine runs in the translation products.
Low-frequency RNA-Seq exon junction(s) not annotated.
Annotated transcripts do not represent all possible combinations of alternative exons and/or alternative promoters.
Annotated transcripts do not represent all supported alternative splices within 5' UTR.
Gene model reviewed during 5.46
Sequence Ontology: Class of Gene
Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0305201
4598
985
FBtr0305202
4586
1015
FBtr0305203
4756
1011
FBtr0305205
7439
1537
FBtr0305206
7461
1602
FBtr0305208
4439
972
FBtr0305207
5231
799
FBtr0305209
4553
1010
FBtr0333898
7596
1607
FBtr0333899
7491
1602
Additional Transcript Data and Comments
Reported size (kB)
6.8, 4.3 (northern blot)
Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0293731
106.6
985
6.28
FBpp0293732
109.8
1015
6.57
FBpp0293733
110.0
1011
6.41
FBpp0293735
164.6
1537
7.04
FBpp0293736
171.7
1602
6.57
FBpp0293738
105.2
972
6.95
FBpp0293737
87.3
799
6.79
FBpp0293739
109.6
1010
6.69
FBpp0306030
171.8
1607
6.49
FBpp0306031
171.7
1602
6.57
Polypeptides with Identical Sequences

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

1602 aa isoforms: Shab-PI, Shab-PN
Additional Polypeptide Data and Comments
Reported size (kDa)
Comments
The sequence of Shab in Canton-S contains an inserted base relative to Oregon-R leading to a frameshift and a C-terminal extension of the protein.
Co-injection experiments in Xenopus oocytes were used to test for formation of functional heterodimers between Sh subfamily members. In fact, no functional heterodimers (as shown by novel current kinetics) were detected when all pairwise combinations of the four different channel subfamilies (Sh, Shab, Shal, and Shaw) were tested. The independence of each channel system was retained even when all four were co-expressed.
Shab protein was expressed in Xenopus oocytes and characterized with respect to kinetics (rate of macroscopic current activation and inactivation) and voltage sensitivity of steady-state inactivation. Those properties were compared among the Sh subfamily members and found to vary widely. Shab encodes the transient (A current)subtype of potassium channel and appears to function as a homomultimer.
External Data
Subunit Structure (UniProtKB)
Heterotetramer of potassium channel proteins.
(UniProt, P17970)
Domain
The N-terminus may be important in determining the rate of inactivation of the channel while the tail may play a role in modulation of channel activity and/or targeting of the channel to specific subcellular compartments.
(UniProt, P17970)
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\Shab using the Feature Mapper tool.

External Data
Crossreferences
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Linkouts
Gene Ontology (14 terms)
Molecular Function (2 terms)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000164970
(assigned by GO_Central )
traceable author statement
Biological Process (9 terms)
Terms Based on Experimental Evidence (6 terms)
CV Term
Evidence
References
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000164970
(assigned by GO_Central )
inferred from electronic annotation with InterPro:IPR003131
(assigned by InterPro )
Cellular Component (3 terms)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000164970
(assigned by GO_Central )
inferred from sequence or structural similarity
inferred from sequence or structural similarity with FLYBASE:Sh; FB:FBgn0003380
inferred from biological aspect of ancestor with PANTHER:PTN001355853
(assigned by GO_Central )
traceable author statement
Expression Data
Expression Summary Ribbons
Colored tiles in ribbon indicate that expression data has been curated by FlyBase for that anatomical location. Colorless tiles indicate that there is no curated data for that location.
For complete stage-specific expression data, view the modENCODE Development RNA-Seq section under High-Throughput Expression below.
Transcript Expression
northern blot
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
mass spectroscopy
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
Marker for
 
Subcellular Localization
CV Term
Evidence
References
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

GBrowse - Visual display of RNA-Seq signals

View Dmel\Shab in GBrowse 2
RNA-Seq by Region - Search RNA-Seq expression levels by exon or genomic region
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
Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
Images
Alleles, Insertions, and Transgenic Constructs
Classical and Insertion Alleles ( 13 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 8 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of Shab
Transgenic constructs containing regulatory region of Shab
Deletions and Duplications ( 10 )
Phenotypes
Orthologs
Human Orthologs (via DIOPT v7.1)
Homo sapiens (Human) (28)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
9 of 15
Yes
Yes
8 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
 
4 of 15
No
Yes
 
4 of 15
No
Yes
4 of 15
No
Yes
2 of 15
No
No
 
2 of 15
No
No
2 of 15
No
No
 
2 of 15
No
No
1 of 15
No
No
 
1 of 15
No
No
 
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
 
1 of 15
No
No
 
1 of 15
No
No
1 of 15
No
No
 
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Model Organism Orthologs (via DIOPT v7.1)
Mus musculus (laboratory mouse) (27)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
9 of 15
Yes
Yes
8 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
2 of 15
No
No
2 of 15
No
No
2 of 15
No
No
2 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Rattus norvegicus (Norway rat) (25)
6 of 13
Yes
Yes
4 of 13
No
Yes
4 of 13
No
Yes
4 of 13
No
Yes
4 of 13
No
Yes
4 of 13
No
Yes
4 of 13
No
Yes
4 of 13
No
Yes
3 of 13
No
Yes
3 of 13
No
Yes
3 of 13
No
Yes
3 of 13
No
Yes
2 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
Xenopus tropicalis (Western clawed frog) (15)
3 of 12
Yes
Yes
3 of 12
Yes
Yes
3 of 12
Yes
Yes
2 of 12
No
Yes
2 of 12
No
Yes
2 of 12
No
Yes
2 of 12
No
Yes
2 of 12
No
Yes
2 of 12
No
Yes
2 of 12
No
Yes
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
Danio rerio (Zebrafish) (34)
7 of 15
Yes
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
3 of 15
No
Yes
2 of 15
No
No
2 of 15
No
No
2 of 15
No
No
2 of 15
No
No
2 of 15
No
No
2 of 15
No
Yes
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
Yes
Caenorhabditis elegans (Nematode, roundworm) (14)
5 of 15
Yes
Yes
3 of 15
No
Yes
3 of 15
No
Yes
3 of 15
No
Yes
3 of 15
No
Yes
2 of 15
No
No
2 of 15
No
Yes
2 of 15
No
No
2 of 15
No
No
1 of 15
No
Yes
1 of 15
No
Yes
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Arabidopsis thaliana (thale-cress) (4)
1 of 9
Yes
No
1 of 9
Yes
No
1 of 9
Yes
Yes
1 of 9
Yes
No
Saccharomyces cerevisiae (Brewer's yeast) (0)
No records found.
Schizosaccharomyces pombe (Fission yeast) (0)
No records found.
Orthologs in Drosophila Species (via OrthoDB v9.1) ( EOG0919017A )
Organism
Common Name
Gene
AAA Syntenic Ortholog
Multiple Dmel Genes in this Orthologous Group
Drosophila melanogaster
fruit fly
Drosophila suzukii
Spotted wing Drosophila
Drosophila simulans
Drosophila sechellia
Drosophila sechellia
Drosophila erecta
Drosophila yakuba
Drosophila ananassae
Drosophila pseudoobscura pseudoobscura
Drosophila persimilis
Drosophila persimilis
Drosophila willistoni
Drosophila virilis
Drosophila mojavensis
Drosophila grimshawi
Drosophila grimshawi
Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( EOG0915054K )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Musca domestica
House fly
Glossina morsitans
Tsetse fly
Lucilia cuprina
Australian sheep blowfly
Mayetiola destructor
Hessian fly
Mayetiola destructor
Hessian fly
Aedes aegypti
Yellow fever mosquito
Anopheles darlingi
American malaria mosquito
Anopheles gambiae
Malaria mosquito
Culex quinquefasciatus
Southern house mosquito
Orthologs in non-Dipteran Insects (via OrthoDB v9.1) ( EOG090W0A3H )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Bombyx mori
Silkmoth
Danaus plexippus
Monarch butterfly
Heliconius melpomene
Postman butterfly
Apis florea
Little honeybee
Apis mellifera
Western honey bee
Apis mellifera
Western honey bee
Apis mellifera
Western honey bee
Bombus impatiens
Common eastern bumble bee
Bombus impatiens
Common eastern bumble bee
Bombus terrestris
Buff-tailed bumblebee
Bombus terrestris
Buff-tailed bumblebee
Linepithema humile
Argentine ant
Linepithema humile
Argentine ant
Megachile rotundata
Alfalfa leafcutting bee
Megachile rotundata
Alfalfa leafcutting bee
Nasonia vitripennis
Parasitic wasp
Nasonia vitripennis
Parasitic wasp
Dendroctonus ponderosae
Mountain pine beetle
Tribolium castaneum
Red flour beetle
Pediculus humanus
Human body louse
Rhodnius prolixus
Kissing bug
Cimex lectularius
Bed bug
Acyrthosiphon pisum
Pea aphid
Zootermopsis nevadensis
Nevada dampwood termite
Orthologs in non-Insect Arthropods (via OrthoDB v9.1) ( EOG090X09ZD )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strigamia maritima
European centipede
Ixodes scapularis
Black-legged tick
Stegodyphus mimosarum
African social velvet spider
Tetranychus urticae
Two-spotted spider mite
Daphnia pulex
Water flea
Orthologs in non-Arthropod Metazoa (via OrthoDB v9.1) ( EOG091G0FP3 )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strongylocentrotus purpuratus
Purple sea urchin
Ciona intestinalis
Vase tunicate
Ciona intestinalis
Vase tunicate
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Paralogs
Paralogs (via DIOPT v7.1)
Drosophila melanogaster (Fruit fly) (6)
3 of 10
3 of 10
2 of 10
1 of 10
1 of 10
1 of 10
Human Disease Associations
FlyBase Human Disease Model Reports
Disease Model Summary Ribbon
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 0 )
Allele
Disease
Evidence
References
Potential Models Based on Orthology ( 2 )
Modifiers Based on Experimental Evidence ( 0 )
Allele
Disease
Interaction
References
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
 
Disease Associations of Human Orthologs (via DIOPT v7.1 and OMIM)
Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
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
esyN Network Diagram
Interactions Browser
Summary of Genetic Interactions
esyN Network Diagram
esyN Network Key:
Suppression
Enhancement

Please look at the allele data for full details of the genetic interactions
Starting gene(s)
Interaction type
Interacting gene(s)
Reference
Starting gene(s)
Interaction type
Interacting gene(s)
Reference
External Data
Subunit Structure (UniProtKB)
Heterotetramer of potassium channel proteins.
(UniProt, P17970 )
Linkouts
DroID - A comprehensive database of gene and protein interactions.
MIST (genetic) - An integrated Molecular Interaction Database
Pathways
Gene Group - Pathway Membership (FlyBase)
External Data
Genomic Location and Detailed Mapping Data
Chromosome (arm)
3L
Recombination map
3-5
Cytogenetic map
Sequence location
3L:2,895,017..2,959,579 [+]
FlyBase Computed Cytological Location
Cytogenetic map
Evidence for location
63A1-63A2
Limits computationally determined from genome sequence between P{PZ}Spn06911 and P{PZ}l(3)0680306803
Experimentally Determined Cytological Location
Cytogenetic map
Notes
References
63A1-63B6
63A-63A
(determined by in situ hybridisation)
Experimentally Determined Recombination Data
Left of (cM)
Right of (cM)
Notes
Stocks and Reagents
Stocks (16)
Genomic Clones (38)
cDNA Clones (37)
 

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 GBrowse for alignment of the cDNAs and ESTs to the gene model.

cDNA clones, fully sequences
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)
RNAi and Array Information
Linkouts
DRSC - Results frm RNAi screens
GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
Antibody Information
Laboratory Generated Antibodies
 
Commercially Available Antibodies
 
Other Information
Relationship to Other Genes
Source for database identify of
Source for identity of: Shab CG1066
Source for database merge of
Source for merge of: Shab CG9965
Additional comments
Annotations CG1066 and CG9965 merged as CG43128 in release 5.32 of the genome annotation.
Other Comments
The role of Shab channels in Drosophila photoreceptors is to dynamically attenuate the light-induced depolarisation and prevent response saturation in bright light.
A null mutation in Shab reduces the voltage-activated delayed sustained current (IK) but does not eliminate it. Observations suggest that IK consists of two components, which are genetically, pharmacalogically and physiologically distinct. These components are IKS (encoded by Shab) and IKF (which defines a new voltage-activated K+ current).
Shab, Shal and Shaw account for virtually all single channel currents.
Shab may encode an 11 pS slowly inactivating K+ channel present in embryonic neurons.
Shab encodes the major delayed rectifier component of the K+ current in both embryonic muscles and neurons.
Yeast two-hybrid system studies demonstrate the association of the hydrophilic N-terminal domains of the genes encoding channel proteins plays an important role in determining the specificity of α subunit association to form heteromultimeric potassium channels.
Expression in Xenopus oocytes reveals a delayed-rectifier type of potassium current expressed by Shab; the rate of current activation in Shab is somewhat faster than in Shaw.
Sh, Shal, Shab and Shaw encode independent channel systems that function independently in Xenopus oocytes.
Shab potassium channel and a mouse brain homolog potassium channel have similar kinetic, voltage sensitive and pharmacological properties. The greatest functional difference is recovery from inactivation.
Although Sh, Shal, Shab and Shaw proteins share a conserved structral organisation, their potassium channel currents (expressed in Xenopus oocytes) differ greatly in individual kinetic properties and voltage sensitivity.
Sh, Shal, Shab and Shaw encode voltage gated potassium channels with widely varying kinetics (rate of macroscopic current activation and inactivation) and voltage sensitivity of steady state inactivation.
Potassium channel diversity could result from an extended gene family as well as from alternate splicing of the Sh primary transcript.
Origin and Etymology
Discoverer
Etymology
Identification
External Crossreferences and Linkouts ( 76 )
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.
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
BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
KEGG Genes - Molecular building blocks of life in the genomic space.
modMine - A data warehouse for the modENCODE project
Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
Linkouts
DroID - A comprehensive database of gene and protein interactions.
DRSC - Results frm RNAi screens
Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
MIST (genetic) - An integrated Molecular Interaction Database
Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
Synonyms and Secondary IDs (11)
Reported As
Secondary FlyBase IDs
  • FBgn0003383
  • FBgn0035381
Datasets (0)
Study focus (0)
Experimental Role
Project
Project Type
Title
References (142)