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2.A.57.1.1
Equilibrative nucleoside transporter (ENT1) (present in the membranes surrounding the cell as well as eukaryotic organelles) (Lee et al., 2006). Residues 334 and 338 in TMS8 determine the inhibitor sensitivity, protein folding and catalytic turnover (Visser et al., 2007). The porter is inhibited by nanomolar concentrations of various structurally distinct coronary vasodilator drugs, including dipyridamole, dilazep, draflazine, soluflazine and nitrobenzylmercaptopurine ribonucleoside (NBMPR) (Paproski et al., 2008).  It transports the A1 adenosine receptor agonist, tecadenoson (Lepist et al. 2013) and mediates gemcitabine (GEM) and folfirinox uptake, chemotheraputic agents for patients with metastatic pancreatic cancer (Orlandi et al. 2016).  The matricellular protein, cysteine-rich angiogenic inducer 61 (CYR61), negatively regulates synthesis of the nucleoside transporters hENT1 and hCNT3, both of which transport gemcitabine (Hesler et al. 2016). These two transporters as well as ENT2 (TC# 2.A.57.1.8) are able to take up the adenosine analogue, fludarabine (AraFA), used to treat cancer (lymphomas and leukemia) (Gorzkiewicz et al. 2018). NEM modification of Cys(416), which is located at the inner extremity of TM10, results in inhibition of hENT1 uridine transport and NBMPR binding by constraining the protein in its inward-facing conformation (Yao et al. 2018).

Accession Number:Q99808
Protein Name:ENT1 aka hENT1 aka SLC29A1
Length:456
Molecular Weight:50219.00
Species:Homo sapiens (Human) [9606]
Number of TMSs:11
Location1 / Topology2 / Orientation3: Membrane1 / Multi-pass membrane protein2
Substrate Nucleosides

Cross database links:

HOG000007684
Genevestigator: Q99808 Q99808
eggNOG: prNOG15273 NOG249415
RefSeq: NP_001071642.1    NP_001071643.1    NP_001071644.1    NP_001071645.1    NP_004946.1   
Entrez Gene ID: 2030   
Pfam: PF01733   
Drugbank: Drugbank Link   
OMIM: 602193  gene
KEGG: hsa:2030    hsa:2030   

Gene Ontology

GO:0005887 C:integral to plasma membrane
GO:0005624 C:membrane fraction
GO:0005337 F:nucleoside transmembrane transporter activity
GO:0005515 F:protein binding
GO:0006139 P:nucleobase, nucleoside, nucleotide and nucl...
GO:0015858 P:nucleoside transport
GO:0016324 C:apical plasma membrane
GO:0016323 C:basolateral plasma membrane
GO:0071333 P:cellular response to glucose stimulus
GO:0071456 P:cellular response to hypoxia
GO:0007595 P:lactation
GO:0006139 P:nucleobase-containing compound metabolic process
GO:0060079 P:regulation of excitatory postsynaptic membrane potential
GO:0030431 P:sleep
GO:0015862 P:uridine transport

References (19)

[1] “Cloning of a human nucleoside transporter implicated in the cellular uptake of adenosine and chemotherapeutic drugs.”  Griffiths M.et.al.   8986748
[2] “Human intestinal es nucleoside transporter: molecular characterization and nucleoside inhibitory profiles.”  Lum P.Y.et.al.   10755314
[3] “Comparative genomic analysis of equilibrative nucleoside transporters suggests conserved protein structure despite limited sequence identity.”  Sankar N.et.al.   12384580
[4] “Complete sequencing and characterization of 21,243 full-length human cDNAs.”  Ota T.et.al.   14702039
[5] “The DNA sequence and analysis of human chromosome 6.”  Mungall A.J.et.al.   14574404
[6] “The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).”  The MGC Project Teamet.al.   15489334
[7] “A quantitative atlas of mitotic phosphorylation.”  Dephoure N.et.al.   18669648
[8] “Mass-spectrometric identification and relative quantification of N-linked cell surface glycoproteins.”  Wollscheid B.et.al.   19349973
[9] “The consensus coding sequences of human breast and colorectal cancers.”  Sjoeblom T.et.al.   16959974
[10] “Cloning of a human nucleoside transporter implicated in the cellular uptake of adenosine and chemotherapeutic drugs.”  Griffiths M.et.al.   8986748
[11] “Human intestinal es nucleoside transporter: molecular characterization and nucleoside inhibitory profiles.”  Lum P.Y.et.al.   10755314
[12] “Comparative genomic analysis of equilibrative nucleoside transporters suggests conserved protein structure despite limited sequence identity.”  Sankar N.et.al.   12384580
[13] “Localization of human equilibrative nucleoside transporters, hENT1 and hENT2, in renal epithelial cells.”  Mangravite L.M.et.al.   12527552
[14] “Complete sequencing and characterization of 21,243 full-length human cDNAs.”  Ota T.et.al.   14702039
[15] “The DNA sequence and analysis of human chromosome 6.”  Mungall A.J.et.al.   14574404
[16] “The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).”  The MGC Project Teamet.al.   15489334
[17] “A quantitative atlas of mitotic phosphorylation.”  Dephoure N.et.al.   18669648
[18] “Mass-spectrometric identification and relative quantification of N-linked cell surface glycoproteins.”  Wollscheid B.et.al.   19349973
[19] “The consensus coding sequences of human breast and colorectal cancers.”  Sjoeblom T.et.al.   16959974

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FASTA formatted sequence
1:	MTTSHQPQDR YKAVWLIFFM LGLGTLLPWN FFMTATQYFT NRLDMSQNVS LVTAELSKDA 
61:	QASAAPAAPL PERNSLSAIF NNVMTLCAML PLLLFTYLNS FLHQRIPQSV RILGSLVAIL 
121:	LVFLITAILV KVQLDALPFF VITMIKIVLI NSFGAILQGS LFGLAGLLPA SYTAPIMSGQ 
181:	GLAGFFASVA MICAIASGSE LSESAFGYFI TACAVIILTI ICYLGLPRLE FYRYYQQLKL 
241:	EGPGEQETKL DLISKGEEPR AGKEESGVSV SNSQPTNESH SIKAILKNIS VLAFSVCFIF 
301:	TITIGMFPAV TVEVKSSIAG SSTWERYFIP VSCFLTFNIF DWLGRSLTAV FMWPGKDSRW 
361:	LPSLVLARLV FVPLLLLCNI KPRRYLTVVF EHDAWFIFFM AAFAFSNGYL ASLCMCFGPK 
421:	KVKPAEAETA GAIMAFFLCL GLALGAVFSF LFRAIV