STX6

PF3D7_1452500 (STX6) is a predicted SNARE-like protein of Plasmodium falciparum, identified computationally as one of 18 P. falciparum SNARE-like proteins and assigned to a P. falciparum-specific syntaxin-like subfamily (PMID:17240462). Functional analysis of apicomplexan SNARE and SEC1/Munc18 proteins implicates STX6 in biogenesis of the inner membrane complex (alveoli), acting in coordination with TgVps45 and Stx16 (PMID:33082261); this role in P. falciparum was inferred largely from experiments in Toxoplasma gondii rather than demonstrated by direct functional experiments on STX6 in P. falciparum. Beyond its computational classification (PMID:17240462) and this inferred pathway assignment (PMID:33082261), no direct experimental characterization of STX6 function, membrane fusion activity, or interaction partners in P. falciparum has been reported in the available corpus.

1. 2006 Low

   Establishing whether P. falciparum encodes a syntaxin-6-like SNARE at all, this genome-wide survey placed STX6 within a parasite-specific syntaxin-like subfamily and flagged atypical SNARE structural features.

   Evidence Comprehensive bioinformatics/phylogenetic analysis of the P. falciparum genome

   PMID:17240462

   Open questions at the time

   • Computational prediction only; no functional experiment on STX6
   • SNARE membrane fusion activity not demonstrated
   • Subcellular localization of STX6 not determined
2. 2020 Low

   Addressing what cellular process STX6 might serve, functional analysis of apicomplexan SNARE/SEC1-Munc18 proteins implicated STX6 in inner membrane complex (alveoli) biogenesis alongside TgVps45 and Stx16.

   Evidence Conditional knockdown/localization of SNARE and SEC1/Munc18 proteins in Toxoplasma gondii and P. falciparum, with inner membrane complex biogenesis as phenotypic readout

   PMID:33082261

   Open questions at the time

   • STX6 role in P. falciparum inferred from T. gondii experiments; no direct functional experiment on STX6 in P. falciparum described
   • Physical interaction of STX6 with TgVps45 or Stx16 not directly demonstrated for the P. falciparum protein
   • Mechanism of STX6 in alveoli membrane fusion unresolved

• Whether STX6 mediates membrane fusion, which SNARE partners and tethering factors it engages in P. falciparum, and its native subcellular localization remain unestablished by direct experiment.
• No direct P. falciparum functional assay for STX6
• No experimentally validated interaction partners
• No structural or fusion-activity data