STX16

PF3D7_1243000 (STX16) is a predicted syntaxin-family SNARE protein of Plasmodium falciparum, identified computationally as one of 18 SNARE-like proteins in the parasite genome and assigned to a P. falciparum-specific syntaxin-like subfamily (PMID:17240462). Functional analysis of the VPS45-SNARE axis in apicomplexan parasites has implicated STX16, alongside TgVps45 and Stx6, in biogenesis of the inner membrane complex (alveoli) (PMID:33082261). Beyond this membership in a putative VPS45-SNARE trafficking axis, no dedicated experiment has directly established the subcellular localization, binding partners, or molecular mechanism of PF3D7_1243000 itself in the available corpus; the primary mechanistic detail rests on the co-analyzed proteins TgVps45 and Stx6 rather than on STX16 directly.

1. 2006 Low

   Before any parasite SNARE inventory existed, it was unknown which membrane-fusion machinery P. falciparum encodes; a genome-wide survey placed PF3D7_1243000 within the SNARE repertoire and defined it as a syntaxin-like protein.

   Evidence Bioinformatics/phylogenetic analysis of the P. falciparum genome, with GFP-tagging performed for other family members but not STX16

   PMID:17240462

   Open questions at the time

   • Computational identification only; no direct experiment on PF3D7_1243000
   • No subcellular localization determined for STX16
   • No binding partners or functional assay for STX16
2. 2020 Low

   Whether STX16 participates in a specific trafficking pathway was unresolved; functional study of the VPS45-SNARE axis implicated STX16 together with TgVps45 and Stx6 in inner membrane complex (alveoli) biogenesis, placing it in a candidate trafficking role.

   Evidence Genetic/functional analysis of SNARE and SEC1/Munc18 proteins in Toxoplasma gondii and P. falciparum, including localization and loss-of-function experiments

   PMID:33082261

   Open questions at the time

   • No dedicated experiment isolated STX16 function; mechanistic detail is attributed to TgVps45/Stx6
   • STX16 localization not directly established
   • Direct binding partners of STX16 not defined

• The precise molecular mechanism, subcellular localization, and direct binding partners of PF3D7_1243000 remain uncharacterized by any dedicated experiment.
• No direct localization of STX16 protein
• No reconstituted SNARE complex or partner validation for STX16
• No loss-of-function phenotype isolating STX16 specifically