Cytochrome Oxidase 2 (COX2), β-Tubulin (TUB) and Chitin Synthase Subunit 2 (CHS2) Expression in Pythium insidiosum Thai Strains


  • Patcharee KAMMARNJASSADAKUL Faculty of Medical Technology, Huachiew Chalermprakiat University, Samut Prakan 10540, Thailand
  • Watcharin RANGSIPANURATN Faculty of Medical Technology, Huachiew Chalermprakiat University, Samut Prakan 10540, Thailand
  • Methee SRIPRAPUN Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand
  • Popchai NGAMSAKULRUNGRUJ Faculty of Medicine Siriraj Hospital, Mahihol University, Bangkok 10400, Thailand
  • Tanapat PALAGA Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
  • Kallaya SRITUNYALUCKSANA Faculty of Science, Mahidol University, Bangkok 10400, Thailand
  • Ariya CHINDAMPORN Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand



Chitin synthase 2, Cytochrome oxidase 2, Expression, Pythium insidiosum, Tubulin


This study aimed to investigate the real-time fluctuation of temperature-sensitive gene expression in a Pythium insidiosum growing at human body temperature (37 ºC) when it can cause life-threatening disease, whereas its natural habitat is in agricultural water sources with lower temperature. Genes encoding cytochrome oxidase 2 (COX2), β-tubulin (TUB), and chitin synthase subunit 2 (CHS2) were tested for their expression at the infection temperature (37 ºC) and natural habitat temperature (27 ºC) using real-time RT-PCR. Sixteen strains of P. insidiosum, representing 3 phylogeographic preferences, were analyzed. The subculturing process at 27 ºC was repeated at least 2 - 3 cycles. The results showed that at 37 ºC, the COX2 was expressed 2.5-fold higher than that of 27 ºC (p = 0.0347) while the level of TUB and CHS2 mRNA disclosed indistinguishable profiles. These results suggested that these genes were suitable to be used as housekeeping genes for temperature-susceptible gene expression studies. This work was likely to be the 1st study examining the gene expression levels of the Thai strain of P. insidiosum under thermal stress conditions. Follow-up studies for the COX2 genes may useful to provide valuable insight into the pathogenesis, diagnostic, or therapeutic targets for further investigation.


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How to Cite

KAMMARNJASSADAKUL, P. ., RANGSIPANURATN, W. ., SRIPRAPUN, M. ., NGAMSAKULRUNGRUJ, P. ., PALAGA, T. ., SRITUNYALUCKSANA, K. ., & CHINDAMPORN, A. . (2021). Cytochrome Oxidase 2 (COX2), β-Tubulin (TUB) and Chitin Synthase Subunit 2 (CHS2) Expression in Pythium insidiosum Thai Strains. Walailak Journal of Science and Technology (WJST), 18(8), Article 9433 (8 pages).