TCDB is operated by the Saier Lab Bioinformatics Group
« See all members of the family


2.A.1.19.6
The polyspecific potential-sensitive organic cation uptake transporter, Oct3 (transport substrates include the neurotoxin 1-methyl-4-phenylpyridinium and monoamine neurotransmitters such as dopamine). Mediates paraquat (herbicide) neurotoxicity (Rappold et al., 2011). SLC22 transporters involved in drug elimination and organ distribution are polyspecific. The cryo-EM structure of SLC22A3 (OCT3) is available (Meyer-Tönnies and Tzvetkov 2023). OCT3 and MATE2 genetic polymorphisms can give rise to poor responses to metformin in type 2 diabetes mellitus (Naem et al. 2024).

Accession Number:O88446
Protein Name:Oct3 aka SLC22A3
Length:551
Molecular Weight:61050.00
Species:Rattus norvegicus (Rat) [10116]
Number of TMSs:12
Location1 / Topology2 / Orientation3: Membrane1 / Multi-pass membrane protein2
Substrate dopamine, N-methyl-4-phenylpyridinium

Cross database links:

RefSeq: NP_062103.1   
Entrez Gene ID: 29504   
Pfam: PF00083   
KEGG: rno:29504   

Gene Ontology

GO:0016021 C:integral to membrane
GO:0005329 F:dopamine transmembrane transporter activity
GO:0005515 F:protein binding
GO:0015651 F:quaternary ammonium group transmembrane tra...
GO:0019534 F:toxin transporter activity
GO:0015872 P:dopamine transport
GO:0015697 P:quaternary ammonium group transport
GO:0055085 P:transmembrane transport

References (2)

[1] “Cloning and functional characterization of a potential-sensitive, polyspecific organic cation transporter (OCT3) most abundantly expressed in placenta.”  Kekuda R.et.al.   9632645
[2] “Identity of the organic cation transporter OCT3 as the extraneuronal monoamine transporter (uptake2) and evidence for the expression of the transporter in the brain.”  Wu X.et.al.   9830022

External Searches:

Analyze:

Predict TMSs (Predict number of transmembrane segments)
Window Size: Angle:  
FASTA formatted sequence
1:	MPTFDQALRK AGEFGRFQRR VFLLLCLTGV TFAFLFVGVV FLGSQPDYYW CRGPRATALA 
61:	ERCAWSPEEE WNLTTPELHV PAERRGQGHC HRYLLEDTNT SSELSCDPLA AFPNRSAPLV 
121:	PCSGDWRYVE THSTIVSQFD LVCGNAWMLD LTQAILNLGF LAGAFTLGYA ADRYGRLIVY 
181:	LISCFGVGIT GVVVAFAPNF SVFVIFRFLQ GVFGKGAWMT CFVIVTEIVG SKQRRIVGIV 
241:	IQMFFTLGII ILPGIAYFTP SWQGIQLAIS LPSFLFLLYY WVVPESPRWL ITRKQGEKAL 
301:	QILRRVAKCN GKHLSSNYSE ITVTDEEVSN PSCLDLVRTP QMRKCTLILM FAWFTSAVVY 
361:	QGLVMRLGLI GGNLYMDFFI SGLVELPGAL LILLTIERLG RRLPFAASNI VAGVSCLVTA 
421:	FLPEGIPWLR TTVATLGRLG ITMAFEIVYL VNSELYPTTL RNFGVSLCSG LCDFGGIIAP 
481:	FLLFRLAAIW LELPLIIFGI LASVCGGLVM LLPETKGIAL PETVEDVEKL GSSQLHQCGR 
541:	KKKTQVSTSN V