Procyclin

Procyclins also known as procyclic acidic repetitive proteins or PARP^[1] are proteins developed in the surface coating of Trypanosoma brucei parasites while in their tsetse fly vector.^[2] The cell surface of the bloodstream form features a dense coat of variable surface glycoproteins (VSGs) which is replaced by an equally dense coat of procyclins when the parasite differentiates into the procylic form in the tsetse fly midgut.

Procyclic acidic repetitive
Identifiers
Symbol	?
Pfam	PF05887
InterPro	IPR008882
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

EP1 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	Tb10.6k15.0020
Entrez	3661797
RefSeq (mRNA)	XM_818154.1
RefSeq (Prot)	XP_823247.1
UniProt	Q389V1
Other data
Chromosome	10: 2.48 - 2.48 Mb
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Surface protein EP1-2 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	EP1-2
UniProt	Q7KG35
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EP2 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	Tb10.6k15.0030
Entrez	3661534
RefSeq (mRNA)	XM_818153.1
RefSeq (Prot)	XP_823246.1
UniProt	Q389V2
Other data
Chromosome	10: 2.48 - 2.48 Mb
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Surface protein EP2-1 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	EP2-1
UniProt	Q95PJ2
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Procyclin EP3
Identifiers
Organism	Trypanosoma brucei
Symbol	EP3
UniProt	Q86MA3
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EP3-2 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	Tb927.6.520
Entrez	3657688
RefSeq (mRNA)	XM_840082.1
RefSeq (Prot)	XP_845175.1
UniProt	Q581F6
Other data
Chromosome	6: 0.23 - 0.23 Mb
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Surface protein EP3-3 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	EP3-3
UniProt	Q95NW2
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Surface protein EP3-4 procyclin
Identifiers
Organism	Trypanosoma brucei
Symbol	EP3-4
UniProt	Q95PJ3
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GPEET2 procyclin precursor
Identifiers
Organism	Trypanosoma brucei
Symbol	Tb927.6.510, Tb06.28F21.90
Entrez	3657686
RefSeq (mRNA)	XM_840081.1
RefSeq (Prot)	XP_845174.1
UniProt	Q581F9
Other data
Chromosome	6: 0.23 - 0.23 Mb
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There are six or seven procyclin genes that encode unusual proteins with extensive tandem repeat units of glutamic acid (E) and proline (P), referred to as EP repeats (EP1, EP1-2, EP2, EP2-1, EP3, EP3-2, EP3-4), and two genes that encode proteins with internal pentapeptide GPEET repeats (GPEET2).^[3]

EP1 is a 141 amino acids protein and EP2 is a 129 AA protein. Both proteins have their coding genes situated on chromosome 10. GPEET2 is a 114 AA protein and EP3-2 is 123 AA protein with genes situated on chromosome 6.

See also

• Coat protein (disambiguation)