P81397 (RHCA_CALRH) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Rhodocetin subunit alpha
Organism	Calloselasma rhodostoma (Malayan pit viper) (Agkistrodon rhodostoma)
Taxonomic identifier	8717 [NCBI]
Taxonomic lineage	Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Lepidosauria › Squamata › Scleroglossa › Serpentes › Colubroidea › Viperidae › Crotalinae › Calloselasma

Protein attributes

Sequence length	133 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	A potent inhibitor of collagen-induced platelet aggregation. Individually, neither subunit inhibits platelet aggregation. Both subunits are essential. Ref.1
Subunit structure	Heterodimer of subunits alpha and beta; held together by noncovalent interactions rather than by intersubunit disulfide bridges. Ref.1
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland.
Sequence similarities	Contains 1 C-type lectin domain.
Mass spectrometry	Molecular mass is 15955.90±1.44 Da from positions 1 - 133. Determined by ESI. Ref.1

Ontologies

Keywords
Cellular component	Secreted
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

Chain

1 – 133

133

Rhodocetin subunit alpha

PRO_0000046706

Regions

Domain

1 – 129

129

C-type lectin

Amino acid modifications

Disulfide bond

2 ↔ 13

Ref.2

Disulfide bond

30 ↔ 127

Ref.2

Disulfide bond

102 ↔ 119

Ref.2

Secondary structure

1

.

.

.

.

.

.

.

.

.

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.

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.

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.

.

.

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.

.

.

133

Helix Strand Turn

Details...

Beta strand

10 – 21

12

Helix

23 – 31

9

Beta strand

33 – 35

3

Helix

45 – 58

14

Turn

59 – 61

3

Beta strand

64 – 73

10

Beta strand

79 – 83

5

Beta strand

94 – 96

3

Beta strand

100 – 111

12

Beta strand

113 – 117

5

Beta strand

123 – 130

8

Sequences

	Sequence		Length	Mass (Da)
	P81397 [UniParc]. Last modified July 15, 1998. Version 1. Checksum: 386EAC519DFC674D	FASTA	133	15,962
	10 20 30 40 50 60 DCPDGWSSTK SYCYRPFKEK KTWEEAERFC TEQEKEAHLV SMENRLEAVF VDMVMENNFE 70 80 90 100 110 120 NKIYRSWIGL KIENKGQRSN LEWSDGSSIS YENLYEPYME KCFLMDHQSG LPKWHTADCE 130 EKNVFMCKFQ LPR

References

[1]	"Rhodocetin, a novel platelet aggregation inhibitor from the venom of Calloselasma rhodostoma (Malayan pit viper): synergistic and noncovalent interaction between its subunits." Wang R., Kini R.M., Chung M.C.M. Biochemistry 38:7584-7593(1999) [PubMed: 10360956] [Abstract] Cited for: PROTEIN SEQUENCE, FUNCTION, SUBUNIT, MASS SPECTROMETRY. Tissue: Venom.
[2]	"Structure of rhodocetin reveals noncovalently bound heterodimer interface." Paaventhan P., Kong C., Joseph J.S., Chung M.C., Kolatkar P.R. Protein Sci. 14:169-175(2005) [PubMed: 15576563] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS) IN COMPLEX WITH RHCB, DISULFIDE BONDS.
+	Additional computationally mapped references.

Cross-references

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1SB2	X-ray	1.90	A	1-133	[»]
3GPR	X-ray	3.20	A	1-133	[»]

ProteinModelPortal

P81397.

SMR

P81397. Positions 1-132.

ModBase

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Protocols and materials databases

StructuralBiologyKnowledgebase

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Phylogenomic databases

HOVERGEN

HBG004151.

Family and domain databases

InterPro

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

Gene3D

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

Pfam

PF00059. Lectin_C. 1 hit.
[Graphical view]

SMART

SM00034. CLECT. 1 hit.
[Graphical view]

SUPFAM

SSF56436. C-type_lectin_fold. 1 hit.

PROSITE

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

ProtoNet

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Entry information

Entry name

RHCA_CALRH

Accession

Primary (citable) accession number: P81397

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 15, 1998
Last sequence update:	July 15, 1998
Last modified:	January 25, 2012
This is version 60 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program