SAS4

SAS4/CPAP has been identified only by comparative genomics as a conserved UNIMOD component present in apicomplexan genomes, including Toxoplasma gondii and Plasmodium, alongside the basal body factors SAS6 and BLD10/CEP135 (PMID:26855772). This co-conservation places SAS4 among candidate basal body assembly machinery in these parasites (PMID:26855772). Beyond this genomic identification (PMID:26855772), no direct experimental study has characterized SAS4's molecular activity, localization, or functional role in Toxoplasma centriole or basal body assembly in the available corpus.

1. 2016 Low

   Whether the canonical centriole/basal body assembly machinery is conserved in apicomplexan parasites was unclear; identifying SAS4/CPAP alongside SAS6 and BLD10/CEP135 in these genomes established that this machinery is retained in Toxoplasma and Plasmodium.

   Evidence Comparative genomics and review of ultrastructural data across apicomplexan genomes

   PMID:26855772

   Open questions at the time

   • Computational/genomic identification only; no direct functional experiment performed on the SAS4 protein
   • SAS4 localization to the basal body or centriole in Toxoplasma is not experimentally demonstrated
   • No molecular activity, interaction partners, or assembly role established

• The specific molecular mechanism and functional role of SAS4/CPAP in Toxoplasma centriole or basal body assembly remains unestablished.
• No experimental localization data
• No knockout/knockdown phenotype
• No demonstrated protein interactions or biochemical activity