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91.
The application of the mutated acetolactate synthase gene from rice as the selectable marker gene in the production of transgenic soybeans 总被引:1,自引:0,他引:1
Makoto Tougou Noriko Yamagishi Noriyuki Furutani Koichiro Kaku Tsutomu Shimizu Yoshihito Takahata Jun-ichi Sakai Seiji Kanematsu Soh Hidaka 《Plant cell reports》2009,28(5):769-776
We investigated selective culturing conditions for the production of transgenic soybeans. In this culturing system, we used
the acetolactate synthase (ALS)-inhibiting herbicide-resistance gene derived from rice (Os-mALS gene) as a selectable marker gene instead of that derived from bacteria, which interfered with the cultivation and practical
usage of transgenic crops. T1 soybeans grown from one regenerated plant after selection of the ALS-targeting pyrimidinyl carboxy (PC) herbicide bispyribac-sodium
(BS) exhibited herbicide resistance, and the introduction and expression of the Os-mALS gene were confirmed by genetic analysis. The selective culturing system promoted by BS herbicide, in which the Os-mALS gene was used as a selectable marker, was proved to be applicable to the production of transgenic soybeans, despite the appearance
of escaped soybean plants that did not contain the Os-mALS transgene. 相似文献
92.
Identification of quantitative trait loci controlling rice mature seed culturability using chromosomal segment substitution lines 总被引:1,自引:0,他引:1
Lina Zhao Hongju Zhou Liaoxun Lu Li Liu Xianghua Li Yongjun Lin Sibin Yu 《Plant cell reports》2009,28(2):247-256
The genetic transformation efficiency of a rice variety is largely determined by its tissue culturability. Establishment of
a highly efficient tissue-culture system has greatly accelerated the wide spread application of transgenic japonica varieties. However, such process for indica rice was hampered because this type of variety is recalcitrant to in vitro culture. This study aimed to map the quantitative
trait loci (QTLs) for mature seed culturability using a chromosomal segment substitution lines (CSSL) population derived from
a cross between an indica variety “Zhenshan 97B” and a japonica variety “Nipponbare”. The CSSLs consist of 139 lines each containing a single or a few introgression segments, and together
covering the whole “Nipponbare” genome. Every CSSL was tested by culturing on the two medium systems developed for the respective
indica and japonica parental varieties. The performance of culturability was evaluated by four indices: frequency of callus induction (CIF),
callus subculture capability (CSC), frequency of plant regeneration (PRF) and the mean plantlet number per regenerated callus
(MNR). All four traits displayed continuous variation among the CSSLs. With the culture system for japonica rice, three CIF QTLs, three CSC QTLs, three PRF QTLs and three MNR QTLs were detected. With the culture system for indica variety, six CIF QTLs, two CSC QTLs, three PRF QTLs and six MNR QTLs were identified, and these QTLs distributed on nine
rice chromosomes. Two QTLs of CIF and two QTLs of MNR were detected in both the japonica and indica rice culture system. The correlation coefficients of all the four traits varied depending on the culture systems. These results
provide the possibilities of enhancing the culturability of indica rice by marker-assisted breeding with those desirable alleles from the japonica.
Lina Zhao and Hongju Zhou have contributed equally to this work. 相似文献
93.
Xinshu Zhuang Zhenhong Yuan Longlong Ma Chuangzhi Wu Mingzhong Xu Jingliang Xu Shunni Zhu Wei Qi 《Biotechnology advances》2009,27(5):578
We investigated the kinetics of hot liquid water (HLW) hydrolysis over a 60-min period using a self-designed setup. The reaction was performed within the range 160–220 °C, under reaction conditions of 4.0 MPa, a 1:20 solid:liquid ratio (g/mL), at 500 rpm stirring speed. Xylan was chosen as a model compound for hemicelluloses, and two kinds of agricultural wastes–rice straw and palm shell–were used as typical feedstocks representative of herbaceous and woody biomasses, respectively. The hydrolysis reactions for the three kinds of materials followed a first-order sequential kinetic model, and the hydrolysis activation energies were 65.58 kJ/mol for xylan, 68.76 kJ/mol for rice straw, and 95.19 kJ/mol for palm shell. The activation energies of sugar degradation were 147.21 kJ/mol for xylan, 47.08 kJ/mol for rice straw and 79.74 kJ/mol for palm shell. These differences may be due to differences in the composition and construction of the three kinds of materials. In order to reduce the decomposition of sugars, the hydrolysis time of biomasses such as rice straw and palm shell should be strictly controlled. 相似文献
94.
Plants are attractive expression systems for the economic production of recombinant proteins. Among the different plant-based systems, plant seed is the leading platform and holds several advantages such as high protein yields and stable storage of target proteins. Significant advances in using seeds as bioreactors have occurred in the past decade, which include the first commercialized plant-derived recombinant protein. Here we review the current progress on seeds as bioreactors, with focus on the different food crops as production platforms and comprehensive strategies in optimizing recombinant protein production in seeds. 相似文献
95.
A. N. G. Dabul H. Belefant-Miller M. RoyChowdhury J. F. Hubstenberger A. Lorence G. C. Phillips 《In vitro cellular & developmental biology. Plant》2009,45(4):414-420
Rice has emerged as a model monocot for studies in agriculture and biotechnology due to its relatively small genome and a
ready accessibility to plant material. Tissue culture is one of the tools required for genetic transformation and some breeding
programs, and the selection of high-frequency regenerator types is essential for success in these technologies. Thirty-three
rice entries with agricultural and biotechnological characteristics of interest were screened with the aim to identify the
best regenerators. Entries that exhibited between 50% and 90% regeneration frequencies include ‘Taipei-309,’ ‘Super Dwarf,’
‘Norin’ (japonica types), PI 312777, ‘Ali Combo’ (indica types), ‘STG-S,’ and ‘LA3’ (red rice types). One third of the entries
tested were at least two times better at regeneration than the often-cited regenerator ‘Nipponbare.’ Those entries showing
at least 85% frequency of greening or somatic embryo formation at 15 or 30 d on regeneration medium ultimately produced whole
plants after 45 d on regeneration medium at high frequency (at least 40%); those entries not reaching the 85% threshold of
greening by Days 15 or 30 exhibited moderate (15–40%) to low (less than 10%) frequency of whole plant regeneration. This greening
response suggests the means for an early prediction system for identification of useful rice regenerator lines, which would
be beneficial for high-throughput screening of germplasm as well as for decreasing the time and cost of in vitro culture. 相似文献
96.
97.
Hui Li Jing Yang Yayu Wang Zhijun Chen Sansi Tu Lingling Feng Yingguo Zhu Yangsheng Li 《Biotechnology letters》2009,31(6):905-910
A novel OSPGYRP gene encoding a rice proline-, glycine- and tyrosine-rich protein was isolated from cold-stress treated rice seedlings using
suppression subtractive hybridization. Both amino acid sequence analysis and subcellular localization confirm that OsPGYRP
is a novel protein involved in vesicle trafficking. The expression of the OSPGYRP gene was induced by cold, salt, and osmotic stress. In addition, expression of the OSPGYRP gene in E. coli increased the resistance to cold stress. These results show that OsPGYRP is a novel protein involved in vesicle trafficking
and plays an important role in plant adaptation to stress.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
98.
Yamasaki Masanori Yoshimura Atsushi Yasui Hideshi 《Molecular breeding : new strategies in plant improvement》2003,12(2):133-143
Rice (Oryza sativa L.) ovicidal response to the whitebacked planthopper (Sogatella furcifera Horváth) is characterized by formation of watery lesions and production of an ovicidal substance benzyl benzoate, which results in high egg mortality of whitebacked planthopper. A gene with ovicidal activity to whitebacked planthopper, designated Ovc, and four ovicidal quantitative trait loci (QTLs), qOVA-1-3, qOVA-4, qOVA-5-1 and qOVA-5-2 were identified using near isogenic lines with reciprocal genetic backgrounds of a non-ovicidal Indica variety IR24 and an ovicidal Japonica variety Asominori. Ovc and the four QTLs were mapped on chromosomes 6, 1, 4, 5 and 5, respectively. Ovc is the first gene identified that kills insect eggs in plants. The Asominori allele at Ovc was essential for increasing egg mortality and responsible for production of benzyl benzoate and formation of watery lesions. The Asominori alleles at qOVA-1-3, qOVA-5-1 and qOVA-5-2 increased egg mortality in the presence of Ovc. In contrast, the Asominori allele at qOVA-4 suppressed egg mortality, indicating that qOVA-4 caused transgressive segregation for egg mortality. It was concluded that Ovc and four ovicidal QTLs accounted for the majority of the phenotypic variance for the ovicidal response to whitebacked planthopper in Asominori. 相似文献
99.
100.
不同环境下水稻谷粒重发育的杂种优势和遗传相关性分析 总被引:12,自引:4,他引:8
选用9个不同类型的水稻品种(系),按双列杂交设计(6×5)配成两套亲本和F12个世代的遗传材料,采用数量性状的加性、显性遗传模型、发育遗传模型比较分析了水稻谷粒重发育的杂种优势和遗传相关性。结果表明,早季在谷粒充实前期(1~12d)群体平均优势较小,中后期(13~28d)正向优势趋于明显,在谷粒充实的全过程均表现较小的负向群体超亲优势;晚季则在谷粒充实前中期(1~18d)表现正向群体平均优势。后期(19~28d)优势不明显,在谷粒充实前期(1~12d)表现正向群体超亲优势,之后转为明显的负向群体超亲优势,表明晚季谷粒发育的杂种优势表现较之早季更有利于提高籽粒充实质量,不同发育时期谷粒重之间以及与最终谷粒重之间的遗传相关分析表明,早季以显性相关为主,晚季以加性相关为主,随着发育进程的推进,相关趋于密切。 相似文献