Analysis of Genetic Variation in the Small Subunit Ribosomal RNA Gene of Euplotes Ciliates for Developing Species Diagnostic Molecular Marker

종 식별 분자 마커 개발을 위한 섬모충류 Euplotes의 small subunit ribosomal RNA 변이성 분석

  • Published : 2007.08.31

Abstract

To verify which loop regions of 18S rRNA gene are suitable as species-specific genetic markers in ciliates, we analyzed the genetic variation of 18S rRNA gene among 9 Euplotes species (Hypotrichia : Ciliophora). In our result, no inter-specific variation was detected from V1, V3 and V5 regions, and the length of V7 and V8 are 44 bp and 79 bp, respectively, which are too short to make genetic marker. In contrast, V2 and V4 may be good candidate segments of species-specific diagnostic molecular markers because these two regions are most variable ($1.75{\sim}20.61%$) and showed good inter-specific phylogeny. Furthermore, the sequences of V2 and V4 are 123 bp and 306 bp, respectively in length which are enough to make species-specific marker.

Small subunit ribosomal RNA (18S rRNA)의 loop 부위들의 변이를 분석하여 해양 섬모충류의 종 특이 유전적 마커로써 이용 가능성을 확인하고자 9종의 Euplotes (Hypotrichia : Ciliophora)에 대하여 18S rRNA 유전자의 염기서열 변이성을 조사하였다. 연구 결과에 의하면 V1, V3 그리고 V5 부위는 종간 변이가 없었고, V7과 V8은 종간변이는 높으나 염기서열의 길이가 각각 44 bp와 79 bp로 길이가 짧아서 충분한 유전 정보를 가지기 어렵기 때문에이 부위들은 종특이 분자마커로 적합하지 않았다. 그러나 V2와 V4부위는 $1.75{\sim}20.61%$로 높은 변이성을 보여주었고 종간 계통 관계도 잘 나타내었다. 또한 염기서열의 길이도 각각 123 bp와 306 bp로 마커 개발에 충분한 길이를 가지고 있었다. 따라서 18S rRNA의 V2와 V4부위는 섬모충류의 종 특이 분자 마커 개발에 가장 적합한 부위라는 결론을 얻었다.

Keywords

References

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