水稻颖壳退化突变体degraded hull 2 (dh2)的遗传分析与基因定位

作物学报 ACTA AGRONOMICA SINICA 2013, 39(6): 1039−1044

/zwxb/ ISSN 0496-3490; CODEN TSHPA9

E-mail: xbzw@

本研究由国家高技术研究发展计划(863计划)项目(2011AA10A100), 国家自然科学基金项目(31071390)和中央高校基本科研业务费专项资金(XDJK2012A001)资助。

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通讯作者(Corresponding author): 何光华, E-mail: hegh@

第一作者联系方式: E-mail: guoshuang16@(郭爽); tanhua.li@(李云峰) **同等贡献(Contributed equally to this work) Received(收稿日期): 2012-10-31; Accepted(接受日期): 2013-01-15; Published online(网络出版日期): 2013-02-19. URL: /kcms/detail/11.1809.S.20130219.1019.002.html

DOI: 10.3724/SP.J.1006.2013.01039

水稻颖壳退化突变体degraded hull 2 (dh2)的遗传分析与基因定位

郭 爽** 李云峰** 任德勇 张天泉 何光华*

西南大学水稻研究所 / 转基因植物与安全控制重庆市重点实验室, 重庆 400716

摘 要: 鉴定和克隆水稻花器官突变体新基因, 对了解水稻花器官发育的分子遗传机制和分子信号调控途径有重要作用。本研究报道了1个水稻颖壳异常突变体, 来源于EMS (ethyl methane sulfonate)处理的缙恢10号(Oryza sativa )诱变群体, 暂被命名为degraded hull 2 (dh2)。表型分析发现突变体小花第1轮内稃或外稃横向细胞数目减少, 导致内稃或外稃变窄而不能正常勾合, 从而呈现开裂现象, 其内3轮花器官均无明显变化。遗传分析表明该突变性状受1个隐性单基因控制。利用群体分离分析法(bulked segregation analysis, BSA), 将DH2基因定位在第3染色体的IND-5和IND-14之间, 遗传距离分别为0.99 cM 和1.49 cM 。该研究结果为DH2基因的图位克隆奠定了基础。 关键词: 水稻; degraded hull 2 (dh2); 遗传分析; 基因定位

Genetic Analysis and Gene Mapping of a degraded hull 2 (dh2) Mutant in Rice (Oryza sativa )

GUO Shuang **, LI Yun-Feng **, REN De-Yong, ZHANG Tian-Quan, and HE Guang-Hua *

Rice Research Institute / Chongqing Key Laboratory of Application and Safety Control of Genetically Modified Crops, Southwest University, Chongqing 400716, China

Abstract: The identification and cloning of novel mutant genes of floral organ in rice play an important role in understanding the molecular genetic mechanisms and molecular signal pathways regulating floral organ development. A rice mutant, degraded hull 2 (dh2), which was derived from ethylmethane sulfonate (EMS)-treated Jinhui 10 (Oryza sativa ), exhibited defects in hull develop-ment. The dh2 florets displayed open hull in whorl 1, however, the rest floral parts in other three whorls had no obvious change. Further analysis indicated that the number of transverse cells decreased, making the lemma or palea narrow, and causing the hull open. The genetic analysis revealed that the dh2 trait is controlled by a single recessive gene. Using the BSA method, the DH2 gene was finally mapped between IND-5 and IND-14 on chromosome 3 with genetic distances of 0.99 cM and 1.49 cM, respec-tively. These results are useful for the map-based cloning of DH2 gene.

Keywords: Rice (Oryza sativa ); degraded hull 2 (dh2); Genetic analysis; Gene mapping

单子叶植物的花器官与双子叶植物存在较大差异, 其发育调控机制的异同一直吸引着许多科学家的注意。水稻被认为是单子叶的模式植物, 其花器官由外向内由1对稃片(内稃和外稃)、1对浆片、6枚雄蕊和1个雌蕊构成。就形态与功能而言, 内轮花器官雄蕊和雌蕊与双子叶植物类似, 而外轮花器官内外稃、浆片与双子叶植物的花萼、花瓣相比都存在明显的差异。

通过对模式植物拟南芥及金鱼草的广泛研究,

双子叶花器官发育的分子遗传学机制取得了长足的进展, 提出了经典的花发育ABCE 模型[1-5]。该模型认为花器官特征发育主要受A 、B 、C 和E 四类花器官特征基因的组合调控, 4轮结构即花萼、花瓣、雄蕊及心皮分别由A+E 、A+B+E 、B+C+E 及C+E 共4组基因决定, 每一类基因都调控两轮或两轮以上的花器官, 其中任何一类基因的突变都会引起相应轮次器官的同源异型转变[2,5]。

近年来, 人们在禾本科的水稻、玉米等作物中鉴定