雄性不育（male sterility,MS）在自然界高等植物中广泛存在,是指雌配子发育正常而雄配子发育异常,且与外来花粉正常受精结实的遗传现象,主要包括细胞质雄性不育（cytoplasmic male sterility,CMS）和细胞核雄性不育（genic male sterility,GMS）。CMS又称核质互作雄性不育,是一种由花粉败育进而导致受精结实异常的母性遗传现象,受线粒体不育基因和育性恢复（restorer of fertility,Rf）基因共同调控。CMS和Rf作用模式主要由细胞质线粒体基因导致雄性不育,而Rf能改变线粒体中不育基因的转录或表达,使育性得以恢复[1]。水稻（Oryza sativa L.）是全球最重要的三大粮食作物之一,世界上超过50%的人群以稻米为主食,因此水稻的高产、稳产与全球粮食安全和社会稳定密切相关。利用杂种优势能有效提高农作物产量、品质和抗性,而水稻CMS是三系杂交稻杂种优势利用的重要途径。水稻三系的CMS和Rf系统成功配套极大推动了水稻杂种优势的利用和杂交水稻在中国大规模推广应用。中国杂交水稻种植面积超过50%,占全国水稻总产量的60%以上[2],为我国乃至世界粮食增产做出了卓越的贡献。
1954年Sampath和Mohauty首次报道了水稻CMS现象后,国内外学者开始设想通过不育系选育实现杂种优势在水稻生产上应用;随后在1958年,日本Katsuo等利用中国红芒野生稻与日本粳稻藤板5号杂交,育成世界上首个具有中国红芒野生稻细胞质的藤板5号不育系[3]。
1964年,袁隆平[4]提出了利用三系法实现水稻杂种优势利用的构想,开启了我国杂交水稻研究的征程。随着分子生物学研究的发展,分子克隆与生物信息学技术不断成熟并得到广泛应用,对各种不育类型育性恢复机理的研究也越来越深入。本文主要综述了水稻CMS机制、Rf基因的来源、育性恢复遗传、定位克隆以及育种应用等方面的研究工作。
1 水稻细胞质雄性不育基因的克隆及其不育机理研究
发现并利用水稻雄性不育系是发展杂交水稻的必要前提和重要的物质基础。迄今为止,育成的水稻CMS胞质类型十分丰富,已达60多种,主要包括野败型（CMS-WA）、矮败型（CMS-DA）、D型、冈型（CMS-GA）、印水型（CMS-ID）、红莲型（CMS-HL）、马协型（CMS-MX）、万恢型（CMS-NX）、爪哇型（CMS-LX）、Y型、K52型（CMS-K）、包台型（CMS-BT）、滇型（CMS-DT）和D1型（CMS-D1）[5,6,7],其中前10种主要用于籼稻,而后4种用于粳稻,这些不同类型CMS根据其恢保关系大致分为CMS-WA、CMS-HL和CMS-BT三大类型。CMS-D1是孢子体雄性不育,无花粉型败育,为东乡野生稻特有,其恢保关系不同于其他孢子体不育类型[7]。目前已有7个水稻CMS相关基因被克隆,分别是CMS-WA型的WA352、CMS-BT型的orf79、CMS-HL型的orfH79、CMS-CW型的orf307、CMS-RT98型的orf113、CMS-RT102型的orf352和CMS-D1型的orf182[7,8,9,10,11,12,13]。
自20世纪70年代以来,CMS-WA型已在三系杂交水稻的生产中得到广泛应用,但其不育的分子机理直到最近才逐渐明晰[8]。直到2002年,第1个水稻线粒体基因组测序完成提高了对水稻细胞质不育分子机制的认识。Luo等[8]发现了水稻CMS-WA型的不育基因,并阐明了其产生的分子机制。通过对整个CMS-WA线粒体基因组的转录本进行检测分析,发现了1个新的嵌合开放阅读框,其编码1个含有352个氨基酸的蛋白质,该蛋白质具有3个跨膜区域,命名为WA352;进一步通过线粒体转运信号（MTS）与候选基因核转化融合检测其功能,表明WA352是导致CMS-WA型的不育基因[8]。该研究[8]还表明,COX11是不育蛋白WA352发挥作用的互作因子和细胞色素c氧化酶（Cyt c）的组装因子,能清除活性氧（ROS）。而ROS通过影响线粒体的通透性来促进Cyt c向细胞质释放,进而触发动物或植物程序性细胞死亡（programmed cell death,PCD）。简而言之,WA352能特异地在小孢子母细胞期的绒毡层积累并与COX11相互作用,从而抑制COX11清除活性氧的功能,导致ROS积累,Cyt c释放,进而引起绒毡层PCD异常,最终导致CMS-WA型花粉败育。
Yi等[14]利用CMS-HL粤泰A与粤泰B构建的线粒体基因组BAC文库,在粤泰A线粒体基因组atp6基因下游200bp处发现了1个编码79个氨基酸的开放性阅读框（open reading frame,ORF）,命名为orfH79,其转录产物ORFH79主要存在于CMS-HL水稻的线粒体中,而在可育系中缺失。进一步将不育基因orfH79融合为线粒体转运肽序列并转化至野生型水稻,其表达诱导配子体雄性不育表型;其转基因植株的花粉中ROS积累过多,ATP/ADP值、线粒体膜电位和呼吸速率均降低,并且初生根和侧根生长迟缓,根尖ROS积累异常,造成配子体雄性不育,这表明orfH79可导致CMS-HL水稻细胞配子体雄性不育[10]。
CMS-BT不育系来源于印度籼稻Chinsurah BoroⅡ,其细胞质的线粒体基因组中含有N-atp6和B-atp6 2个atp6基因的拷贝,组成型转录共编码ATPase复合物的亚基。B-atp6下游存在1个编码含有79个氨基酸的细胞毒性蛋白orf79基因,其C端对细胞毒性是必要的;同时该基因的功能互补结果也证实了orf79就是CMS-BT不育基因。orf79基因编码的细胞毒肽对大肠杆菌具有毒性作用,在花药小孢子中特异性积累,导致花粉败育[9]。
CMS发生的分子机制多样,目前有关植物CMS形成机理主要可归纳为如下4种假说：
1.1 细胞毒性机理假说
细胞毒性是指由细胞或化学物质引起的细胞损伤事件,不依赖于凋亡或坏死的细胞死亡机理。Dewey等[15]首次提出了线粒体异常基因编码细胞毒性的假说,认为CMS基因的产物能造成花药孢子体和配子体细胞线粒体功能受损,导致雄性不育。大多数CMS蛋白具有典型的细胞毒蛋白特征（10~35kDa的跨膜蛋白,含有一个疏水区域）。
1.2 异常细胞程序性死亡假说
PCD是生物体发育过程中普遍存在的,是生物体在生长发育过程中由自身基因决定的主动有序的死亡方式,是生物体新陈代谢过程中正常的生理反应。从小孢子发生到雄配子体发育成熟的不同阶段,小孢子或雄配子体异常的PCD都会造成植物细胞质雄性不育,其中一部分是由绒毡层细胞PCD异常造成的,还有一部分是由减数分裂过程中特定阶段的PCD异常所引起[16]。
1.3 线粒体能量供给紊乱假说
细胞生命活动所需95%的能量来自线粒体,线粒体在植物的生长发育尤其是生殖生长过程中极为重要。花药细胞发育所需要的能量比其他部位的细胞所需能量更多,因此花药细胞可能会通过增加线粒体数目或代谢活性产生更多的能量[17]。在该假说中,线粒体CMS基因的产物会造成线粒体的能量代谢异常,不能产生足够的能量,影响孢子体和配子体的正常发育,从而导致花粉败育。
1.4 反向调控假说
总而言之,CMS的形成涉及复杂的信号调控和代谢过程,毒性蛋白、早期异常PCD和能量不足可能是形成CMS机制的一部分。无论引发水稻CMS现象的分子机制如何,孢子体（主要是绒毡层）或配子体细胞都会因为线粒体氧化还原过程或能量产生异常而死亡,最终导致花粉败育。
2 三系杂交稻恢复系恢复基因的来源
水稻CMS和Rf基因的发掘和利用使我国杂交水稻的研究水平大幅提升。三系杂交稻的商业化应用除了需培育出优良的不育系外,还要选育与之配套的优良恢复系。因此,在三系杂交水稻研究的过程中,恢复基因的研究倍受关注。
有关水稻恢复基因的研究最早可追溯到20世纪60年代,许多学者开始对恢复基因的来源进行探索性研究。1972年,Shinjyo[21,22]发现强恢复品种主要分布在仅种植粳稻和籼稻的热带地区,而来自日本及其他温带国家或地区的水稻品种绝大部分为非恢品种。1970年我国培育出野败型CMS-WA的不育细胞质,1973年以袁隆平为首的全国杂交水稻协作攻关小组从东南亚品种中筛选到强恢复系[23]。自此,相继培育了许多恢复系,然而这些骨干恢复系大多来源于低纬度地区的籼稻品种。与之不谋而合的是,多项研究均表明,恢复基因频率在热带比在亚热带或温带地区高。随后对印度的冬稻（aman）、秋稻（aus）和夏稻（boro）3个生态型籼稻品种进行研究,结果表明,冬稻和夏稻品种筛选出恢复系的频率比秋稻品种更高。而印尼的“布鲁稻”（bulu）和“久来稻”（tjereh）2个生态型品种和爪哇岛的“久来稻”品种具有强恢复力。在亚洲范围内,强恢复系主要在南亚、东南亚和我国华南;在美国,仅种植粳稻的加利福尼亚州未发现强恢复系,而在主要种植籼稻的路易斯安那州和得克萨斯州筛选出3个强恢复系[24]。综上,起源于低纬度地区的水稻品种恢复系频率高于起源于高纬度地区的水稻品种,籼稻品种的恢复系频率高于粳稻品种。
3 水稻恢复基因经典遗传学研究
20世纪70年代后期以来,大量的水稻育性恢复遗传研究表明,胞质雄性不育性均可被相应的恢复基因所恢复。一般认为,CMS-WA及其恢保关系相类似的胞质不育类型的育性恢复主要受2对基因或单个主效基因控制[34,35,36]。CMS-BT和CMS-HL的育性恢复主要由1对基因控制[37,38]。此外,微效基因对细胞质雄性不育的育性恢复也具有一定的影响。恢复等位基因在一些基因位点上表现出特定的多态性,且完全恢复不同类型CMS的不育性所需的恢复基因数目不等[34,35,36,37,38]。由此可见,恢复基因对不育性的恢复作用具有专效性。这些经典遗传学研究均采用一般经验标准将群体划分为不同的育性组别,然后根据经典遗传理论和统计分析方法推断控制性状的基因对数、不同基因的相对效应及基因间互作存在与否。实际上,大多数群体的育性分离呈双峰型连续分布,少数群体的育性分离呈典型的正态分布或多峰分布,育性群体无法明确划分“育”和“不育”的界限。因此,胞质雄性不育的育性恢复受主效基因控制的同时,还可能受微效基因的修饰作用。可见水稻胞质不育性恢复遗传机理十分复杂。
4 水稻恢复基因的定位与克隆
分子生物学技术的快速发展,极大地推动了水稻细胞质雄性不育及其育性恢复的分子机理研究。自20世纪70年代起,国内外研究者对野败型（CMS-WA）、红莲型（CMS-HL）、包台型（CMS-BT）和矮败型（CMS-DA）等不同类型CMS开展了育性恢复QTL分析,在水稻12条染色体上检测到超过75个不同胞质类型育性恢复QTL,其表型贡献率介于2.9%~61.9%。然而,由于不同学者采用的研究材料及育性指标不同,其QTL定位结果也不尽相同。
4.1 野败型胞质不育恢复基因定位
表1 水稻CMS-WA育性恢复QTL
Table 1
| 胞质类型 Type of cytoplasm | QTL | 染色体 Chromosome | 区间 Interval | 群体材料 Population | 恢复基因来源 Source of Rf | 参考文献 Reference |
|---|---|---|---|---|---|---|
| WA | Rf3 | 1 | RM443-RM315 | IR58025A/IR42686R | IR42686R | [40] |
| WA | qRf-1-1 | 1 | RG140 | Neda-A/IR36 | IR36 | [41] |
| WA | qRf-1-2 | 1 | RM7180 | Neda-A/IR36 | IR36 | [41] |
| WA | Rf3 | 1 | RM1-RM3873 | Neda-A/IR36 | IR36 | [42] |
| WA | Rf3 | 1 | DRRM-RF3-5-DRRM-RF3-10 | IR58025A/KMR3RIR68897A/ DR714-1-2R | KMR3R DR714-1-2R | [43] |
| WA | qRf1 | 1 | RG532-RG472 | 珍汕97A/密阳46 | 密阳46 | [44] |
| WA | Rf3 | 1 | RM1 | Neda-A/IR36、Neda-A/IR60966 | IR36\IR60966 | [45] |
| WA | Rf | 1 | RM1 | 珍汕97A/明恢63 | 明恢63 | [46] |
| WA | qUSS-1 | 1 | RM151-RM8083 | 珍汕97A/9311 | 9311 | [47] |
| WA | qBSS-1 | 1 | RM151-RM8083 | 珍汕97A/9311 | 9311 | [47] |
| WA | Rf3 | 1 | RM10338-RM10376 | 珍汕97A/明恢63 | 明恢63 | [48] |
| WA | Rf3 | 1 | RM283-RM490 | IR58025A/IR34686R | IR34686R | [49] |
| WA | Rf i-1 | 1 | RG345-RG233 | 圭630/02428 | 圭630 | [39] |
| WA | Rf i-2 | 2 | RZ404c-RG241b | 圭630/02428 | 圭630 | [39] |
| WA | Rf i-3 | 3 | RG69a-RG413 | 圭630/02428 | 圭630 | [39] |
| WA | Rf i-4 | 4 | C22-RG449d | 圭630/02428 | 圭630 | [39] |
| WA | Rf i-5 | 5 | RG435-RG172a | 圭630/02428 | 圭630 | [39] |
| WA | Rf i-6 | 6 | RG119a-G30 | 圭630/02428 | 圭630 | [39] |
| WA | qBSS-6 | 6 | RM589-RM584 | 珍汕97A/9311 | 9311 | [49] |
| WA | Rf4 | 7 | RM6344 | IR58025A/IR42686R | IR42686R | [40] |
| WA | qRf7 | 7 | RZ395-RZ989 | 珍汕97A/密阳46 | 密阳46 | [44] |
| WA | qUSS-8 | 8 | RM506-RM152 | 珍汕97A/9311 | 9311 | [47] |
| WA | Rf i-7 | 10 | ZG3-G333 | 圭630/02428 | 圭630 | [39] |
| WA | Rf6 | 10 | RM258-RM591 | IR58025A/IR42686R | IR42686R | [40] |
| WA | Rf4 | 10 | RM171-RM228 | 珍汕97A/IR24 | IR24 | [51] |
| WA | Rf4 | 10 | DRCG-RF4-14-DRCG-RF4-8 | IR58025A/KMR3R IR68897A/DR714-1-2R | KMR3R DR714-1-2R | [43] |
| WA | Rf4 | 10 | RM258 | IR58025A/PRR-78 | PRR-78 | [52] |
| WA | Rf5 | 10 | RM311-RM171 | Neda-A/IR62030 | IR62030 | [45] |
| WA | Rf4 | 10 | RM171 | Neda-A/IR60966 | IR60966 | [45] |
| WA | Rf4 | 10 | RM311-RM6100 | IR58025A/KMR3R IR62829A/IR10198R | KMR3RIR10198R | [53] |
| WA | Rf4 | 10 | RM6737-RM171 | Neda A/Amol1 | Amol1 | [54] |
| WA | Rf | 10 | RM258-RM304 | 珍汕97A/明恢63 | 明恢63 | [46] |
| WA | qRf10 | 10 | RZ811-RG561 | 珍汕97A/密阳46 | 密阳46 | [44] |
| WA | Rf4 | 10 | RM269-RM1108 | IR58025A/IR34686R | IR34686R | [49] |
| WA | Rf4 | 10 | RM6737-RM6100 | Pusa6A/PRR78 | PRR78 | [55] |
| WA | qRf11 | 11 | RG118-RG167 | 珍汕97 A/密阳46 | 密阳46 | [44] |
| WA | qUSS-11 | 11 | MRG5615-RM202 | 珍汕97A/9311 | 9311 | [47] |
| WA | qBSS-11 | 11 | MRG5615-RM202 | 珍汕97A/9311 | 9311 | [47] |
| WA | Rf i-8 | 12 | G148a-S14 | 圭630/02428 | 圭630 | [39] |
| WA | Rf7(t) | 12 | RM7003 | IR58025A/IR42686R | IR42686R | [40] |
在1号染色体上共检测到13个育性恢复QTL[39,40,41,42,43,44,45,46,47,48,49,50],其中10个QTL成簇分布于染色体的短臂端,有4个贡献率大于32%。在10号染色体上检测到了13个育性恢复QTL[39-40,43-46,49-55],成簇分布于长臂端,其中庄杰云等[44]定位到的QTL qRf1表型贡献率最大,为43.0%;Ngangkham等[55]将育性恢复QTL Rf4精细定位至区间RM6737~RM6100,其物理位置约104kb。2、3、4、5和8号染色体上各定位到1个育性恢复QTL,其中位于3和4号染色体上的Rfi-3和Rfi-4的贡献率均大于35%,为主效QTL。而在6、7、11和12号染色体上共检测到9个育性恢复QTL,其遗传效应均为微效[39,44,47]。上述研究报道认为,野败型恢复基因主要受2对主效基因控制,但各自的效应大小不同,表现出累加效应,且受微效基因的影响。
4.2 红莲型胞质不育恢复基因定位
CMS-HL不育胞质来源于海南红芒野生稻,属于典型的配子体不育类型,迄今共定位到8个育性恢复QTL,分布于1、8和10号染色体上[56,57,58,59,60,61,62]（表2）。Shen等[62]在水稻1号染色体长臂端检测到1个红莲型育性恢复QTL,介于区间RG374~RG394。在8号染色体上定位到2个育性恢复QTL[59,60],Huang等[60]将其精细定位至区间RM407~SNP32,物理位置约16.8kb。在10号染色体定位到5个育性恢复QTL[56-58,61],成簇分布在该染色体长臂端相似区域,其中Hu等[57]将育性恢复QTL Rf5精细定位至区间RM6469~RM25659,物理位置约67kb;刘航等[54]检测到1个红莲型恢复基因的主效QTL qRF-10-1,同时还受其他几个微效QTL的影响。上述研究表明,CMS-HL育性恢复QTL主要位于8和10号染色体上。
表2 水稻CMS-HL育性恢复QTL
Table 2
| 胞质类型 Type of cytoplasm | QTL | 染色体 Chromosome | 区间 Interval | 群体材料 Population | 恢复基因来源 Source of Rf | 参考文献 Reference |
|---|---|---|---|---|---|---|
| HL | Rf5 | 1 | RG374-RG394 | II-32A/E15 | E15 | [62] |
| HL | Rf6 | 8 | RM3710-RM407-RM22242 | 粤泰A/9311 | 9311 | [59] |
| HL | Rf6 | 8 | RM407-SNP32 | 粤泰A/9311 | 9311 | [60] |
| HL | Rf5 | 10 | HL01-MRG4456 | 丛广41A/密阳23 | 密阳23 | [58] |
| HL | Rf5 | 10 | RM1108-RM5373 | 粤泰A/9311 | 9311 | [61] |
| HL | Rf5 | 10 | RM6469-RM25659 | 粤泰A/密阳23 | 密阳23 | [57] |
| HL | Rf6(t) | 10 | SBD01-SBD07 | 粤泰A/9311 | 9311 | [61] |
| HL | qRf-10-1 | 10 | RM258-C16 | Lemont/特青 | Lemont | [56] |
4.3 包台型胞质不育恢复基因定位
表3 水稻CMS-BT育性恢复QTL
Table 3
| 胞质类型 Type of cytoplasm | QTL | 染色体 Chromosome | 区间 Interval | 群体材料 Population | 恢复基因来源 Source of Rf | 参考文献 Reference |
|---|---|---|---|---|---|---|
| BT | Rf-1 | 10 | OSRRf | Taichung 65/Chinsurah BoroⅡ | Chinsurah BoroⅡ | [63] |
| BT | Rf1 | 10 | S12564 Tsp509I-C1361MwoI | Chinsurah BoroⅡ/Koshihikari | IR8 | [65] |
| BT | Rf1 | 10 | M1239Mbol-M66267Xbal | Chinsurah BoroⅡ/Koshihikari | IR8 | [66] |
| BT | Rf1 | 10 | 68923-6-68923-9 | Taichung 65/Chinsurah BoroⅡ | Chinsurah BoroⅡ | [64] |
4.4 其他类型胞质不育恢复基因定位
目前共定位到8个CMS-DA型胞质不育育性恢复QTL,分别位于1、5、9和10号染色体上[67,68,69]（表4）。在1号染色体上定位到3个主效育性恢复QTL,其中,Hu等[69]检测到的育性恢复QTL贡献率最大,为30.2%。在5和9号染色体上分别检测到1个微效和主效育性恢复QTL,其贡献率分别为8.6%和16.0%[68,69]。在10号染色体上定位到3个育性恢复QTL[67,68],其中2个育性恢复QTL qRf10-2和qRf10为主效QTL,其贡献率均大于35%。该研究[67,68]认为植株的育性恢复除受到主效基因的控制外,还受微效基因和环境的影响,恢复基因之间、恢复基因与遗传背景之间、恢复基因与环境之间亦存在着复杂的相互作用。CMS-DA育性恢复QTL主要位于1和10号染色体上,贡献率介于2.9%~43.2%。
表4 水稻其他类型胞质不育育性恢复QTL
Table 4
| 胞质类型 Type of cytoplasm | QTL | 染色体 Chromosome | 区间 Interval | 群体材料 Population | 恢复基因来源 Source of Rf | 参考文献 Reference |
|---|---|---|---|---|---|---|
| DA | qRf1 | 1 | RM1, RG532-RM35 | 协青早A/密阳46 | 密阳46 | [68] |
| DA | qRf1.3 | 1 | RM9-RM3475 | 协青早B//东乡野生稻/协青早B | 东乡野生稻 | [69] |
| DA | qRf1.4 | 1 | RM315-RG236 | 协青早B//东乡野生稻/协青早B | 东乡野生稻 | [69] |
| DA | qRf5 | 5 | RG119-RG474 | 协青早A/密阳46 | 密阳46 | [68] |
| DA | qRf9 | 9 | RM1896-RM201 | 协青早B//协青早B/东乡野生稻 | 东乡野生稻 | [69] |
| DA | qRf10-1 | 10 | RG257-RM311 | 协青早A/密阳46 | 密阳46 | [68] |
| DA | qRf10-2 | 10 | RM258-RZ811 | 协青早A/密阳46 | 密阳46 | [68] |
| DA | qRf10 | 10 | RZ811-RG561 | 协青早A/密阳46 | 密阳46 | [67] |
| ID | Rf(u) | 1 | RM283 | 中9A/R68 | R68 | [70] |
| ID | qRf1.4 | 1 | RM315-RG236 | 协青早B//东乡野生稻/协青早B | 东乡野生稻 | [69] |
| ID | qRf3 | 3 | RM282-RM16 | 协青早B//协青早B/东乡野生稻 | 东乡野生稻 | [69] |
| ID | qRf5.1 | 5 | RM188-RM3870 | 协青早B//协青早B/东乡野生稻 | 东乡野生稻 | [69] |
| ID | qRf5.2 | 5 | RM334-RG119 | 协青早B//协青早B/东乡野生稻 | 东乡野生稻 | [69] |
| ID | qRf7 | 7 | RM481-Indel 7.1 | 协青早B//东乡野生稻/协青早B | 东乡野生稻 | [69] |
| ID | Rf4 | 10 | RM258-RM6100 | 中9A/R68 | R68 | [70] |
| ID | qRf10.1 | 10 | RM1375-RM5620 | 协青早B//东乡野生稻/协青早B | 东乡野生稻 | [69] |
| ID | qRf10.1 | 10 | RM5620-RM1125 | 协青早B//协青早B/东乡野生稻 | 东乡野生稻 | [69] |
| ID | qRf10.2 | 10 | RM171-RM590 | 协青早B//东乡野生稻/协青早B | 东乡野生稻 | [69] |
| LD | Rf2 | 2 | RM12939-RM12955 | Koshihikari/LD-Akihikari | Akihikari | [71] |
| Dian1 | Rf-D1(t) | 10 | OSR33(RM171)-RM228 | Liyu A/Nan 34 | Nan 34 | [72] |
| CW | Rf17 | 4 | RM3866-AT10.5-1 | Taichung 65/中国野生稻W1 | 中国野生稻W1 | [73] |
| FA | Rf(fa) | 10 | MM1967-RM25663 | 金农1A/9311-9 | 9311-9 | [74] |
| FA | Rf(fa) | 10 | RM6100-MM2023 | Acc8558/Jiazao1-6 | Jiazao1-6 | [74] |
| Dissi | Rf | 1 | RM7466-RM1360 | IR75596A/IR68077-82-22-2-3R | IR68077-82-22-2-3R | [49] |
| Dissi | Rf | 10 | RM258-RM6100 | IR75596A/IR68077-82-22-2-3R | IR68077-82-22-2-3R | [49] |
| Gambiaca | Rf | 1 | RM272-RM576 | IR75601A/IR68444R | IR68444R | [49] |
4.5 水稻恢复基因的克隆及其育性恢复机制
表5 已克隆的水稻细胞质不育育性恢复基因
Table 5
| CMS类型 Type of CMS | 染色体 Chromosome | 不育基因 CMS gene | 恢复基因 Rf gene | 核质互作类型 Nuclear-cytoplasm interaction type | 功能 Function | 参考文献 Reference |
|---|---|---|---|---|---|---|
| CMS-WA | 10 | WA352 | Rf4 | 孢子体型 | 降低WA352的表达 | [8,74-75] |
| CMS-HL | 10 | orfH79 | Rf5, Rf6 (PPR) | 配子体型 | 降低atp6的表达 | [57] |
| CMS-BT | 10 | B-orf79 | Rf1a, Rf1b (PPR) | 配子体型 | 降低atp6的表达 | [9,66] |
| ORF11 | Irf1 | 配子体型 | [75] | |||
| CMS-LD | 2 | L-orf79 | Rf2 (GRP) | 配子体型 | 降低atp6的表达 | [71] |
| CMS-CW | 4 | 0rf307 | Rf17 | 配子体型 | RMS启动子区域的SNP变异 逆向信号传导调控其表达水平 | [20,79] |
CMS-HL育性恢复受2个恢复基因Rf5和Rf6的控制[58],且Rf5和Rf6能正常恢复CMS-BT胞质不育[80]。其中,Rf5与CMS-BT的恢复基因Rf1a相似,编码1个PPR蛋白,但Rf5蛋白对atp6-orfH79转录本的加工机制不同。在CMS-BT/Rf1系统中,Rf1a直接结合B-atp6/orf79 mRNA,而在CMS-HL/RF5/RF6系统中,恢复基因Rf5和Rf6不能直接结合不育基因的mRNA。其育性恢复蛋白RF5和RF6需要分别通过招募其他的育性恢复复合体去结合并剪切不育基因mRNA,从而使育性恢复。这些复合体中与恢复基因互作的重要亚基成分包括GRP162、RFC3和OsHXK6。目前相关的互作因子都已被鉴定,并且2个恢复基因都有各自独立的途径来实现不育转录本的加工[57-61,81]。
CMS-BT细胞质中含有线粒体基因atp6,该基因能与一个异常的线粒体开放阅读框orf79共转录编码一个细胞毒素蛋白而导致雄性不育。其育性恢复受Rf1控制,包含2个紧密连锁的恢复基因Rf1a和Rf1b,均编码1个PPR蛋白的多基因簇成员,其中蛋白Rf1A可直接与不育基因转录本B-atp6/orf79的mRNA互作,进而剪接B-atp6/orf79 mRNA恢复育性,而蛋白Rf1B则通过降解B-atp6/orf79的mRNA恢复育性[9]。
全基因组关联研究是分析水稻复杂性状的有效方法之一。对CMS-WA和CMS-HL胞质类型育性恢复相关性状进行全基因组关联分析,分别检测到13和6个显著性位点,其中3个CMS-WA型和2个CMS-HL型育性恢复位点分别与Rf4和Rf6一致;进一步对恢复基因Rf4、Rf5和Rf6进行单倍型分析,表明Rf4、Rf5和Rf6分别有4、2和8个主要单倍型[77]。关联分析与连锁分析相结合可以更有效地挖掘水稻育性恢复相关基因。在克隆的7个水稻育性恢复基因中,水稻CMS-WA、CMS-BT和CMS-HL的恢复机制研究已较为深入,大部分RF编码PPR蛋白,对CMS的调控主要表现在转录或转录后水平。无论以何种机制实现育性恢复,水稻CMS育性恢复的分子机制都有待进一步研究。
5 水稻育性恢复基因的育种利用
水稻细胞质雄性不育及其育性恢复相关基因的发掘与利用极大地促进了我国杂交水稻的大面积推广与应用,对世界水稻增产、粮食安全和社会稳定发挥了重要作用。自20世纪70年代的泰引1号、IR24、IR26和IR661等第1代籼型三系恢复系被测交筛选之后,采用测恢、杂交育种和辐射诱变育种等不同方法,迄今已育成的水稻恢复系不胜枚举,相继出现IR30及其衍生系等第2代三系恢复系,明恢63、桂33、测64-7等第3代三系恢复系,扬稻6号等第4代恢复系两系、三系兼用的共恢恢复系和华占及其衍生系等第5代共恢恢复系[82,83]等不同阶段。其中第3~4代恢复系的测64-7、桂33、明恢63和扬稻6号等代表性恢复系通过“恢复基因转移”选育而成,其主要恢复基因可追溯至IR8、IR30和Peta等东南亚品种,它们是野败型杂交稻前期的主要恢复系以及后续恢复系选育的重要核心种质;而第5代恢复系华占则由马来西亚品种SC02-S6经复测和系统选育而成,说明骨干恢复系在恢复系更替和杂交稻选育中具有重要作用。
华占是近年来在杂交稻育种应用中最广泛的恢复系之一,以引自马来西亚的SC02-S6为亲本材料,通过与不同类型不育系测配选恢和系统选择育成,2008-2017年以华占配组大面积推广的优质组合13个,累计推广373.3万hm2[83]。根据国家水稻数据中心的公开信息（http://www.ricedata.cn/variety/,截止到2020年12月）显示,以华占为父本的杂交组合已有147个通过审定,其中三系组合98个、两系组合49个,多数育成组合具有丰产优质和抗稻瘟病等特性。可见,华占是重要的三系和两系不育系共恢恢复系。由上述分析可见,恢复系是杂交水稻的重要组成部分,杂交水稻组合的更新演替与恢复系的改良与发展密不可分;而恢复基因利用和恢复系的选育是提高杂交水稻抗性与杂种优势的主要推动力。然而,目前我国大面积应用的三系杂交稻组合所使用的不育系主要还是野败型、红莲型和包台型,而生产中推广的籼型不育系的恢复系基本上含有东南亚地区品种或品系的遗传成分,其亲源均可追溯到IR系统、明恢63和测64-7等少数几个优良亲本,导致恢保关系单一,难以实现更进一步的杂种优势,只有发掘新的恢复源才能更进一步提高杂种优势。
6 展望
我国杂交籼稻育种处于世界领先地位,主要得益于在不同类型不育细胞质源及其相应的育性恢复源的发掘利用和优质不育系、恢复系的选育等方面的迅速发展。而水稻育性恢复是由多基因控制的质量-数量性状,其遗传机制十分复杂,不同育性恢复基因之间、恢复基因与遗传背景之间、恢复基因与环境之间存在着复杂的相互作用。得益于分子生物学技术和理论的迅速发展,水稻CMS及其Rf基因相继被克隆和鉴定,丰富了不同胞质类型的不育形成机理和育性恢复机制的认识。此外,育种者可以通过分子标记辅助选择利用已精细定位或克隆的恢复基因,使得恢复系选育过程中恢复位点的选择更加便利[85]。然而,鉴于CMS/Rf系统在作物遗传育种中的重要性,需要研究更多的不同类型水稻CMS/Rf系统并应用于水稻生产实践,以避免遗传脆弱性和同质化现象。因此,就CMS及其Rf的生物学研究和应用应加强如下几点：
6.1 加强三系杂交稻优势的理论基础研究
6.2 加快破解三系杂交稻局限性
6.3 加强水稻远缘杂交研究,提高水稻的杂种优势
远缘杂交产生的水稻杂种优势潜力巨大,以“粳不籼恢”杂交模式育成的籼粳亚种间三系杂交稻取得重要进展。继续加强籼粳杂交的理论和应用研究,以期获得更大突破。广泛开展籼稻、粳稻和热带粳稻等不同类型水稻间的远缘杂交研究,探索新的水稻杂种优势群。
6.4 利用生物信息学技术,助力三系杂交稻育种
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Background: Plant mitochondrial genomes are known for their complexity, and there is abundant evidence demonstrating that this organelle is important for plant sexual reproduction. Cytoplasmic male sterility (CMS) is a phenomenon caused by incompatibility between the nucleus and mitochondria that has been discovered in various plant species. As the exact sequence of steps leading to CMS has not yet been revealed, efforts should be made to elucidate the factors underlying the mechanism of this important trait for crop breeding. Results: Two CMS mitochondrial genomes, LD-CMS, derived from Oryza sativa L. ssp. indica (434,735 bp), and CW-CMS, derived from Oryza rufipogon Griff. (559,045 bp), were newly sequenced in this study. Compared to the previously sequenced Nipponbare (Oryza sativa L. ssp. japonica) mitochondrial genome, the presence of 54 out of 56 protein-encoding genes (including pseudo-genes), 22 tRNA genes (including pseudo-tRNAs), and three rRNA genes was conserved. Two other genes were not present in the CW-CMS mitochondrial genome, and one of them was present as part of the newly identified chimeric ORF, CW-orf307. At least 12 genomic recombination events were predicted between the LD-CMS mitochondrial genome and Nipponbare, and 15 between the CW-CMS genome and Nipponbare, and novel genetic structures were formed by these genomic rearrangements in the two CMS lines. At least one of the genomic rearrangements was completely unique to each CMS line and not present in 69 rice cultivars or 9 accessions of O. rufipogon. Conclusion: Our results demonstrate novel mitochondrial genomic rearrangements that are unique in CMS cytoplasm, and one of the genes that is unique in the CW mitochondrial genome, CW-orf307, appeared to be the candidate most likely responsible for the CW-CMS event. Genomic rearrangements were dynamic in the CMS lines in comparison with those of rice cultivars, suggesting that 'death' and possible 'birth' processes of the CMS genes occurred during the breeding history of rice.
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Rice male sterility cytoplasm and fertility restoration. Hybrid rice:proceedings of the International Symposium on Hybrid Rice
Molecular diversity and multilocus organization of the parental lines used in the international rice molecular breeding program
One hundred and ninety three parental lines obtained from 26 countries for an international rice molecular breeding program were evaluated using 101 well-distributed simple sequence repeat (SSR) markers. An overall genetic diversity of 0.68 and an average of 6.3 alleles per locus were revealed, indicating a high level of genetic variation in these lines. Cluster analysis of the 193 accessions showed three major groups and nine subgroups. Group I corresponded to the classical indica subspecies, whereas groups II and III belong to the japonica subspecies. Indica and japonica differentiation accounted for only 6.5% of the total variation in the entire sample and 93.5% was due to within-subspecies diversity. Differentiation among eco-geographic regions accounted for 24% of the diversity within the subspecies. Larger amounts of the eco-geographical differentiation were resolved within japonica than within indica. The largest indica-japonica differentiation based on the single locus level was detected by markers on chromosomes 9 and 12, while the smallest differentiation was detected by markers on chromosomes 4 and 8. Furthermore, genetic differences at the single-locus and two-locus levels, as well as components due to allelic and gametic differentiation, were revealed between indica and japonica and among the main geographic regions. The multilocus analysis in genetic diversity showed a higher proportion of variation caused by predominant non-random associations of different loci within and among the classified subspecies and geographic subdivisions. The results suggest that selection for eco-geographical adaptation on multilocus associations was largely responsible for the maintenance of the extensive variation in the primary gene pool of rice.
What does the molecular genetics of different types of restorer-of-fertility genes imply
DOI:10.3390/plants9030361 URL [本文引用: 1]
Evolutionary plasticity of restorer-of-fertility-like proteins in rice
DOI:10.1038/srep35152
PMID:27775031
[本文引用: 1]
Hybrid seed production in rice relies on cytoplasmic male sterility (CMS) induced by specific mitochondrial proteins, whose deleterious effects are suppressed by nuclear Restorer of Fertility (RF) genes. The majority of RF proteins belong to a specific clade of the RNA-binding pentatricopeptide repeat protein family. We have characterised 'restorer-of-fertility-like' (RFL) sequences from 13 Oryza genomes and the Brachypodium distachyon genome. The majority of the RFL sequences are found in genomic clusters located at two or three chromosomal loci with only a minor proportion being present as isolated genes. The RFL genomic cluster located on Oryza chromosome 10, the location of almost all known active rice RF genes, shows extreme variation in structure and gene content between species. We show evidence for homologous recombination events as an efficient mechanism for generating the huge repertoire of RNA sequence recognition motifs within RFL proteins and a major driver of RFL sequence evolution. The RFL sequences identified here will improve our understanding of the molecular basis of CMS and fertility restoration in plants and will accelerate the development of new breeding strategies.
Genetics of fertility restoring of wild abortive cytoplasmic male sterility in rice (Oryza sativa L.)
DOI:10.1007/BF00042364 URL [本文引用: 2]
Genetics of fertility restoration in hybrid rice
DOI:10.1007/BF00232962
PMID:24202925
[本文引用: 2]
The cross combination involving 14 male-sterile lines in rice, when crossed with different maintainers, showed fertility restoration in certain combinations. When F2 segregating populations were classified based on spikelet fertility, fertility restoration was shown to be governed by 3∶1, 9∶3∶3∶1, and 12∶3∶1, due to allelic differences. This indicated that the cytosterility of the same group showed monogenic fertility restoration, whereas crossing plants belonging to different cystosterile groups showed a digenic pattern of segregation.
Effects of Rf-1,Rf-3 and Rf-6(t) genes on fertility restoration in rice (Oryza sativa L.) with WA- and BT-type cytoplasmic male sterility
DOI:10.1270/jsbbs.57.223 URL [本文引用: 2]
Genetic analysis of fertility-restorer genes in rice
DOI:10.1007/s10535-008-0092-6 URL [本文引用: 2]
Tagging of four fertility restorer loci for wild abortive-cytoplasmic male sterility system in rice (Oryza sativa L.) using microsatellite markers
DOI:10.1007/s10681-008-9667-8 URL [本文引用: 7]
A cold-inducible modifier QTL affecting fertility restoration of WA CMS in rice
Mapping Rf3 locus in rice by SSR and CAPS markers
Fine mapping of Rf3 and Rf4 fertility restorer loci of WA-CMS of rice (Oryza sativa L.) and validation of the developed marker system for identification of restorer lines
DOI:10.1007/s10681-012-0737-6 URL [本文引用: 5]
Inheritance of the fertility restoration and genotyping of rice lines at the restoring fertility (Rf) loci using molecular markers
Mapping of minor quantitative trait loci (QTLs) conferring fertility restoration of wild abortive cytoplasmic male sterility and QTLs conferring stigma exsertion in rice
DOI:10.1111/pbr.2014.133.issue-6 URL [本文引用: 8]
Comparative genetic analysis and molecular mapping of fertility restoration genes for WA,Dissi,and Gambiaca cytoplasmic male sterility systems in rice
DOI:10.1007/s10681-007-9498-z URL [本文引用: 10]
Marker-assisted identification of restorer gene(s) in iso-cytoplasmic restorer lines of WA cytoplasm in rice and assessment of their fertility restoration potential across environments
DOI:10.1007/s12298-017-0464-5 URL [本文引用: 2]
Mapping fertility-restoring genes of rice WA cytoplasmic male sterility using SSLP markers
Molecular mapping of a gene for fertility restoration of wild abortive (WA) cytoplasmic male sterility using a basmati rice restorer line
DOI:10.1007/BF03263157 URL [本文引用: 2]
Vaildation of molecular markers linked to fertility restorer gene(s) for WA-CMS lines of rice
DOI:10.1007/s10681-008-9865-4 URL [本文引用: 2]
Molecular mapping of the fertility-restoration gene Rf4 for WA-cytoplasmic malesterility in rice
DOI:10.1111/pbr.2006.125.issue-4 URL [本文引用: 3]
Genic markers for wild abortive (WA) cytoplasm based male sterility and its fertility restoration in rice
DOI:10.1007/s11032-010-9397-1 URL [本文引用: 4]
The rice pentatricopeptide repeat Protein RF5 restores fertility in Hong-Lian cytoplasmic male-sterile lines via a complex withthe glycine-rich protein GRP162
DOI:10.1105/tpc.111.093211 URL [本文引用: 6]
Fine mapping of the nuclear fertility restorer gene for HL cytoplasmic male sterility in rice
Two non-allelic nuclear genes restore fertility in a gametophytic pattern and enhance abiotic stress tolerance in the hybrid rice plant
DOI:10.1007/s00122-011-1755-9 URL [本文引用: 4]
Pentatricopeptide-repeat family protein RF6 functions with hexokinase 6 to rescue rice cytoplasmic male sterility
Inheritance and molecular mapping of two fertility-restoring loci for Honglian gametophytic cytoplasmic male sterility in rice
The Honglian cytoplasmic male sterility ( cms-HL) system, a novel type of gametophytic CMS in indica rice, is being used for the large-scale commercial production of hybrid rice in China. However, the genetic basis of fertility restoration ( Rf) in cms-HL remains unknown. Previous studies have shown that fertility restoration is controlled by a single locus located on chromosome 10, close to the loci Rf1 and Rf4, which respond to cms-BT and cms-WA, respectively. To determine if the Rf locus for cms-HL is different from these Rf loci and to establish fine-scale genetic and physical maps for map-based cloning of the Rf gene, high-resolution mapping of the Rf gene was carried out using RAPD and microsatellite markers in three BCF(1) populations. The results of the genetic linkage analysis indicated that two Rf loci respond to cms-HL, and that these are located in different regions of chromosome 10. One of these loci, Rf5, co-segregates with the SSR marker RM3150, and is flanked by RM1108 and RM5373, which are 0.9 cM and 1.3 cM away, respectively. Another Rf locus, designated as Rf6(t), co-segregates with RM5373, and is flanked by RM6737 and SBD07 at genetic distances of 0.4 cM. The results also demonstrated these loci are distinct from Rf1 and Rf4. A 105-kb BAC clone covering the Rf6(t) locus was obtained from a rice BAC library. The sequence of a 66-kb segment spanning the Rf6(t) locus was determined by a BLASTX search in the genomic sequence database established for the cultivar 93-11.
Linkage analysis of a fertility restoring mutant generated from CMS rice
DOI:10.1007/s001220050894 URL [本文引用: 3]
A codominant DNA marker closely linked to the rice nuclear restorer gene,Rf-1,identified with inter-SSR fingerprinting
A new molecular marker (OSRRf) closely linked to the nuclear restorer gene (Rf-1) for fertility in rice has been found. The Rf-1 gene is essential for hybrid rice seed production. A PCR-fingerprinting technique using simple sequence repeats (SSRs) was applied to compare two near-isogenic lines with (MTC-10R) or without (MTC-10A) the Rf-1 gene. Of 76 inter-SSR primers tested, only one primer, (AG)8YC, generated polymorphisms. The tetranucleotide repeats generating polymorphisms were found within each amplicon. the genetic distance between OSRRf and Rf-1 was 3.7 +/- 1.1 cM. As in the case of a codominant marker, this marker will be applied not only to breeding both restorer lines and maintainer lines, but also to the purity management of hybrid rice seeds.
Positional cloning of the rice Rf-1 gene,a restorer of BT-type cytoplasmic male sterility that encodes a mitochondria-targeting PPR protein
The combination of cytoplasmic male sterility (CMS) in one parent and a restorer gene ( Rf) to restore fertility in another are indispensable for the development of hybrid varieties. We have found a rice Rf-1 gene that restores BT-type CMS by applying a positional cloning strategy. Using linkage analysis in combination with 6,104 BC(1)F(3) progeny derived from a cross between two near-isogenic lines (NILs) differing only at the Rf-1 locus, we delimited the Rf-1 gene to a 22.4-kb region in the rice genome. Duplicate open reading frames ( Rf-1A and Rf-1B) with a pentatricopeptide (PPR) motif were found in this region. Since several insertions and/or deletions were found in the regions corresponding to both the Rf-1A and Rf-1B genes in the maintainer's allele, they may have lost their function. Rf-1A protein had a mitochondria-targeting signal, whereas Rf-1B did not. The Rf-1B gene encoded a shorter polypeptide that was determined by a premature stop codon. Based on the function of the Rf-1 gene, its product is expected to target mitochondria and may process the transcript from an atp6/orf79 region in the mitochondrial genome. Since the Rf-1A gene encodes a 791-amino acid protein with a signal targeting mitochondria and has 16 repeats of the PPR motif, we concluded that Rf-1A is the Rf-1 gene. Nine duplications of Rf-1A homologs were found around the Rf-1 locus in the Nipponbare genome. However, while some of them encoded proteins with the PPR motif, they do not restore BT-type CMS based on the lack of co-segregation with the restoration phenotype. These duplicates may have played diversified roles in RNA processing and/or recombination in mitochondria during the co-evolution of these genes and the mitochondrial genome.
Fine genetic mapping of the nuclear gene Rf-1,that restores the BT-type cytoplasmic male sterility in rice (Oryza sativa L.) by PCR-based markers
DOI:10.1023/A:1021915611210 URL [本文引用: 2]
Map-based cloning of a fertility restorer gene,Rf-1,in rice (Oryza sativa L.)
DOI:10.1046/j.1365-313X.2003.01961.x URL [本文引用: 4]
Mapping QTLs for fertility restoration of different cytoplasmic male sterility types in rice using two Oryza sativa ×O. rufipogon backcross inbred line populations
The fertility restorer gene,Rf2,for Lead-Rice type cytoplasmic male sterility of rice encodes a mitochondrial glycine-rich protein
DOI:10.1111/j.1365-313X.2010.04427.x
PMID:21265890
[本文引用: 6]
Cytoplasmic male sterility (CMS) is associated with a mitochondrial mutation that causes an inability to produce fertile pollen. The fertility of CMS plants is restored in the presence of a nuclear-encoded fertility restorer (Rf) gene. In Lead Rice-type CMS, discovered in the indica variety 'Lead Rice', fertility of the CMS plant is restored by the single nuclear-encoded gene Rf2 in a gametophytic manner. We performed map-based cloning of Rf2, and proved that it encodes a protein consisting of 152 amino acids with a glycine-rich domain. Expression of Rf2 mRNA was detected in developing and mature anthers. An RF2-GFP fusion was shown to be targeted to mitochondria. Replacement of isoleucine by threonine at amino acid 78 of the RF2 protein was considered to be the cause of functional loss in the rf2 allele. As Rf2 does not encode a pentatricopeptide repeat protein, unlike a majority of previously identified Rf genes, the data from this study provide new insights into the mechanism for restoring fertility in CMS.© 2010 The Authors. The Plant Journal © 2010 Blackwell Publishing Ltd.
Identification of the Rf gene conferring fertility restoration of the CMS Dian-type 1 in rice by using simple sequence repeat markers and advanced inbred lines of restorer and maintainer
DOI:10.1111/pbr.2004.123.issue-4 URL [本文引用: 1]
Molecular mapping of the fertility restorer gene for ms-CW-type cytoplasmic male sterility of rice
Cytoplasmic male sterility (CMS) of rice (Oryza sativa L.) was first reported using the cytoplasm of a Chinese wild rice, Oryza rufipogon Griff. strain W1. However, it was not possible to characterize this ms-CW-type CMS in more detail until a restorer line had been developed due to the lack of restorer genes among cultivars thus far tested. The breeding of a restorer line (W1-R) was eventually achieved by transferring the restorer gene(s) of W1 to a cultivar. We report here the characterization of the ms-CW pollen grains and mapping of the restorer gene for ms-CW-type CMS. Pollen grains of the male-sterile plants appeared to be normal and viable based on the fluorochromatic reaction test, but they did not germinate on normal stigmas. The 1:1 segregation of fertile and sterile plants in a BC(1)F(1) population from a cross between W1-R and a maintainer line demonstrated that fertility restoration is controlled by a single gene. The fertile seed set of all the F(2) plants examined indicated that the fertility restoration functions gametophytically. We designated the fertility restorer gene Rfcw. Using cleaved amplified polymorphic sequence (CAPS) and simple sequence repeat (SSR) markers, we localized Rfcw to chromosome 4 with a genetic distance of 0.6 cM from the nearest SSR marker.
Fine mapping of a fertility restoring gene for a new CMS hybrid rice system
DOI:10.1007/s11032-016-0561-0 URL [本文引用: 6]
Fertility restoration by Ifr1 in rice with BT-type cytoplasmic male sterility is associated with a reduced level,but not processing,of atp6-orf79 cotranscribed RNA
DOI:10.1007/s00299-010-0827-7 URL [本文引用: 3]
The rice restorer Rf4 for wild-abortive cytoplasmic male sterility encodes a mitochondrial-localized PPR protein that functions in reduction of WA352 transcripts
DOI:10.1093/mp/ssu047 URL [本文引用: 1]
A fertility restorer gene,Rf4,widely used for hybrid rice breeding encodes a pentatricopeptide repeat protein
DOI:10.1186/s12284-014-0028-z URL [本文引用: 2]
Genome-wide association studies reveal the genetic basis of fertility restoration of CMS-WA and CMS-HL in xian/indica and aus accessions of rice (Oryza sativa L.)
DOI:10.1186/s12284-020-0372-0 URL [本文引用: 1]
Fertility restoration of Chinese wild rice-type cytoplasmic male sterility by CRISPR/Cas9-mediated genome editing of nuclear-encoded retrograde-regulated male sterility
DOI:10.5511/plantbiotechnology.20.0326b URL [本文引用: 3]
Ability of Rf5 and Rf6 to restore fertility of Chinsurah Boro II-type cytoplasmic male sterile Oryza sativa (ssp. Japonica) lines
DOI:10.1186/s12284-017-0142-9 URL [本文引用: 1]
The rice DUF1620-containing and WD40-like repeat protein is required for the assembly of the restoration of fertility complex
DOI:10.1111/nph.2016.210.issue-3 URL [本文引用: 1]
Significant association of the novel Rf4-targeted SNP marker with restorer for WA-CMS in different rice backgrounds and its utilization in molecular screening
DOI:10.1016/S2095-3119(16)61620-9 URL [本文引用: 3]
Development of cytoplasmic male sterile lines and restorer lines of various elite indica group rice cultivars using CW-CMS/Rf17 system
DOI:10.1186/s12284-019-0332-8
PMID:31535306
[本文引用: 1]
A cytoplasm of CW-type cytoplasmic male sterile (CMS) line is derived from Oryza rufipogon strain W1 and fertility is restored by a single nuclear gene, Rf17. We have previously reported that CW-CMS were effective for breeding CMS lines of Indica Group rice cultivars, IR 24 and IR 64. The applicability of this CW-CMS/Rf17 system to produce other elite Indica Group rice cultivars with CMS was explored.Out of seven elite Indica Group rice cultivars, complete CMS lines were obtained for six cultivars: NSIC Rc 160, NSIC Rc 240, Ciherang, BRRI dhan 29, NERICA-L-19, and Pusa Basmati. The fertility of these six lines was restored when Rf17 was present. A CMS line was not obtained for the cultivar Samba Mahsuri.The CW-CMS/Rf17 system will be useful to produce CMS lines and restorer lines of various elite Indica Group rice cultivars.
Development of high yield glutinous cytoplasmic male sterile rice (Oryza sativa L.) lines through CRISPR/Cas9 based mutagenesis of Wx and TGW6 and proteomic analysis of anther
DOI:10.3390/agronomy8120290 URL [本文引用: 1]
