Reviewed, UniProtKB/Swiss-Prot P14091 (CATE_HUMAN)

Names and origin

Protein names

Recommended name:
    Cathepsin E
    EC=3.4.23.34

Gene names

Name:

CTSE

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	401 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	May have a role in immune function. Probably involved in the processing of antigenic peptides during MHC class II-mediated antigen presentation. May play a role in activation-induced lymphocyte depletion in the thymus, and in neuronal degeneration and glial cell activation in the brain.
Catalytic activity	Similar to cathepsin D, but slightly broader specificity.
Subunit structure	Homodimer; disulfide-linked.
Subcellular location	Endosome. Note= The proenzyme is localized to the endoplasmic reticulum and Golgi apparatus, while the mature enzyme is localized to the endosome.
Tissue specificity	Expressed abundantly in the stomach, the Clara cells of the lung and activated B-lymphocytes, and at lower levels in lymph nodes, skin and spleen. Not expressed in resting B-lymphocytes.
Post-translational modification	Glycosylated. The proenzyme contains a high mannose-type oligosaccharide, while the mature enzyme contains a complex-type oligosaccharide.
Sequence similarities	Belongs to the peptidase A1 family.

Ontologies

Keywords
Cellular component	Endosome
Coding sequence diversity	Alternative splicing Polymorphism
Domain	Signal
Molecular function	Aspartyl protease Hydrolase Protease
PTM	Glycoprotein Pyrrolidone carboxylic acid Zymogen
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Uncategorized	cathepsin E activity Ref.7 Inferred from direct assay. Source: UniProtKB
Biological process	antigen processing and presentation of exogenous peptide antigen via MHC class II Ref.8 Inferred from direct assay. Source: UniProtKB digestion Ref.1 Traceable author statement. Source: ProtInc
Cellular component	endosome Ref.3 Inferred from direct assay. Source: UniProtKB
Complete GO annotation...

Alternative products

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

Isoform 3 (identifier: P14091-3)

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 1 (identifier: P14091-1)

The sequence of this isoform differs from the canonical sequence as follows:
     155-159: Missing.

Isoform 2 (identifier: P14091-2)

The sequence of this isoform differs from the canonical sequence as follows:
     155-159: Missing.
     268-368: IQVGGTVMFC...GFQGLDIHPP → MLWSVPTLTS...CVCACLSDRP
     369-401: Missing.

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Molecule processing

Signal peptide

1 – 17

17

Propeptide

18 – 53

36

Activation peptide

Chain

54 – 401

348

Cathepsin E

Sites

Active site

96

1

By similarity

Active site

286

1

By similarity

Amino acid modifications

Modified residue

18

1

Pyrrolidone carboxylic acid

Glycosylation

90

1

N-linked (GlcNAc...)

Disulfide bond

60

Interchain

Disulfide bond

109 ↔ 114

By similarity

Disulfide bond

277 ↔ 281

By similarity

Disulfide bond

319 ↔ 356

By similarity

Natural variations

Alternative sequence

155 – 159

5

Missing in isoform 1 and isoform 2.

Alternative sequence

268 – 368

101

IQVGG…DIHPP → MLWSVPTLTSCRMSPSPLTE SPIPSAQLPTPYWTSWMECS SAAVAFKDLTSTLQLGPSGS WGMSSFDSFTQSLTVGITVW DWPQQSPKEGPCVCACLSDR P in isoform 2.

Alternative sequence

369 – 401

33

Missing in isoform 2.

Natural variant

329

1

T → I: dbSNP rs6503.

Experimental info

Mutagenesis

60

1

C → A: Abolishes homodimerization

Secondary structure

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401

Helix Strand Turn

Details...

Beta strand

22 – 28

7

Helix

32 – 39

8

Helix

42 – 48

7

Helix

54 – 57

4

Helix

59 – 61

3

Helix

71 – 73

3

Beta strand

74 – 76

3

Beta strand

79 – 84

6

Turn

85 – 88

4

Beta strand

89 – 96

8

Beta strand

102 – 106

5

Helix

112 – 114

3

Helix

122 – 124

3

Beta strand

134 – 141

8

Beta strand

143 – 160

18

Beta strand

163 – 173

11

Helix

179 – 183

5

Beta strand

187 – 191

5

Helix

195 – 197

3

Helix

199 – 201

3

Helix

205 – 211

7

Beta strand

216 – 223

8

Beta strand

235 – 238

4

Helix

243 – 245

3

Beta strand

251 – 254

4

Turn

258 – 261

4

Beta strand

262 – 270

9

Beta strand

273 – 276

4

Beta strand

281 – 285

5

Beta strand

290 – 294

5

Helix

296 – 306

11

Beta strand

312 – 317

6

Helix

319 – 324

6

Beta strand

328 – 332

5

Beta strand

335 – 339

5

Turn

341 – 343

3

Beta strand

344 – 346

3

Beta strand

356 – 362

7

Turn

367 – 369

3

Beta strand

373 – 375

3

Helix

377 – 382

6

Beta strand

383 – 388

6

Turn

389 – 392

4

Beta strand

393 – 399

7

Sequences

	Sequence		Length	Mass (Da)
	Isoform 3 [UniParc]. Last modified March 29, 2004. Version 2. Checksum: 46A2BA35266032CB	FASTA	401	43,312
	10 20 30 40 50 60 MKTLLLLLLV LLELGEAQGS LHRVPLRRHP SLKKKLRARS QLSEFWKSHN LDMIQFTESC 70 80 90 100 110 120 SMDQSAKEPL INYLDMEYFG TISIGSPPQN FTVIFDTGSS NLWVPSVYCT SPACKTHSRF 130 140 150 160 170 180 QPSQSSTYSQ PGQSFSIQYG TGSLSGIIGA DQVSAFATQV EGLTVVGQQF GESVTEPGQT 190 200 210 220 230 240 FVDAEFDGIL GLGYPSLAVG GVTPVFDNMM AQNLVDLPMF SVYMSSNPEG GAGSELIFGG 250 260 270 280 290 300 YDHSHFSGSL NWVPVTKQAY WQIALDNIQV GGTVMFCSEG CQAIVDTGTS LITGPSDKIK 310 320 330 340 350 360 QLQNAIGAAP VDGEYAVECA NLNVMPDVTF TINGVPYTLS PTAYTLLDFV DGMQFCSSGF 370 380 390 400 QGLDIHPPAG PLWILGDVFI RQFYSVFDRG NNRVGLAPAV P
	Isoform 1 [UniParc]. Checksum: 40B643C5FB01521E		396	42,794
	10 20 30 40 50 60 MKTLLLLLLV LLELGEAQGS LHRVPLRRHP SLKKKLRARS QLSEFWKSHN LDMIQFTESC 70 80 90 100 110 120 SMDQSAKEPL INYLDMEYFG TISIGSPPQN FTVIFDTGSS NLWVPSVYCT SPACKTHSRF 130 140 150 160 170 180 QPSQSSTYSQ PGQSFSIQYG TGSLSGIIGA DQVSVEGLTV VGQQFGESVT EPGQTFVDAE 190 200 210 220 230 240 FDGILGLGYP SLAVGGVTPV FDNMMAQNLV DLPMFSVYMS SNPEGGAGSE LIFGGYDHSH 250 260 270 280 290 300 FSGSLNWVPV TKQAYWQIAL DNIQVGGTVM FCSEGCQAIV DTGTSLITGP SDKIKQLQNA 310 320 330 340 350 360 IGAAPVDGEY AVECANLNVM PDVTFTINGV PYTLSPTAYT LLDFVDGMQF CSSGFQGLDI 370 380 390 HPPAGPLWIL GDVFIRQFYS VFDRGNNRVG LAPAVP
	Isoform 2 [UniParc]. Checksum: 4443819D6393C1FC		363	39,553
	10 20 30 40 50 60 MKTLLLLLLV LLELGEAQGS LHRVPLRRHP SLKKKLRARS QLSEFWKSHN LDMIQFTESC 70 80 90 100 110 120 SMDQSAKEPL INYLDMEYFG TISIGSPPQN FTVIFDTGSS NLWVPSVYCT SPACKTHSRF 130 140 150 160 170 180 QPSQSSTYSQ PGQSFSIQYG TGSLSGIIGA DQVSVEGLTV VGQQFGESVT EPGQTFVDAE 190 200 210 220 230 240 FDGILGLGYP SLAVGGVTPV FDNMMAQNLV DLPMFSVYMS SNPEGGAGSE LIFGGYDHSH 250 260 270 280 290 300 FSGSLNWVPV TKQAYWQIAL DNMLWSVPTL TSCRMSPSPL TESPIPSAQL PTPYWTSWME 310 320 330 340 350 360 CSSAAVAFKD LTSTLQLGPS GSWGMSSFDS FTQSLTVGIT VWDWPQQSPK EGPCVCACLS DRP

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Human gastric cathepsin E. Predicted sequence, localization to chromosome 1, and sequence homology with other aspartic proteinases." Azuma T., Pals G., Mohandas T.K., Couvreur J.M., Taggart R.T. J. Biol. Chem. 264:16748-16753(1989) [PubMed: 2674141] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1 AND 2). Tissue: Gastric mucosa.
[2]	"Human gastric cathepsin E gene. Multiple transcripts result from alternative polyadenylation of the primary transcripts of a single gene locus at 1q31-q32." Azuma T., Liu W.G., Vander Laan D.J., Bowcock A.M., Taggart R.T. J. Biol. Chem. 267:1609-1614(1992) [PubMed: 1370478] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ISOFORM 1), TISSUE SPECIFICITY.
[3]	"Subcellular localization and targeting of cathepsin E." Finley E.M., Kornfeld S. J. Biol. Chem. 269:31259-31266(1994) [PubMed: 7983070] [Abstract] Cited for: NUCLEOTIDE SEQUENCE (ISOFORMS 1 AND 3), SUBCELLULAR LOCATION, GLYCOSYLATION. Tissue: Intestine.
[4]	"An alternatively spliced variant of cathepsin E in human gastric adenocarcinoma cells." Tatnell P.J., Cook M., Kay J. Biochim. Biophys. Acta 1625:203-206(2003) [PubMed: 12531480] [Abstract] Cited for: NUCLEOTIDE SEQUENCE (ISOFORMS 1 AND 2). Tissue: Gastric adenocarcinoma.
[5]	"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: Brain.
[6]	"Structural evidence for two isozymic forms and the carbohydrate attachment site of human gastric cathepsin E." Athauda S.B.P., Matsuzaki O., Kgeyama T., Takahashi K. Biochem. Biophys. Res. Commun. 168:878-885(1990) [PubMed: 2334440] [Abstract] Cited for: PROTEIN SEQUENCE OF 54-68; 77-95; 141-154; 280-290 AND 394-401, GLYCOSYLATION. Tissue: Gastric mucosa.
[7]	"Monomeric human cathepsin E." Fowler S.D., Kay J., Dunn B.M., Tatnell P.J. FEBS Lett. 366:72-74(1995) [PubMed: 7789521] [Abstract] Cited for: CATALYTIC ACTIVITY, SUBUNIT, DISULFIDE BONDS, MUTAGENESIS OF CYS-60.
[8]	"Regulation of cathepsin E expression during human B cell differentiation in vitro." Sealy L., Mota F., Rayment N., Tatnell P.J., Kay J., Chain B. Eur. J. Immunol. 26:1838-1843(1996) [PubMed: 8765029] [Abstract] Cited for: FUNCTION, CATALYTIC ACTIVITY, TISSUE SPECIFICITY.
[9]	"Regulation of human and mouse procathepsin E gene expression." Cook M., Caswell R.C., Richards R.J., Kay J., Tatnell P.J. Eur. J. Biochem. 268:2658-2668(2001) [PubMed: 11322887] [Abstract] Cited for: TISSUE SPECIFICITY.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBLGenBankDDBJ	M84424 , M84413, M84417, M84418, M84419, M84420, M84421, M84422 Genomic DNA. Translation: AAA52300.1. J05036 mRNA. Translation: AAA52130.1. AJ250716 mRNA. Translation: CAB82849.1. AJ250717 mRNA. Translation: CAB82850.1. BC042537 mRNA. Translation: AAH42537.1.
PIR<