Reviewed, UniProtKB/Swiss-Prot Q7T2Q1 (EM16A_ECHML)

Names and origin

Protein names	Recommended name:     EMS16 subunit A       Short name=EMS16A
Organism	Echis multisquamatus (Central Asian sand viper)
Taxonomic identifier	93050 [NCBI]
Taxonomic lineage	Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Lepidosauria › Squamata › Scleroglossa › Serpentes › Colubroidea › Viperidae › Viperinae › Echis

Protein attributes

Sequence length	157 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	EMS16 is a potent and selective inhibitor of alpha-2/beta-1 (ITGA2/ITGB1) integrin. Binds specifically to the I domain of the alpha-2 subunit, in a metal ion-independent fashion.
Subunit structure	Heterodimer of subunits A and B; disulfide-linked. Ref.3
Subcellular location	Secreted.
Sequence similarities	Contains 1 C-type lectin domain.

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Ligand	Lectin
PTM	Disulfide bond
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Cellular component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	sugar binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 23

23

Ref.1 Ref.2

Chain

24 – 157

134

EMS16 subunit A

PRO_0000318802

Regions

Domain

34 – 153

120

C-type lectin

Amino acid modifications

Disulfide bond

27 ↔ 38

Ref.3

Disulfide bond

55 ↔ 152

Ref.3

Disulfide bond

104

Interchain (with C-100 in subunit B) Ref.3

Disulfide bond

127 ↔ 144

Ref.3

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

157

Helix Strand Turn

Details...

Beta strand

32 – 34

3

Beta strand

37 – 46

10

Helix

48 – 58

11

Helix

70 – 79

10

Helix

81 – 85

5

Beta strand

90 – 97

8

Beta strand

100 – 102

3

Beta strand

127 – 131

5

Helix

132 – 134

3

Beta strand

138 – 142

5

Beta strand

148 – 155

8

Sequences

	Sequence		Length	Mass (Da)
	Q7T2Q1-1 [UniParc]. Last modified October 1, 2003. Version 1. Checksum: F0D9638C6D622AB3	FASTA	157	18,214
	10 20 30 40 50 60 MGRFISVSFG LLVVFLSLSG TGADFDCPSD WTAYDQHCYL AIGEPQNWYE AERFCTEQAK 70 80 90 100 110 120 DGHLVSIQSR EEGNFVAQLV SGFMHRSEIY VWIGLRDRRE EQQCNPEWND GSKIIYVNWK 130 140 150 EGESKMCQGL TKWTNFHDWN NINCEDLYPF VCKFSAV

References

[1]	"Characterization and preliminary crystallographic studies of EMS16, an antagonist of collagen receptor (GPIa/IIa) from the venom of Echis multisquamatus." Okuda D., Horii K., Mizuno H., Morita T. J. Biochem. 134:19-23(2003) [PubMed: 12944366] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 24-44.
[2]	"Isolation and characterization of EMS16, a C-lectin type protein from Echis multisquamatus venom, a potent and selective inhibitor of the alpha2beta1 integrin." Marcinkiewicz C., Lobb R.R., Marcinkiewicz M.M., Daniel J.L., Smith J.B., Dangelmaier C., Weinreb P.H., Beacham D.A., Niewiarowski S. Biochemistry 39:9859-9867(2000) [PubMed: 10933804] [Abstract] Cited for: PROTEIN SEQUENCE OF 24-82.
[3]	"Structural characterization of EMS16, an antagonist of collagen receptor (GPIa/IIa) from the venom of Echis multisquamatus." Horii K., Okuda D., Morita T., Mizuno H. Biochemistry 42:12497-12502(2003) [PubMed: 14580195] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS) OF 24-157 IN COMPLEX WITH EMS16B, DISULFIDE BONDS.
[4]	"Crystal structure of EMS16 in complex with the integrin alpha2-I domain." Horii K., Okuda D., Morita T., Mizuno H. J. Mol. Biol. 341:519-527(2004) [PubMed: 15276841] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS) OF 24-157 IN COMPLEX WITH EMS16B AND ITGA2.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

AB098253 mRNA. Translation: BAC77706.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1UKM	X-ray	1.90	A	24-157	[»]
1V7P	X-ray	1.90	A	24-157	[»]

ModBase

Search...

Phylogenomic databases

HOVERGEN

Q7T2Q1.

Family and domain databases

InterPro

IPR001304. C-type_lectin.
IPR016186. C-type_lectin-like.
IPR016187. C-type_lectin_fold.
IPR003990. Pancreatis_ac.
[Graphical view]

Gene3D

G3DSA:3.10.100.10. C-type_lectin-like. 1 hit.

Pfam

PF00059. Lectin_C. 1 hit.
[Graphical view]

PRINTS

PR01504. PNCREATITSAP.

SMART

SM00034. CLECT. 1 hit.
[Graphical view]

PROSITE

PS00615. C_TYPE_LECTIN_1. False negative.
PS50041. C_TYPE_LECTIN_2. 1 hit.
[Graphical view]

ProtoNet

Search...

Entry information

Entry name

EM16A_ECHML

Accession

Primary (citable) accession number: Q7T2Q1

Entry history

Integrated into UniProtKB/Swiss-Prot:	February 26, 2008
Last sequence update:	October 1, 2003
Last modified:	November 24, 2009
This is version 29 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)