CAJ | 학술논문

玉米转座元件Ac/Ds是hAT转座子家族的成员，导入水稻基因组后具有转座活性，尽管转座机制还不完全清楚，但它们通常经保守的非复制型“剪切-粘贴”过程转座。研究表明，在Ac编码的转座酶作用下， Ds从原位点切离后常优先重新插入到连锁位点。文章利用 TAIL-PCR技术从水稻一个 Ds插入突变体及其回复突变体中分离Ds侧翼序列，结合生物信息学分析方法，对Ds在突变体上插入位点、回复突变体内切离足迹和重新插入位点进行了分子鉴定。结果显示，突变体中Ds从3号染色体切离后，在原插入位点残留了8 bp足迹序列(CATCATGA)，引起Ds标记基因外显子和内含子数目增加，从而影响基因结构。切离后的Ds重新插入回复突变体第2和第6号染色体上，分别编码烟草胺氨基转移酶和衰老相关蛋白的2个基因的编码区。因此，典型的“剪切-粘贴”机制不能完全解释Ds的转座行为， Ds转座存在“剪切-复制-粘贴”的特点。
옥미전좌원건Ac/Ds시hAT전좌자가족적성원，도입수도기인조후구유전좌활성，진관전좌궤제환불완전청초，단타문통상경보수적비복제형“전절-점첩”과정전좌。연구표명，재Ac편마적전좌매작용하， Ds종원위점절리후상우선중신삽입도련쇄위점。문장이용 TAIL-PCR기술종수도일개 Ds삽입돌변체급기회복돌변체중분리Ds측익서렬，결합생물신식학분석방법，대Ds재돌변체상삽입위점、회복돌변체내절리족적화중신삽입위점진행료분자감정。결과현시，돌변체중Ds종3호염색체절리후，재원삽입위점잔류료8 bp족적서렬(CATCATGA)，인기Ds표기기인외현자화내함자수목증가，종이영향기인결구。절리후적Ds중신삽입회복돌변체제2화제6호염색체상，분별편마연초알안기전이매화쇠로상관단백적2개기인적편마구。인차，전형적“전절-점첩”궤제불능완전해석Ds적전좌행위， Ds전좌존재“전절-복제-점첩”적특점。
The maize Ac/Ds transposable elements are members of the hAT transposon superfamily, and have stable transpositional activity in transgenic rice plants. Ac/Ds transposable elements are considered to transpose via a conservative non-replicative“cut and paste”model, though their transposition mechanism is not completely understood. Previous studies have shown that Ds preferentially transposes to genetically linked sites after being excised from its original site in the pres-ence of Ac-transposase. In this study, genomic sequences flanking Ds insertions from a Ds-tagged rice mutant and its rever- <br> tant were determined by TAIL-PCR. The Ds insertion site, the excision footprint and the re-insertion sites in the mutant were identified using bioinformatics tool. The results showed that Ds element excised from its original insertion site on chromosome 3 by leaving an 8 bp footprint (CATCATGA), which resulted in exon changes in tagged gene. After the exci-sion, Ds element was re-inserted into the coding sequences of two genes on chromosome 2 and chromosome 6, which en-code a nicotianamine aminotransferase and a senescence-associated protein, respectively. The transposition behavior of Ds element in this study could not be fully explained by the"cut and paste"mechanism, while it is likely to transpose in a"cut and copy and paste"way.