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31.
Yihao Yang Ziyan Shen Youguang Li Chenda Xu Han Xia Hao Zhuang Shengyuan Sun Min Guo Changjie Yan 《植物学报(英文版)》2022,64(10):1860-1865
Rice eating and cooking quality (ECQ) is a major concern of breeders and consumers, determining market competitiveness worldwide. Rice grain protein content (GPC) is negatively related to ECQ, making it possible to improve ECQ by manipulating GPC. However, GPC is genetically complex and sensitive to environmental conditions; therefore, little progress has been made in traditional breeding for ECQ. Here, we report that CRISPR/Cas9-mediated knockout of genes encoding the grain storage protein glutelin rapidly produced lines with downregulated GPC and improved ECQ. Our finding provides a new strategy for improving rice ECQ. 相似文献
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36.
Yan-Hong He Guo-Gui Ning Ya-Lin Sun Yan Hu Xing-Yu Zhao Man-Zhu Bao 《Molecular breeding : new strategies in plant improvement》2010,26(1):19-29
A male sterile line was isolated in marigold (Tagetes erecta L.) and cytological analysis determined this to be a novel genic male sterility trait (Tems). Through the use of amplified fragment length polymorphisms (AFLPs) and bulked segregant analysis (BSA), tightly linked
markers of Tems were identified with a view towards a map-based cloning strategy. It was found that spontaneous homeotic conversion of floral
organs was the underlying cause of the male sterility in this marigold line. Thus, petals of male sterile plants resembled
sepal-like structures and the stamens were partially converted to styles, although without the full characteristics or function
of the true style organs. We have constructed a fine marker-based map for the Tems gene. This is intended to provide a tool for marker assisted selection (MAS) strategies in hybrid breeding and map-based
cloning strategies for the male sterility locus. We discuss the significance of this spontaneously derived genic male sterility
trait relating to the homeotic conversion of floral organs in marigold. 相似文献
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Abstract Rheocricotopus (Psilocricotopus) taiwanensis sp. n. from Taiwan, China, is described as male imagines. The species is allied to R. (P.) chalybeatus (Edwards) but it is easily separated from the latter in lacking setae in all reins, much lower AR and more pronounced crista dorsalis in gonostylus. The genus is new to Taiwan Province, China. The specimen is deposited at the Department of Biology, Nankai University, Tianjin. 相似文献
39.
Yan Yongshan Fen Shang Liu Lianrui 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,74(1):147-153
Summary A 8.3 /ml 6-thioguanine (6TG)-resistant strain was isolated from a rat tetraploid cell line by step-by-step selection in 6TG-medium. In the 6TG-resistant cell population 51% of the cells were tetraploid and 35% of the cells were hypertetraploid, i.e., one chromosome more than a tetraploid. The 6TG-resistant strain grew very well in RPMI 1640 medium with intervals of three days between subcultures. The 6TG-resistant cells all have a homogeneously staining region (HSRs) in one of the X chromosomes which do not stain after chromosome C-banding. They also possess a higher NORs activity and much lower frequency of sister chromatid exchanges (SCE). When the 6TG-resistant RCT cells were subcultured in 6TG-free medium for three days, their SCE frequency did not change. 5-bromodeoxyuridine (BrdU) significantly suppressed the NORs activity for both 6TG-resistant cells and 6TG-sensitive cells (P<0.001).Abbreviations 6TG
6-thioguanine
- HSRs
homogeneously staining region
- NORs
nucleolar organizer region
- SCE
sister chromatid exchange
- BrdU
5-bromodeoxyuridine
- HPRT
Hypoxanthine phosphoribosyl transferase 相似文献
40.
H D S?ling E Machado-DeDomenech J Kleineke W Fest 《The Journal of biological chemistry》1987,262(35):16786-16792
The early effects (0-120 s) of the beta-adrenergic secretagogue isoproterenol (2.10(-5) M) and the muscarinic secretagogue carbamoylcholine (2.10(-6) M) on various parameters of lipid and phospholipid metabolism were studied in isolated guinea pig parotid acinar cells. Both agonists enhanced within 10-20 s the incorporation of radioactive palmitate into the diacylglycerol, the triglyceride, and the phosphatidylinositol fractions but significantly diminished radioactive palmitate recovered in the acyl-CoA fraction. Carbamoylcholine decreased and isoproterenol increased the recovery of radioactive palmitate in the free fatty acid fraction. All changes had returned almost to control levels after 120 s. In cells prelabeled with [3H]arachidonate, carbamoylcholine exerted similar effects, whereas isoproterenol was almost ineffective. Both agonists stimulated the incorporation of radioactive glycerol into diacylglycerols 2-3-fold, while only carbamoylcholine stimulated the incorporation of [32P]phosphate into phosphatidylinositol and phosphatidate. Both agonists induced an increase in total diacylglycerols, carbamoylcholine being about twice as effective as isoproterenol. A lower concentration of carbamoylcholine (6.5.10(-7) M) had the same quantitative effect as 2.10(-5) M isoproterenol on the increase of total diacylglycerols. Even under these conditions carbamoylcholine, but not isoproterenol led to a significant translocation of protein kinase C from the soluble to the particulate fraction. Isoproterenol remained ineffective in this respect also when intracellular free calcium was increased with a calcium ionophore. This is explained by the finding that isoproterenol stimulates preferentially the formation of 2,3-sn-diacylglycerol, and carbamoylcholine preferentially stimulates the formation of 1,2-sn-diacylglycerol. The results indicate that in the guinea pig parotid acinar cell the two agonists do not only lead to activation of a triglyceride lipase (isoproterenol) or phosphoinositide-specific phospholipase(s) (carbamoylcholine), but also to a rapid change of flux through a number of other enzyme-catalyzed reactions involved in diacylglycerol turnover. 相似文献