과제정보
This work was carried out with the support of "Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ007884)" Rural Development Administration, Republic of Korea.
국화과(Compositae)는 현화식물 중 세계에서 가장 넓게 분포하고, 쌍자엽식물 중 가장 진화된 식물분류군이며, 우리나라에는 약 300여종이 존재하는 것으로 알려져 있다. 구절초, 감국, 쑥, 쑥갓, 개미취, 참취, 곰취 등 국화과 식물들은 예로부터 민간에서 약용 및 식용 소재로써 다양하게 사용되어왔다. 본 연구는 국화 및 국화근연종 유용유전자원 선발을 통하여 육종 소재를 확대하고, 중간모본 및 신품종 육성기반을 구축하고자 DNA 마커시스템의 개발을 위해 수행되었다. 1. 화단국인 Smileball(Dendranthema grandiflorum) 품종을 사용하여 SSR-enriched library를 작성하였고, GS FLX 분석을 통해 18.83Mbp의 염기서열 결과를 얻었으며, read의 평균 길이는 280.06bp로 나타났다. 2. 단순반복염기서열(SSR) 부위를 포함하는 26,780개 clones 중 di-nucleotide motifs가 16,375개(61.5%)로 우세하였고, tri-nucleotide motifs(6,616개, 24.8%), tetra-nucleotide motifs(1,674개, 6.3%), penta-nucleotide motifs(1,283개, 4.8%), hexa-nucleotide motifs(693개, 2.6%) 순으로 나타났다. 3. 얻어진 di-nucleotide motifs들 중에서는, AC/CA class가 93.5%로 대부분이었고, tri-nucleotide motifs에서는 AAC class가 50.5%, tetra-nucleotide motifs는 ACGT class가 43.6%이고, penta-nucleotide motif에서는 AACGT class 27.2%이며, hexa-nucleotide motif에서는 ACGATG class 21.8%였다. 4. 얻어진 염기서열 결과를 토대로 다양한 motif를 갖는 100개의 SSR 마커를 제작하였고, 차후 이를 활용하여 국화 유전자원의 다형성 및 유전자형 분석을 통해 분자유전학적 다양성 및 집단의 구조분석이 가능하고, 국화의 분자육종기반 구축을 위한 유용한 도구가 될 것 이다.
Chrysanthemums, often called mums or chrysanths, belong to the genus Chrysanthemum, which includes about 30 species of perennial flowering plants in the family Asteraceae. We extracted DNA from Dendranthema grandiflorum ('Smileball') to construct a simple sequence repeat (SSR)-enriched library, using a modified biotin-streptavidin capture method. GS FLX (Genome Sequencer FLX System which provides the flexibility to perform the broad range of applications) sequencing (at the 1/8 run specification) resulted in 18.83 mega base pairs (Mbp) with an average read length of 280.06 bp. Sequence analyses of all SSR-containing clones revealed a predominance of di-nucleotide motifs (16,375, 61.5%) followed by tri-nucleotide motifs (6,616, 24.8%), tetra-nucleotide motifs (1,674, 6.3%), penta-nucleotide motifs (1,283, 4.8%), and hexa-nucleotide motifs (693, 2.6%). Among the di-nucleotide motifs, the AC/CA class was the most frequently identified (93.5% of all di-nucleotide types), followed by the GA/AG class (6.1%), the AT/TA class (0.4%), and the CG/GC class (0.03%). When we analyzed the distribution of different repeat motifs and their respective numbers of repeats, regardless of the motif class, of 100 SSR markers, we found a higher number of di-nucleotide motifs with 70 to 80 repeats; we also found two di-nucleotide motifs with 83 and 89 repeats, respectively, but their product lengths were within optimum size (297 and 300 bp). In future work, we will screen for polymorphisms of possible primer pairs. The results will provide a useful tool for assessing molecular diversity and investigating the population structure among and within Chrysanthemum species.
This work was carried out with the support of "Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ007884)" Rural Development Administration, Republic of Korea.