Quantitative assessment of Azumiobodo hoyamushi distribution in the tunic of soft tunic syndrome–affected ascidian Halocynthia roretzi using real-time polymerase chain reaction

Particle and Fibre Toxicology

Kyung-Il Park¹  Jong-Man Yoon¹  Kwan Ha Park¹  Ki-Woong Nam¹  Yun-Kyung Shin² 

[1] Department of Aquatic Life Medicine, College of Ocean Science and Technology, Kunsan National University, 558 Daehakno, Gunsan 573-701, Republic of Korea;National Fisheries Research and Development Institute, Busan 619-705, Republic of Korea

关键词: Soft tunic syndrome;    Real-time PCR;    Azumiobodo hoyamushi;    Halocynthia roretzi;   

Others  :  1149109
DOI  :  10.1186/s13071-014-0539-x

 received in 2014-08-21, accepted in 2014-11-13,  发布年份 2014

【 摘 要 】

Background

The kinetoplastid parasite, Azumiobodo hoyamushi, is the causative agent of soft tunic syndrome (STS) in ascidians and leads to their mass mortality in Korean waters. This study was conducted to quantify A. hoyamushi density during the development of STS in the tunics of ascidians (Halocynthia roretzi) using real-time polymerase chain reaction (qPCR).

Findings

The infection intensity of A. hoyamushi, as measured by qPCR, varied depending on the part of the tunic analyzed, as well as the stage of STS development. The highest infection intensity was recorded in the tunics of the siphons. The infection intensity of A. hoyamushi in the siphons was only 2.9 cell/tunic (area, 0.25 cm²) or 106.0 cell/gram tunic (GT) in the early phase of STS, but this value increased dramatically to 16,066 cells/tunic (0.25 cm²) or 617,004 cell/GT at the time of death. The number of A. hoyamushi parasites increased gradually and their distribution spread from the siphons to the other parts of the tunics.

Conclusions

qPCR enabled the quantitation of A. hoyamushi and the results revealed that parasite density increased as STS progressed. In addition, our results suggested that the siphons might function as the portal of entry for A. hoyamushi during infection.

【 授权许可】

   
2014 Shin et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

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