PF3D7_1476100

ETRAMP14.2 (PF3D7_1476100) is a member of the ETRAMP family of highly cationic membrane proteins in Plasmodium falciparum that localize to the parasitophorous vacuole membrane (PVM) at the parasite–host cell interface (PMID:12686607). Family characterization, in which ETRAMP14.2 is one member, indicates that individual ETRAMPs form oligomeric arrays defining separate PVM microdomains distinct from those of EXP-1, with recombinant family members oligomerizing intrinsically in bacterial membranes independently of other parasite proteins (PMID:12686607, PMID:16420351). mRNAs from the ETRAMP family, including transcripts from the PF3D7_1476100 locus, are exported from infected erythrocytes and imported into host immune cell nuclei, where they bind the host splicing-machinery proteins ACIN1 and PNN and disrupt host splicing and immune signaling (PMID:41689806). Beyond membership in the family-level findings (PMID:12686607, PMID:16420351, PMID:41689806), no mechanistic property specific to ETRAMP14.2 alone has been resolved in the available corpus.

1. 2003 Medium

   Establishing where the ETRAMP family, including ETRAMP14.2, resides answered whether these cationic proteins act at the parasite–host boundary, placing them at the PVM in functionally distinct domains.

   Evidence membrane fractionation, immunofluorescence with selective permeabilization, and immunoelectron microscopy in P. falciparum

   PMID:12686607

   Open questions at the time

   • Localization was characterized at the family level; the specific PVM domain occupied by ETRAMP14.2 alone is not resolved
   • No functional consequence of PVM localization tested for ETRAMP14.2 specifically
   • Topology and orientation of the single transmembrane segment not directly mapped for this member
2. 2006 Medium

   Whether ETRAMPs are monomeric or assemble into higher-order structures was addressed by showing they form oligomeric arrays and self-oligomerize intrinsically, defining how they organize into non-random microdomains.

   Evidence in vivo cross-linking and recombinant oligomerization in bacterial membranes

   PMID:16420351

   Open questions at the time

   • Oligomerization shown for the family and for three recombinant ETRAMPs; direct demonstration of ETRAMP14.2 self-assembly not isolated
   • Stoichiometry and structure of the arrays unknown
   • Functional role of oligomerization for the parasite not established
3. 2026 Medium

   The question of whether ETRAMP transcripts act beyond the parasite was addressed by showing family mRNAs, including from the PF3D7_1476100 locus, enter host immune cell nuclei and bind splicing regulators ACIN1 and PNN, revealing an mRNA-based host-manipulation route.

   Evidence nuclear fractionation, RNA immunoprecipitation identifying ACIN1/PNN, transcriptomic splicing analysis, and immune assays in P. falciparum-infected cells

   PMID:41689806

   Open questions at the time

   • Single study without independent replication; finding applies to the ETRAMP mRNA family, so the contribution of the PF3D7_1476100 transcript specifically is not isolated
   • Mechanism of mRNA export and nuclear import not defined
   • Causal link between ACIN1/PNN binding and altered immune signaling not fully dissected

• What ETRAMP14.2 does uniquely — as opposed to as one member of a collectively characterized family — remains unresolved, including its individual PVM function, essentiality, and whether its own transcript drives host splicing disruption.
• No loss-of-function or knockout phenotype reported for ETRAMP14.2 specifically
• No member-specific interaction partners at the protein level identified
• Contribution of the PF3D7_1476100 transcript to host nuclear effects not separated from other family members