PA2HA_TRIPE
ID PA2HA_TRIPE Reviewed; 138 AA.
AC Q2YHJ9;
DT 05-SEP-2012, integrated into UniProtKB/Swiss-Prot.
DT 20-DEC-2005, sequence version 1.
DT 25-MAY-2022, entry version 66.
DE RecName: Full=Basic phospholipase A2 homolog Tpu-K49a {ECO:0000303|PubMed:15955061};
DE Short=svPLA2 homolog;
DE Flags: Precursor;
OS Trimeresurus puniceus (Flat-nosed pitviper).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC Serpentes; Colubroidea; Viperidae; Crotalinae; Trimeresurus.
OX NCBI_TaxID=197218;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 17-39, FUNCTION, SUBUNIT,
RP MASS SPECTROMETRY, AND SUBCELLULAR LOCATION.
RC TISSUE=Venom, and Venom gland;
RX PubMed=15955061; DOI=10.1111/j.1742-4658.2005.04715.x;
RA Wang Y.-M., Peng H.-F., Tsai I.-H.;
RT "Unusual venom phospholipases A2 of two primitive tree vipers Trimeresurus
RT puniceus and Trimeresurus borneensis.";
RL FEBS J. 272:3015-3025(2005).
CC -!- FUNCTION: Snake venom phospholipase A2 homolog that lacks catalytic
CC activity (PubMed:15955061). Induces local edema a few hours after
CC injection in the hind foot (PubMed:15955061). Is myotoxic (By
CC similarity). A model of myotoxic mechanism has been proposed: an apo
CC Lys49-PLA2 is activated by the entrance of a hydrophobic molecule (e.g.
CC fatty acid) at the hydrophobic channel of the protein leading to a
CC reorientation of a monomer (By similarity). This reorientation causes a
CC transition between 'inactive' to 'active' states, causing alignment of
CC C-terminal and membrane-docking sites (MDoS) side-by-side and putting
CC the membrane-disruption sites (MDiS) in the same plane, exposed to
CC solvent and in a symmetric position for both monomers (By similarity).
CC The MDoS region stabilizes the toxin on membrane by the interaction of
CC charged residues with phospholipid head groups (By similarity).
CC Subsequently, the MDiS region destabilizes the membrane with
CC penetration of hydrophobic residues (By similarity). This insertion
CC causes a disorganization of the membrane, allowing an uncontrolled
CC influx of ions (i.e. calcium and sodium), and eventually triggering
CC irreversible intracellular alterations and cell death (By similarity).
CC {ECO:0000250|UniProtKB:I6L8L6, ECO:0000269|PubMed:15955061}.
CC -!- SUBUNIT: Monomer. {ECO:0000269|PubMed:15955061}.
CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:15955061}.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC {ECO:0000305|PubMed:15955061}.
CC -!- MASS SPECTROMETRY: Mass=14221.5; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:15955061};
CC -!- SIMILARITY: Belongs to the phospholipase A2 family. Group II subfamily.
CC K49 sub-subfamily. {ECO:0000305}.
CC -!- CAUTION: Does not bind calcium as one of the calcium-binding sites is
CC lost (Asp->Lys in position 64, which corresponds to 'Lys-49' in the
CC current nomenclature). {ECO:0000305}.
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DR EMBL; AY355171; AAR14165.1; -; mRNA.
DR AlphaFoldDB; Q2YHJ9; -.
DR SMR; Q2YHJ9; -.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0005509; F:calcium ion binding; IEA:InterPro.
DR GO; GO:0004623; F:phospholipase A2 activity; IEA:InterPro.
DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR GO; GO:0050482; P:arachidonic acid secretion; IEA:InterPro.
DR GO; GO:0016042; P:lipid catabolic process; IEA:InterPro.
DR GO; GO:0006644; P:phospholipid metabolic process; IEA:InterPro.
DR CDD; cd00125; PLA2c; 1.
DR Gene3D; 1.20.90.10; -; 1.
DR InterPro; IPR001211; PLipase_A2.
DR InterPro; IPR033112; PLipase_A2_Asp_AS.
DR InterPro; IPR016090; PLipase_A2_dom.
DR InterPro; IPR036444; PLipase_A2_dom_sf.
DR InterPro; IPR033113; PLipase_A2_His_AS.
DR PANTHER; PTHR11716; PTHR11716; 1.
DR Pfam; PF00068; Phospholip_A2_1; 1.
DR PRINTS; PR00389; PHPHLIPASEA2.
DR SMART; SM00085; PA2c; 1.
DR SUPFAM; SSF48619; SSF48619; 1.
DR PROSITE; PS00119; PA2_ASP; 1.
DR PROSITE; PS00118; PA2_HIS; 1.
PE 1: Evidence at protein level;
KW Direct protein sequencing; Disulfide bond; Hemostasis impairing toxin;
KW Myotoxin; Secreted; Signal; Toxin.
FT SIGNAL 1..16
FT /evidence="ECO:0000269|PubMed:15955061"
FT CHAIN 17..138
FT /note="Basic phospholipase A2 homolog Tpu-K49a"
FT /id="PRO_0000419062"
FT REGION 121..133
FT /note="Important for membrane-damaging activities in
FT eukaryotes and bacteria; heparin-binding"
FT /evidence="ECO:0000250|UniProtKB:P24605"
FT SITE 121
FT /note="Important residue of the cationic membrane-docking
FT site (MDoS)"
FT /evidence="ECO:0000250|UniProtKB:I6L8L6"
FT SITE 124
FT /note="Important residue of the cationic membrane-docking
FT site (MDoS)"
FT /evidence="ECO:0000250|UniProtKB:I6L8L6"
FT SITE 128
FT /note="Cationic membrane-docking site (MDoS)"
FT /evidence="ECO:0000250|UniProtKB:I6L8L6"
FT SITE 130
FT /note="Hydrophobic membrane-disruption site (MDiS)"
FT /evidence="ECO:0000250|UniProtKB:I6L8L6"
FT SITE 133
FT /note="Cationic membrane-docking site (MDoS)"
FT /evidence="ECO:0000250|UniProtKB:I6L8L6"
FT DISULFID 42..131
FT /evidence="ECO:0000250|UniProtKB:Q90249"
FT DISULFID 44..60
FT /evidence="ECO:0000250|UniProtKB:Q90249"
FT DISULFID 59..111
FT /evidence="ECO:0000250|UniProtKB:Q90249"
FT DISULFID 65..138
FT /evidence="ECO:0000250|UniProtKB:Q90249"
FT DISULFID 66..104
FT /evidence="ECO:0000250|UniProtKB:Q90249"
FT DISULFID 91..102
FT /evidence="ECO:0000250|UniProtKB:Q90249"
SQ SEQUENCE 138 AA; 16008 MW; 2F13F2633A621E0E CRC64;
MRTLWIMAVL LVGVEGSVIQ LGKMILQETG KNPVKYYGAY GCNCGPLGRR KPLDATDRCC
YMHKCCYKKL TDSNPIKDRY SYSWENKAIV CKEKNPRLKE MCECDKAVAI CFRENMRTYN
KKERINTKIF CKKTPEPC
