BCP1

BCP1 (PF3D7_1436200) is a Plasmodium falciparum basal complex protein first identified through co-immunoprecipitation of the PfCINCH-containing complex, establishing it as a previously undescribed member of the asexual schizont basal complex (PMID:31097714). By immunofluorescence, including Airyscan super-resolution imaging, BCP1 localises to the basal complex at the leading edge of the inner membrane complex during schizogony, and this localisation persists after inducible knockout of PfMORN1 (PMID:34878291, PMID:31097714, PMID:37400439). Its consistent co-localisation with basal complex markers has made BCP1 a reference marker for validating the basal complex identity of other proteins (PMID:34878291, PMID:31097714, PMID:37400439). Beyond its membership in the basal complex, its restriction to the asexual blood stage, and its localisation behaviour, no direct loss-of-function or biochemical role for BCP1 itself has been characterized in the available corpus.

1. 2019 Medium

   Before this work the protein composition of the P. falciparum basal complex was incompletely defined; pulling down the PfCINCH complex established BCP1 as a bona fide basal complex component.

   Evidence Co-immunoprecipitation / biochemical pulldown of the PfCINCH-containing complex

   PMID:31097714

   Open questions at the time

   • Reciprocal co-IP from a single lab only
   • No functional characterisation of BCP1 itself
   • Direct binding partner within the complex not resolved
2. 2021 Medium

   It was unknown where BCP1 sits within the dividing schizont and whether its recruitment depends on other basal complex proteins; imaging placed it at the leading edge of the IMC and showed its localisation is independent of PfMORN1.

   Evidence Immunofluorescence including Airyscan super-resolution with anti-BCP1 antisera, plus inducible PfMORN1 knockout

   PMID:31097714 PMID:34878291 PMID:37400439

   Open questions at the time

   • Determinants of BCP1 recruitment to the basal complex unknown
   • No loss-of-function experiment on BCP1 itself
   • Role in basal complex constriction untested
3. 2022 Low

   Whether BCP1 functions in the transmission stage was open; its absence from gametocytes indicates its role is restricted to the asexual blood-stage basal complex rather than transmission-stage IMC expansion.

   Evidence Immunofluorescence with anti-BCP1 antisera across gametocyte stages I–V

   PMID:35972967

   Open questions at the time

   • Single-lab negative immunofluorescence result
   • Absence not confirmed by orthogonal method (e.g. transcriptomics or tagging)
   • Functional consequence of stage restriction untested
4. 2023 Low

   BCP1's reliability as a spatial reference was leveraged, with co-localisation with PfPPP8 confirming its use as a basal complex marker for validating newly identified proteins.

   Evidence Immunofluorescence co-localisation of PfPPP8-smV5 with anti-BCP1 antisera

   PMID:37400439

   Open questions at the time

   • Single co-localisation experiment
   • Provides no new mechanistic insight into BCP1's own function
   • No physical interaction with PfPPP8 tested

• The molecular function of BCP1 within the basal complex remains undefined: no loss-of-function phenotype, enzymatic activity, or direct binding partner has been established.
• No inducible knockout/knockdown of BCP1 itself
• No structural or biochemical activity assigned
• Direct molecular partners within the complex unresolved