Targeting Microcystin (MC), which is most abundantly detected in the North-Han River water area, we analyzed the relationship between the MC biosynthesis gene (mcyA gene), cyanobacteria cell density, and MC concentration, derived an RNA-MC conversion formula, and derived the cyanobacteria. The concentration of MC present in cells was predicted. In the North-Han River waters, the mcyA gene was found mainly at downstream sites of the North-Han River after Muk-Hyeon Stream junction, and higher copy numbers were found on average than other sites. In the Uiam Lake waters upstream of the North-Han River, the mcyA gene copy number increased at the Kong-Ji Stream point, and after September, the mcyA gene copy number decreased throughout the North-Han River waters. The expression of the mcyA gene was concentrated in the short period of summer due to the spatio-temporal difference between upstream and downstream water bodies. The mcyA gene expression level was not only highly correlated with MC concentration, but also correlated with the cell density of Microcystis aeruginosa and Dolichospermum circinale, which are known to biosynthesize MC. Six conversion formulas derived based on the RNA-MC relationship showed statistical significance (p<0.05) and exhibited high correlation coefficients (r) of 0.9 or higher. The expression level of MC biosynthesis gene present in eRNA determines the synthesis of cyanotoxin substances in water, quickly quantifies gene activity, and can be fully utilized for early warning of MC development.

Abstract
서 론
재료 및 방 법
    1. 조사지점 및 시료채집
    2. eDNA와 eRNA 추출
    3. eDNA와 eRNA의 정량분석 (Quantitative analysis)
    4. 남조류 세포밀도 및 Microcystin (MC) 분석
    5. 통계분석
결 과
    1. 수층에서 mcyA DNA copy number의 시·공간적 변이
    2. 수층에서 mcyA 유전자 발현 (RNA gene expression)의시·공간적 변이
    3. eRNA발현과 Microcystin (MC) 농도 사이의 관계
고 찰
적 요
REFERENCES

• 김건희(건국대학교 상허생명과학대학 휴먼앤에코케어센터) | Keonhee Kim (Human and Eco Care Center, College of Sang-huh Life Science, Konkuk University)
• 박채홍(건국대학교 상허생명과학대학 휴먼앤에코케어센터) | Chaehong Park (Human and Eco Care Center, College of Sang-huh Life Science, Konkuk University)
• 조현진(전남대학교 생물학과) | Hyeonjin Cho (Department of Biology, Chonnam National University)
• 권대률(국립낙동강생물자원관 미생물연구실 원생생물연구팀) | Daeryul Kwon (Protist Research Team, Microbial Department, Nakdonggang National Institute of Biological Resources)
• 황순진(건국대학교 환경보건과학과) | Soon-Jin Hwang (Department of Environmental Health Science, Konkuk University) Corresponding author