Identification of mutations in TgMAPK1 of Toxoplasma gondii conferring resistance to 1NM-PP1

Tatsuki Sugi, Kyousuke Kobayashi, Hitoshi Takemae, Haiyan Gong, Akiko Ishiwa, Fumi Murakoshi, Frances C. Recuenco, Tatsuya Iwanaga, Taisuke Horimoto, Hiroomi Akashi, Kentaro Kato

Research output: Contribution to journalArticlepeer-review

22 Citations (Scopus)


Toxoplasma gondii is an important food and waterborne pathogen that causes severe disease in immunocompromised patients. Bumped kinase inhibitors (BKIs) have an antiparasitic effect on T. gondii tachyzoite growth by targeting T. gondii calmodulin-domain protein kinase 1 (TgCDPK1). To identify mutations that confer resistance to BKIs, chemical mutagenesis was performed, followed by selection in media containing either 250 or 1000. nM 1NM-PP1. Whole-genome sequence analysis of resistant clones revealed single nucleotide mutations in T. gondii mitogen-activated protein kinase 1 (TgMAPK1) at amino acids 162 (L162Q) and 171 (I171N). Plasmid constructs having the TgMAPK1 L162Q mutant sequence successfully replaced native TgMAPK1 genome locus in the presence of 1000. nM 1NM-PP1. The inhibitory effect of 1NM-PP1 on cell division observed in the parent clone was decreased in 1NM-PP1-resistant clones; however, effects on parasite invasion and calcium-induced egress were similar in both parent and resistant clones. A plasmid construct expressing the full length TgMAPK1 splicing isoform with L162Q mutation successfully complemented TgMAPK1 function in the pressure of 250. nM 1NM-PP1 in plaque assay. 1NM-PP1-resistant clones showed resistance to other BKIs (3MB-PP1 and 3BrB-PP1) with different levels. Here we identify TgMAPK1 as a novel target for 1NM-PP1 activity. This inhibitory effect is mediated through inhibition of tachyzoite cell division, and can be overcome through mutations at multiple residues in TgMAPK1.

Original languageEnglish
Pages (from-to)93-101
Number of pages9
JournalInternational Journal for Parasitology: Drugs and Drug Resistance
Publication statusPublished - 2013 Dec
Externally publishedYes


  • 1NM-PP1
  • Bumped kinase inhibitor
  • Drug resistance
  • TgMAPK1
  • Toxoplasma gondii

ASJC Scopus subject areas

  • Parasitology
  • Infectious Diseases
  • Pharmacology (medical)


Dive into the research topics of 'Identification of mutations in TgMAPK1 of Toxoplasma gondii conferring resistance to 1NM-PP1'. Together they form a unique fingerprint.

Cite this