Description: concentrative Na+-nucleoside cotransporter RefSeq Summary (NM_022127): Nucleoside transporters, such as SLC28A3, regulate multiple cellular processes, including neurotransmission, vascular tone, adenosine concentration in the vicinity of cell surface receptors, and transport and metabolism of nucleoside drugs. SLC28A3 shows broad specificity for pyrimidine and purine nucleosides (Ritzel et al., 2001 [PubMed 11032837]).[supplied by OMIM, Mar 2008]. Transcript (Including UTRs) Position: hg18 chr9:86,082,912-86,173,233 Size: 90,322 Total Exon Count: 19 Strand: - Coding Region Position: hg18 chr9:86,082,953-86,145,368 Size: 62,416 Coding Exon Count: 18
ID:S28A3_HUMAN DESCRIPTION: RecName: Full=Solute carrier family 28 member 3; AltName: Full=Concentrative Na(+)-nucleoside cotransporter 3; Short=CNT 3; Short=hCNT3; FUNCTION: Sodium-dependent, pyrimidine- and purine-selective. Involved in the homeostasis of endogenous nucleosides. Exhibits the transport characteristics of the nucleoside transport system cib or N3 subtype (N3/cib) (with marked transport of both thymidine and inosine). Employs a 2:1 sodium/nucleoside ratio. Also able to transport gemcitabine, 3'-azido-3'-deoxythymidine (AZT), ribavirin and 3-deazauridine. BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=21.6 uM for uridine; KM=15.4 uM for cytidine; KM=21.2 uM for thymidine; KM=15.1 uM for adenosine; KM=43 uM for guanosine; KM=52.5 uM for inosine; Vmax=25.8 pmol/min/mg enzyme for uridine uptake; Vmax=32.8 pmol/min/mg enzyme for cytidine uptake; Vmax=24.2 pmol/min/mg enzyme for thymidine uptake; Vmax=30.4 pmol/min/mg enzyme for adenosine uptake; Vmax=51.4 pmol/min/mg enzyme for guanosine uptake; Vmax=44.8 pmol/min/mg enzyme for inosine uptake; SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein (Potential). TISSUE SPECIFICITY: Expressed in pancreas, bone marrow, trachea, mammary gland, liver, prostate, and regions of intestine, brain, lung, placenta, testis, kidney, and heart. INDUCTION: Up-regulated by phorbol myristate acetate (PMA) in HL- 60 cells. SIMILARITY: Belongs to the concentrative nucleoside transporter (CNT) (TC 2.A.41) family.
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on Q9HAS3
Front
Top
Side
The pictures above may be empty if there is no ModBase structure for the protein. The ModBase structure frequently covers just a fragment of the protein. You may be asked to log onto ModBase the first time you click on the pictures. It is simplest after logging in to just click on the picture again to get to the specific info on that model.
Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
Biological Process: GO:0015855 pyrimidine nucleobase transport GO:0015860 purine nucleoside transmembrane transport GO:0015864 pyrimidine nucleoside transport GO:0035725 sodium ion transmembrane transport GO:0072531 pyrimidine-containing compound transmembrane transport GO:1901642 nucleoside transmembrane transport GO:1904823 purine nucleobase transmembrane transport
AK304406 - Homo sapiens cDNA FLJ60396 complete cds, highly similar to Homo sapiens solute carrier family 28 (sodium-coupled nucleoside transporter), member 3 (SLC28A3), mRNA. AF305210 - Homo sapiens concentrative Na+-nucleoside cotransporter hCNT3 (CNT3) mRNA, complete cds. BC093823 - Homo sapiens solute carrier family 28 (sodium-coupled nucleoside transporter), member 3, mRNA (cDNA clone MGC:120858 IMAGE:7939668), complete cds. AK292849 - Homo sapiens cDNA FLJ78185 complete cds, highly similar to Homo sapiens solute carrier family 28 (sodium-coupled nucleoside transporter), member 3 (SLC28A3), mRNA. BC093821 - Homo sapiens solute carrier family 28 (sodium-coupled nucleoside transporter), member 3, mRNA (cDNA clone MGC:120856 IMAGE:7939666), complete cds. AK314039 - Homo sapiens cDNA, FLJ94699, highly similar to Homo sapiens solute carrier family 28 (sodium-coupled nucleoside transporter), member 3 (SLC28A3), mRNA. AK310861 - Homo sapiens cDNA, FLJ17903. KJ899433 - Synthetic construct Homo sapiens clone ccsbBroadEn_08827 SLC28A3 gene, encodes complete protein. AK074678 - Homo sapiens cDNA FLJ90197 fis, clone MAMMA1001418. JD439107 - Sequence 420131 from Patent EP1572962. JD068186 - Sequence 49210 from Patent EP1572962. JD133624 - Sequence 114648 from Patent EP1572962. KY966278 - Homo sapiens cell line 93T449 B4GALNT1/SLC28A3 isoform2 fusion mRNA, partial sequence. KY966299 - Homo sapiens cell line 94T778 B4GALNT1 isoform2/SLC28A3 fusion mRNA, partial sequence.
Biochemical and Signaling Pathways
Reactome (by CSHL, EBI, and GO)
Protein Q9HAS3 (Reactome details) participates in the following event(s):
R-HSA-109538 Concentrative transport (import) of a nucleoside and two sodium ions by solute carrier family 28 (sodium-coupled nucleoside transporter), member 3 R-HSA-83936 Transport of nucleosides and free purine and pyrimidine bases across the plasma membrane R-HSA-425397 Transport of vitamins, nucleosides, and related molecules R-HSA-425407 SLC-mediated transmembrane transport R-HSA-382551 Transport of small molecules
US Server
Sequence and Links to Tools and Databases 
