Reviewed, UniProtKB/Swiss-Prot P55060 (XPO2_HUMAN)

Names and origin

Protein names

Recommended name:
    Exportin-2
      Short name=Exp2
Alternative name(s):
    Importin-alpha re-exporter
    Chromosome segregation 1-like protein
    Cellular apoptosis susceptibility protein

Gene names

Name:	CSE1L
Synonyms:	CAS, XPO2

Organism

Homo sapiens (Human)

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	971 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Export receptor for importin-alpha. Mediates importin-alpha re-export from the nucleus to the cytoplasm after import substrates (cargos) have been released into the nucleoplasm. In the nucleus binds cooperatively to importin-alpha and to the GTPase Ran in its active GTP-bound form. Docking of this trimeric complex to the nuclear pore complex (NPC) is mediated through binding to nucleoporins. Upon transit of a nuclear export complex into the cytoplasm, disassembling of the complex and hydrolysis of Ran-GTP to Ran-GDP (induced by RANBP1 and RANGAP1, respectively) cause release of the importin-alpha from the export receptor. CSE1L/XPO2 then return to the nuclear compartment and mediate another round of transport. The directionality of nuclear export is thought to be conferred by an asymmetric distribution of the GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus.
Subunit structure	Found in a complex with CSE1L/XPO2, Ran and KPNA2. Binds with high affinity to importin-alpha only in the presence of RanGTP. The complex is dissociated by the combined action of RanBP1 and RanGAP1.
Subcellular location	Cytoplasm. Nucleus. Note= Shuttles between the nucleus and the cytoplasm.
Tissue specificity	Highly expressed in proliferating cells.
Sequence similarities	Belongs to the XPO2/CSE1 family. Contains 1 importin N-terminal domain.

Ontologies

Keywords
Biological process	Protein transport Transport
Cellular component	Cytoplasm Nucleus
Coding sequence diversity	Alternative splicing Polymorphism
PTM	Acetylation
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	apoptosis Ref.1 Traceable author statement. Source: ProtInc cell proliferation Ref.1 Traceable author statement. Source: ProtInc protein import into nucleus, docking Inferred from electronic annotation. Source: InterPro
Cellular component	cytoplasm Ref.6 Traceable author statement. Source: ProtInc nuclear pore Inferred from electronic annotation. Source: InterPro
Molecular function	importin-alpha export receptor activity Ref.6 Traceable author statement. Source: ProtInc
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
TP53	P04637	4	EBI-286709,EBI-366083

Alternative products

This entry describes 3 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: P55060-1)

Also known as: A;

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform 2 (identifier: P55060-2)

The sequence of this isoform differs from the canonical sequence as follows:
     190-195: ATIELC → VWNASW
     196-971: Missing.

Isoform 3 (identifier: P55060-3)

The sequence of this isoform differs from the canonical sequence as follows:
     943-945: VPS → TYF
     946-971: Missing.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 971	971	Exportin-2		PRO_0000117287
Regions
	Domain	29 – 102	74	Importin N-terminal
Amino acid modifications
	Modified residue	1	1	N-acetylmethionine
Natural variations
	Alternative sequence	190 – 195	6	ATIELC → VWNASW in isoform 2.		VSP_001222
	Alternative sequence	196 – 971	776	Missing in isoform 2.		VSP_001223
	Alternative sequence	943 – 945	3	VPS → TYF in isoform 3.		VSP_001224
	Alternative sequence	946 – 971	26	Missing in isoform 3.		VSP_001225
	Natural variant	754	1	I → V: dbSNP rs2229042.		VAR_029327
	Natural variant	842	1	C → F in a colorectal cancer sample; somatic mutation.		VAR_036558
Experimental info
	Sequence conflict	231 – 233	3	FED → WEG in AAC50367. Ref.1
	Sequence conflict	231 – 233	3	FED → WEG in AAC35008. Ref.2
	Sequence conflict	514	1	E → G in AAC50367. Ref.1
	Sequence conflict	514	1	E → G in AAC35008. Ref.2
	Sequence conflict	848	1	K → N in AAC50367. Ref.1
	Sequence conflict	934	1	K → M in AAC50367. Ref.1

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 (A) [UniParc]. Last modified March 29, 2005. Version 3. Checksum: 08E837AB5008EBFD	FASTA	971	110,417
	10 20 30 40 50 60 MELSDANLQT LTEYLKKTLD PDPAIRRPAE KFLESVEGNQ NYPLLLLTLL EKSQDNVIKV 70 80 90 100 110 120 CASVTFKNYI KRNWRIVEDE PNKICEADRV AIKANIVHLM LSSPEQIQKQ LSDAISIIGR 130 140 150 160 170 180 EDFPQKWPDL LTEMVNRFQS GDFHVINGVL RTAHSLFKRY RHEFKSNELW TEIKLVLDAF 190 200 210 220 230 240 ALPLTNLFKA TIELCSTHAN DASALRILFS SLILISKLFY SLNFQDLPEF FEDNMETWMN 250 260 270 280 290 300 NFHTLLTLDN KLLQTDDEEE AGLLELLKSQ ICDNAALYAQ KYDEEFQRYL PRFVTAIWNL 310 320 330 340 350 360 LVTTGQEVKY DLLVSNAIQF LASVCERPHY KNLFEDQNTL TSICEKVIVP NMEFRAADEE 370 380 390 400 410 420 AFEDNSEEYI RRDLEGSDID TRRRAACDLV RGLCKFFEGP VTGIFSGYVN SMLQEYAKNP 430 440 450 460 470 480 SVNWKHKDAA IYLVTSLASK AQTQKHGITQ ANELVNLTEF FVNHILPDLK SANVNEFPVL 490 500 510 520 530 540 KADGIKYIMI FRNQVPKEHL LVSIPLLINH LQAESIVVHT YAAHALERLF TMRGPNNATL 550 560 570 580 590 600 FTAAEIAPFV EILLTNLFKA LTLPGSSENE YIMKAIMRSF SLLQEAIIPY IPTLITQLTQ 610 620 630 640 650 660 KLLAVSKNPS KPHFNHYMFE AICLSIRITC KANPAAVVNF EEALFLVFTE ILQNDVQEFI 670 680 690 700 710 720 PYVFQVMSLL LETHKNDIPS SYMALFPHLL QPVLWERTGN IPALVRLLQA FLERGSNTIA 730 740 750 760 770 780 SAAADKIPGL LGVFQKLIAS KANDHQGFYL LNSIIEHMPP ESVDQYRKQI FILLFQRLQN 790 800 810 820 830 840 SKTTKFIKSF LVFINLYCIK YGALALQEIF DGIQPKMFGM VLEKIIIPEI QKVSGNVEKK 850 860 870 880 890 900 ICAVGITKLL TECPPMMDTE YTKLWTPLLQ SLIGLFELPE DDTIPDEEHF IDIEDTPGYQ 910 920 930 940 950 960 TAFSQLAFAG KKEHDPVGQM VNNPKIHLAQ SLHKLSTACP GRVPSMVSTS LNAEALQYLQ 970 GYLQAASVTL L
	Isoform 2 [UniParc]. Checksum: 94798963277F26F5		195	22,670
	10 20 30 40 50 60 MELSDANLQT LTEYLKKTLD PDPAIRRPAE KFLESVEGNQ NYPLLLLTLL EKSQDNVIKV 70 80 90 100 110 120 CASVTFKNYI KRNWRIVEDE PNKICEADRV AIKANIVHLM LSSPEQIQKQ LSDAISIIGR 130 140 150 160 170 180 EDFPQKWPDL LTEMVNRFQS GDFHVINGVL RTAHSLFKRY RHEFKSNELW TEIKLVLDAF 190 ALPLTNLFKV WNASW
	Isoform 3 [UniParc]. Checksum: 6E2D39436F2ABDD9		945	107,778
	10 20 30 40 50 60 MELSDANLQT LTEYLKKTLD PDPAIRRPAE KFLESVEGNQ NYPLLLLTLL EKSQDNVIKV 70 80 90 100 110 120 CASVTFKNYI KRNWRIVEDE PNKICEADRV AIKANIVHLM LSSPEQIQKQ LSDAISIIGR 130 140 150 160 170 180 EDFPQKWPDL LTEMVNRFQS GDFHVINGVL RTAHSLFKRY RHEFKSNELW TEIKLVLDAF 190 200 210 220 230 240 ALPLTNLFKA TIELCSTHAN DASALRILFS SLILISKLFY SLNFQDLPEF FEDNMETWMN 250 260 270 280 290 300 NFHTLLTLDN KLLQTDDEEE AGLLELLKSQ ICDNAALYAQ KYDEEFQRYL PRFVTAIWNL 310 320 330 340 350 360 LVTTGQEVKY DLLVSNAIQF LASVCERPHY KNLFEDQNTL TSICEKVIVP NMEFRAADEE 370 380 390 400 410 420 AFEDNSEEYI RRDLEGSDID TRRRAACDLV RGLCKFFEGP VTGIFSGYVN SMLQEYAKNP 430 440 450 460 470 480 SVNWKHKDAA IYLVTSLASK AQTQKHGITQ ANELVNLTEF FVNHILPDLK SANVNEFPVL 490 500 510 520 530 540 KADGIKYIMI FRNQVPKEHL LVSIPLLINH LQAESIVVHT YAAHALERLF TMRGPNNATL 550 560 570 580 590 600 FTAAEIAPFV EILLTNLFKA LTLPGSSENE YIMKAIMRSF SLLQEAIIPY IPTLITQLTQ 610 620 630 640 650 660 KLLAVSKNPS KPHFNHYMFE AICLSIRITC KANPAAVVNF EEALFLVFTE ILQNDVQEFI 670 680 690 700 710 720 PYVFQVMSLL LETHKNDIPS SYMALFPHLL QPVLWERTGN IPALVRLLQA FLERGSNTIA 730 740 750 760 770 780 SAAADKIPGL LGVFQKLIAS KANDHQGFYL LNSIIEHMPP ESVDQYRKQI FILLFQRLQN 790 800 810 820 830 840 SKTTKFIKSF LVFINLYCIK YGALALQEIF DGIQPKMFGM VLEKIIIPEI QKVSGNVEKK 850 860 870 880 890 900 ICAVGITKLL TECPPMMDTE YTKLWTPLLQ SLIGLFELPE DDTIPDEEHF IDIEDTPGYQ 910 920 930 940 TAFSQLAFAG KKEHDPVGQM VNNPKIHLAQ SLHKLSTACP GRTYF

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Cloning and characterization of a cellular apoptosis susceptibility gene, the human homologue to the yeast chromosome segregation gene CSE1." Brinkmann U., Brinkmann E., Gallo M., Pastan I. Proc. Natl. Acad. Sci. U.S.A. 92:10427-10431(1995) [PubMed: 7479798] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). Tissue: Placenta.
[2]	"Tissue-specific alternative splicing of the CSE1L/CAS (cellular apoptosis susceptibility) gene." Brinkmann U., Brinkmann E., Bera T.K., Wellmann A., Pastan I. Genomics 58:41-49(1999) [PubMed: 10331944] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORMS 1; 2 AND 3). Tissue: Brain.
[3]	"The DNA sequence and comparative analysis of human chromosome 20." Deloukas P., Matthews L.H., Ashurst J.L., Burton J., Gilbert J.G.R., Jones M., Stavrides G., Almeida J.P., Babbage A.K., Bagguley C.L., Bailey J., Barlow K.F., Bates K.N., Beard L.M., Beare D.M., Beasley O.P., Bird C.P., Blakey S.E. , Bridgeman A.M., Brown A.J., Buck D., Burrill W.D., Butler A.P., Carder C., Carter N.P., Chapman J.C., Clamp M., Clark G., Clark L.N., Clark S.Y., Clee C.M., Clegg S., Cobley V.E., Collier R.E., Connor R.E., Corby N.R., Coulson A., Coville G.J., Deadman R., Dhami P.D., Dunn M., Ellington A.G., Frankland J.A., Fraser A., French L., Garner P., Grafham D.V., Griffiths C., Griffiths M.N.D., Gwilliam R., Hall R.E., Hammond S., Harley J.L., Heath P.D., Ho S., Holden J.L., Howden P.J., Huckle E., Hunt A.R., Hunt S.E., Jekosch K., Johnson C.M., Johnson D., Kay M.P., Kimberley A.M., King A., Knights A., Laird G.K., Lawlor S., Lehvaeslaiho M.H., Leversha M.A., Lloyd C., Lloyd D.M., Lovell J.D., Marsh V.L., Martin S.L., McConnachie L.J., McLay K., McMurray A.A., Milne S.A., Mistry D., Moore M.J.F., Mullikin J.C., Nickerson T., Oliver K., Parker A., Patel R., Pearce T.A.V., Peck A.I., Phillimore B.J.C.T., Prathalingam S.R., Plumb R.W., Ramsay H., Rice C.M., Ross M.T., Scott C.E., Sehra H.K., Shownkeen R., Sims S., Skuce C.D., Smith M.L., Soderlund C., Steward C.A., Sulston J.E., Swann R.M., Sycamore N., Taylor R., Tee L., Thomas D.W., Thorpe A., Tracey A., Tromans A.C., Vaudin M., Wall M., Wallis J.M., Whitehead S.L., Whittaker P., Willey D.L., Williams L., Williams S.A., Wilming L., Wray P.W., Hubbard T., Durbin R.M., Bentley D.R., Beck S., Rogers J. Nature 414:865-871(2001) [PubMed: 11780052] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[4]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1). Tissue: Testis.
[5]	Bienvenut W.V. Submitted (JUN-2005) to UniProtKB Cited for: PROTEIN SEQUENCE OF 1-16; 18-26; 32-67; 76-83; 94-109; 138-151; 166-217; 252-268; 282-288; 293-309; 332-371; 373-382; 396-418; 428-440; 446-481; 560-574; 698-736; 769-777; 789-816; 825-832 AND 913-934, ACETYLATION AT MET-1, MASS SPECTROMETRY. Tissue: B-cell lymphoma.
[6]	"Export of importin-alpha from the nucleus is mediated by a specific nuclear transport factor." Kutay U., Bischoff F.R., Kostka S., Kraft R., Goerlich D. Cell 90:1061-1071(1997) [PubMed: 9323134] [Abstract] Cited for: PROTEIN SEQUENCE OF 356-370, FUNCTION IN PROTEIN NUCLEAR EXPORT, IDENTIFICATION IN A COMPLEX WITH RAN AND KPNA2.
[7]	"Determination of the functional domain organization of the importin alpha nuclear import factor." Herold A., Truant R., Wiegand H., Cullen B.R. J. Cell Biol. 143:309-318(1998) [PubMed: 9786944] [Abstract] Cited for: INTERACTION WITH KPNA2.
[8]	"The consensus coding sequences of human breast and colorectal cancers." Sjoeblom T., Jones S., Wood L.D., Parsons D.W., Lin J., Barber T.D., Mandelker D., Leary R.J., Ptak J., Silliman N., Szabo S., Buckhaults P., Farrell C., Meeh P., Markowitz S.D., Willis J., Dawson D., Willson J.K.V. , Gazdar A.F., Hartigan J., Wu L., Liu C., Parmigiani G., Park B.H., Bachman K.E., Papadopoulos N., Vogelstein B., Kinzler K.W., Velculescu V.E. Science 314:268-274(2006) [PubMed: 16959974] [Abstract] Cited for: VARIANT [LARGE SCALE ANALYSIS] PHE-842.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBLGenBankDDBJ	U33286 mRNA. Translation: AAC50367.1. AF053640 mRNA. Translation: AAC35007.1. AF053641 mRNA. Translation: AAC35008.1. AF053642 mRNA. Translation: AAC35009.1. AF053651 , AF053644, AF053645, AF053646, AF053647, AF053648, AF053649, AF053650 Genomic DNA. Translation: AAC35297.1. AL121903, AL133174 Genomic DNA. Translation: CAI19615.1. AL133174, AL121903 Genomic DNA. Translation: CAI42818.1. BC108309 mRNA. Translation: AAI08310.1. BC109313 mRNA. Translation: AAI09314.1. BC109314 mRNA. Translation: AAI09315.1.
PIR	I39166.
RefSeq	NP_001307.2.
UniGene	Hs.90073
3D structure databases
ModBase	Search...
Protein-protein interaction databases
IntAct	P55060.
PTM databases
PhosphoSite	P55060.
Genome annotation databases
Ensembl	ENSG00000124207. Homo sapiens. [Contig view]
GeneID	1434.
KEGG	hsa:1434.
Organism-specific databases
H-InvDB	HIX0015896.
HGNC	HGNC:2431. CSE1L.
HPA	CAB002140.
MIM	601342. gene.
PharmGKB	PA26933.
GenAtlas	Search...
GeneCards	Search...
Phylogenomic databases
HOVERGEN	P55060.
Gene expression databases
ArrayExpress	P55060.
CleanEx	HS_CSE1L.
GermOnline	ENSG00000124207. Homo sapiens.
Family and domain databases
InterPro	IPR011989. ARM-like. IPR005043. CAS_CSE1_C. IPR013713. Exportin_Cse1-like. IPR001494. Importin-b_N. [Graphical view]
Gene3D	G3DSA:1.25.10.10. ARM-like. 1 hit.
Pfam	PF03378. CAS_CSE1. 1 hit. PF08506. Cse1. 1 hit. PF03810. IBN_N. 1 hit. [Graphical view]
PROSITE	PS50166. IMPORTIN_B_NT. 1 hit. [Graphical view]
ProtoNet	Search...
Other Resources
NextBio	5853.
SOURCE	Search...

Entry information

Entry name

XPO2_HUMAN

Accession

Primary (citable) accession number: P55060
Secondary accession number(s): O75432 , Q32M40, Q9H5B7, Q9NTS0, Q9UP98, Q9UP99, Q9UPA0

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1996
Last sequence update:	March 29, 2005
Last modified:	November 25, 2008
This is version 78 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)