MyoK

MyoK (PF3D7_1140500) is a putative myosin of Plasmodium whose transcript is present and developmentally regulated across asexual blood stages of P. falciparum (PMID:15754360), and whose gene is likely essential for asexual blood-stage proliferation in P. berghei, where knockout attempts failed (PMID:31283102). In P. berghei sexual stages, MyoK has been identified as a putative interactor of the aurora-related kinase ARK2, co-localising with ARK2 at spindle microtubules near kinetochores during mitosis and meiosis (PMID:37704606). Beyond this membership in the ARK2 interactome and its likely essentiality, the molecular activity, motor function, and mechanism of action of MyoK have not been characterized in the available corpus.

1. 2005 Low

   Establishing whether MyoK is expressed at all in blood-stage parasites was the first step; RT-PCR showed its transcript is present and developmentally regulated, indicating the gene is transcribed during asexual proliferation.

   Evidence RT-PCR on blood-stage parasite mRNA across developmental stages in P. falciparum

   PMID:15754360

   Open questions at the time

   • Transcript detection only; no protein-level expression or translation timing established for MyoK
   • No functional or mechanistic role assigned
   • Single lab, single method
2. 2019 Medium

   Whether MyoK is required for parasite viability was addressed by attempting gene deletion; failure to recover knockouts indicated the gene is likely essential in asexual blood stages, marking it as functionally important despite its uncharacterized role.

   Evidence Gene deletion / knockout attempt in P. berghei with assessment of asexual blood-stage essentiality

   PMID:31283102

   Open questions at the time

   • 'Likely essential' inferred from failed deletion rather than a conditional knockout with a defined phenotype
   • No mechanistic explanation for why the gene is essential
   • Single lab, single method
3. 2023 Low

   The first physical/spatial context for MyoK came from ARK2 interactomics, which identified MyoK as a putative ARK2 interactor co-localising at spindle microtubules near kinetochores, placing MyoK in the vicinity of the sexual-stage division machinery.

   Evidence Co-IP/pulldown mass spectrometry with super-resolution and live-cell fluorescence co-localisation in P. berghei sexual stages

   PMID:37704606

   Open questions at the time

   • Single Co-IP/MS identification described as 'putative' with no reciprocal validation of the MyoK–ARK2 interaction specifically
   • No functional test of what MyoK does at the spindle
   • Interaction and localisation shown in sexual stages, not asexual stages where essentiality was inferred

• The core molecular function of MyoK — whether it acts as an active motor, its binding partners, its cargo or filament substrate, and how its likely essentiality relates to its spindle-associated localisation — remains unresolved.
• No demonstrated motor or enzymatic activity for MyoK
• No conditional knockout linking essentiality to a specific cellular process
• MyoK–ARK2 interaction not functionally validated