module: dmel_signal_peptidase_complex
title: Signal peptidase complex in Drosophila melanogaster
label: Signal peptidase complex
module_type: PROTEIN_COMPLEX
description: >-
  The signal peptidase complex in the endoplasmic reticulum membrane cleaves
  N-terminal signal peptides from secretory and membrane proteins as they are
  translocated. Its catalytic subunit, SEC11 (encoded in Drosophila by
  twr), is a membrane-anchored serine protease whose active site faces the ER
  lumen. The accessory subunits SPCS1, SPCS2
  and SPCS3 (Spase12, Spase25 and Spase22-23) are required for activity and
  stability of the complex; SPCS3 also helps select substrates.
summary: >-
  ER membrane protease complex whose SEC11 subunit removes signal peptides from
  translocated proteins.
concepts:
  - {id: GO:0005787, label: signal peptidase complex}
cellular_components:
  - {id: GO:0005789, label: endoplasmic reticulum membrane}
notes: >-
  Decomposition. The catalytic subunit and the accessory subunits are modelled
  as two parts. The BP term for signal peptide processing is obsolete in GO, so
  no process term is attached.
parts:
  - id: spc_catalytic
    label: SEC11 catalytic subunit
    role: catalytic subunit
    genes: [twr]
    function: {id: GO:0009003, label: signal peptidase activity}
  - id: spc_accessory
    label: Accessory subunits
    role: structural and substrate-selecting subunits
    genes: [Spase12, Spase25, Spase22-23]