O97366 · PPAF1_HOLDI

Function

function

Serine endopeptidase which, by cleaving prophenoloxidase PPO1 and PPO2, is required for the activation of the prophenoloxidase cascade probably following the recognition of pathogen-derived products.

Caution

It is not clear if the light chain is degraded after cleavage.

Activity regulation

Protein stability and endopeptidase activity are calcium dependent (PubMed:17287215).
First cleavage on prophenoloxidase PPO1 and PPO2 is not dependent on calcium; however, cleavage of PPO1 and PPO2 to their active forms is dependent on calcium and on the presence of PPAF2 and PPAF3 (PubMed:12185078).
Cleavage of PPAF2 is inhibited by calcium (PubMed:11012672, PubMed:12185078).
Inhibited by ethylenediaminetetraacetic acid (EDTA), p-nitrophenyl-p'-guanido-benzoate, diisopropylphosphorofluoridate (iPr2PF) and p-(Amidinophenyl)methanesulfonyl fluoride (p-APMSF) (PubMed:17287215, PubMed:9652393).

Features

Showing features for site, active site, binding site.

TypeIDPosition(s)Description
Site109-110Cleavage
Active site155Charge relay system
Binding site175Ca2+ (UniProtKB | ChEBI)
Binding site177Ca2+ (UniProtKB | ChEBI)
Binding site180Ca2+ (UniProtKB | ChEBI)
Binding site183Ca2+ (UniProtKB | ChEBI)
Active site220Charge relay system
Active site315Charge relay system

GO annotations

AspectTerm
Cellular Componentextracellular space
Molecular Functioncalcium ion binding
Molecular Functionendopeptidase activity
Molecular Functionpeptidase activity
Molecular Functionserine-type endopeptidase activity
Biological Processinnate immune response
Biological Processproteolysis

Keywords

Enzyme and pathway databases

Protein family/group databases

Names & Taxonomy

Protein names

Gene names

    • Name
      PPAF1
    • Synonyms
      PPAF-I

Organism names

  • Taxonomic identifier
  • Taxonomic lineage
    Eukaryota > Metazoa > Ecdysozoa > Arthropoda > Hexapoda > Insecta > Pterygota > Neoptera > Endopterygota > Coleoptera > Polyphaga > Scarabaeiformia > Scarabaeidae > Melolonthinae > Holotrichia

Accessions

  • Primary accession
    O97366

Subcellular Location

Secreted
Note: Secreted in the hemolymph.

Keywords

PTM/Processing

Features

Showing features for signal, chain, disulfide bond, glycosylation.

TypeIDPosition(s)Description
Signal1-23
ChainPRO_500416079024-109Phenoloxidase-activating factor 1 light chain
Disulfide bond25↔73
Disulfide bond35↔64
Disulfide bond41↔74
Disulfide bond101↔240Interchain (between light and heavy chains)
ChainPRO_0000443316110-365Phenoloxidase-activating factor 1 heavy chain
Glycosylation131N-linked (GlcNAc...) asparagine
Disulfide bond140↔156
Disulfide bond184↔191
Disulfide bond284↔301
Disulfide bond311↔340

Post-translational modification

Cleaved following the recognition of pathogen-derived products, probably by a lysyl endopeptidase.

Keywords

PTM databases

Expression

Developmental stage

Expressed in larva (at protein level).

Interaction

Subunit

In the active form, heterodimer of a light chain and a heavy chain; disulfide-linked (Probable).

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain24-74Clip
Domain110-364Peptidase S1

Domain

The clip domain consists of 35-55 residues which are 'knitted' together usually by 3 conserved disulfide bonds forming a clip-like compact structure (By similarity).
The clip domain is necessary for regulating the zymogen activation (PubMed:16362048).

Sequence similarities

Belongs to the peptidase S1 family. CLIP subfamily.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.
  • Length
    365
  • Mass (Da)
    40,195
  • Last updated
    1999-05-01 v1
  • Checksum
    EC69F6093923F4C5
MKQVHFFILWFFVLNLYSIKAQAGCRTPNGENARCVPINNCKILYDSVLTSDPEVIRFLRASQCGYNGQPLVCCGSSASYQPPPTSASIRNRRPELLPNDCGYQVEADKILNGDDTVPEEFPWTAMIGYKNSSNFEQFACGGSLINNRYIVTAAHCVAGRVLRVVGALNKVRLGEWNTATDPDCYGAVRVCVPDKPIDLGIEETIQHPDYVDGSKDRYHDIALIRLNRQVEFTNYIRPVCLPQPNEEVQVGQRLTVVGWGRTETGQYSTIKQKLAVPVVHAEQCAKTFGAAGVRVRSSQLCAGGEKAKDSCGGDSGGPLLAERANQQFFLEGLVSFGATCGTEGWPGIYTKVGKYRDWIEGNIRP

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AB013088
EMBL· GenBank· DDBJ
BAA34642.1
EMBL· GenBank· DDBJ
mRNA

Similar Proteins

Disclaimer

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