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961.
Brassinosteroids promote development of rice pollen grains and seeds by triggering expression of Carbon Starved Anther,a MYB domain protein 总被引:2,自引:0,他引:2 下载免费PDF全文
Xiaolei Zhu Wanqi Liang Xiao Cui Mingjiao Chen Changsong Yin Zhijing Luo Jiaying Zhu William J. Lucas Zhiyong Wang Dabing Zhang 《The Plant journal : for cell and molecular biology》2015,82(4):570-581
Transport of photoassimilates from leaf tissues (source regions) to the sink organs is essential for plant development. Here, we show that a phytohormone, the brassinosteroids (BRs) promotes pollen and seed development in rice by directly promoting expression of Carbon Starved Anther (CSA) which encodes a MYB domain protein. Over‐expression of the BR‐synthesis gene D11 or a BR‐signaling factor OsBZR1 results in higher sugar accumulation in developing anthers and seeds, as well as higher grain yield compared with control non‐transgenic plants. Conversely, knockdown of D11 or OsBZR1 expression causes defective pollen maturation and reduced seed size and weight, with less accumulation of starch in comparison with the control. Mechanically, OsBZR1 directly promotes CSA expression and CSA directly triggers expression of sugar partitioning and metabolic genes during pollen and seed development. These findings provide insight into how BRs enhance plant reproduction and grain yield in an important agricultural crop. 相似文献
962.
HLA class I and class II expression was analyzed weekly by cytofluorometry on spermatozoa samples from four donors during a 15-wk trial. On the same day that semen samples were studied, and to analyze whether this expression was hormone-controlled, serum levels of testosterone, LH, FSH, inhibin B, activin, and pro-alphaC on the one hand, and seminal plasma levels of inhibin B, activin, and alpha-inhibin on the other, were also measured. Inhibin B and related peptides were quantitated using a novel two-site assay with monoclonal antibodies to the alpha and beta subunits of inhibin. Our results showed that HLA class I and class II molecules were expressed on the spermatozoa's surface, following a cyclic pattern, and that there was a simultaneous and coordinated expression of both types of molecules (r = 0.801, P < 0.0001). Furthermore, when the expression of these molecules was plotted against the different hormone levels, serum inhibin B showed a clear inverse correlation with HLA class I (r = -0.612, P < 0.0001) and class II (r = -0.534, P < 0.0001). This finding reveals unexpected functions of inhibin B, which may be relevant in the fertilization process and on male fertility control. 相似文献
963.
Liu Xi Ding Li Yuan Jing Liao Jian Duan Lian Wang Wenfei Tan Weiguo Yu Weiye Zhou Boping Chen Xinchun Yang Zheng 《中国病毒学》2019,34(3):334-337
<正>Dear Editor,H7 N9 is a recently identified subtype of influenza A virus that caused a major outbreak in humans in China in 2013.According to the latest data provided by the Chinese Center for Disease Control and Prevention(http://www.moh.gov.cn/zwgk/yqbb3/ejlist.shtml, updated on October 31, 2018),the mortality rate of H7 N9 infections in China amounts to 相似文献
964.
Q Chen M Chopp M O Dereski B C Wilson M S Patterson A Schreiber F W Hetzel 《Radiation research》1992,132(1):120-123
This paper reports the effect of incident light fluence rate on the depth to which necrotic lesions are produced by photodynamic therapy (PDT) in the brains of normal Fisher rats. The rats were injected intraperitoneally with Photofrin (12.5 mg kg-1) 48 h prior to PDT with a fixed incident fluence of 35 J cm-2. The treatment was performed at 10, 50, 100, and 200 mW cm-2 and also in a periodic manner (30 s "on" at 100 mW cm-2, 30 s "off"). The depth to which necrosis occurred was determined 24 h after treatment by microscopic examination of tissue sections. No differences were found in the depth to which necrosis was produced by any of the five irradiation schedules. This finding is discussed in the context of other published dose-rate experiments. 相似文献
965.
Ranyue Ren Jiachao Guo Yangmengfan Chen Yayun Zhang Liangxi Chen Wei Xiong 《Cell proliferation》2021,54(11)
The bone remodelling process is closely related to bone health. Osteoblasts and osteoclasts participate in the bone remodelling process under the regulation of various factors inside and outside. Excessive activation of osteoclasts or lack of function of osteoblasts will cause occurrence and development of multiple bone‐related diseases. Ca2+/Calcineurin/NFAT signalling pathway regulates the growth and development of many types of cells, such as cardiomyocyte differentiation, angiogenesis, chondrogenesis, myogenesis, bone development and regeneration, etc. Some evidences indicate that this signalling pathway plays an extremely important role in bone formation and bone pathophysiologic changes. This review discusses the role of Ca2+/Calcineurin/NFAT signalling pathway in the process of osteogenic differentiation, as well as the influence of regulating each component in this signalling pathway on the differentiation and function of osteoblasts, whereby the relationship between Ca2+/Calcineurin/NFAT signalling pathway and osteoblastogenesis could be deeper understood. 相似文献
966.
Chia-Cheng Hung Shee-Uan Chen Shin-Yu Lin Mei-Ya Fang Yi-Yi Tsai Yu-Shih Yang Yi-Ning Su 《Analytical biochemistry》2010,400(1):69-77
Preimplantation genetic diagnosis (PGD) is employed increasingly to allow transfer of embryos to the uterus in assisted reproduction procedures. There are three stages of biopsy: polar bodies, one or two blastomeres from the cleavage-stage embryos, and trophectoderm cells (∼5 cells) from the blastocyst-stage embryos. Validation of polymerase chain reaction (PCR)-based assays are challenging because only limited genetic material can be obtained for PGD. In the current study, we modified a valid single-cell PCR protocol for PGD using real-time PCR assay with fluorescence resonance energy transfer (FRET) hybridization probes followed by melting curve analysis. We optimized and clinically applied the protocol, permitting molecular genetic analysis to amplify a specific region on the beta-globin (HBB) gene for a couple, carriers of two mutations: c.-78A>G and c.52A>T. Among a total of eight embryos obtained after ovarian stimulation, a single blastomere per embryo at the six- to eight-cell stage was biopsied. This PGD method showed that four embryos were unaffected, two embryos were selected for transfer, and one pregnancy was achieved. Finally, a healthy male baby was delivered at 38 weeks’ gestation. The results obtained using the new method, FRET hybridization probes, were compared with findings using an existing method, primer extension minisequencing. 相似文献
967.
968.
Zhong Q Zhang Q Wang Z Qi J Chen Y Li S Sun Y Li C Lan X 《Marine biotechnology (New York, N.Y.)》2008,10(3):310-318
Differential expression of genes is crucial to embryogenesis. The analysis of gene expression requires appropriate references
that should be minimally regulated during the embryonic development. To select the most stable genes for gene normalization,
the expression profiles of eight commonly used reference genes (ACTB, GAPDH, rpL17, α-Tub, EF1-α, UbcE, B2M, and 18S rRNA)
were examined during Japanese flounder (Paralichthys olivaceus) embryonic development using quantitative real-time polymerase chain reaction. It was found that all seven mRNA genes appeared
to be developmentally regulated and exhibited significant variation of expression. However, further analyses revealed the
stage-specific expression stability. Hence when normalization using these mRNA genes, the differential and stage-related expression
should be considered. 18S rRNA gene, on the other hand, showed the most stable expression and could be recommended as a suitable
reference gene during all embryonic developmental stages in P. olivaceus. In summary, our results provided not only the appropriate reference gene for embryonic development research in P. olivaceus, but also possible guidance to reference gene selection for embryonic gene expression analyses in other fish species. 相似文献
969.
Wenying Shou Ramzi Azzam Susan L Chen Michael J Huddleston Christopher Baskerville Harry Charbonneau Roland S Annan Steve A Carr Raymond J Deshaies 《BMC molecular biology》2002,3(1):3-14
Background
In S. cerevisiae, the mitotic exit network (MEN) proteins, including the Polo-like protein kinase Cdc5 and the protein phosphatase Cdc14, are required for exit from mitosis. In pre-anaphase cells, Cdc14 is sequestered to the nucleolus by Net1 as a part of the RENT complex. When cells are primed to exit mitosis, the RENT complex is disassembled and Cdc14 is released from the nucleolus. 相似文献970.
S S Chen J W Bohn F T Liu D H Katz 《Journal of immunology (Baltimore, Md. : 1950)》1981,127(1):166-173