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21.
Tomohiro Teraminami Atsushi Nakashima Mao Ominami Masanori Yamamoto Zhang Guo Sheng Ken Yoshikawa 《Landscape and Ecological Engineering》2013,9(2):249-257
Salix cheilophila Schneid. is a naturally occurring Salix species in Mu Us Sandy Land, Inner Mongolia, China. We focused on the morphological adaptability of S. cheilophila to sand dune burial. For morphological measurements, 32 S. cheilophila seedlings were removed from a community which was in the process of being buried by a shifting sand dune. Each seedling collected included the entire root system. We measured the number, length, and biomass of the adventitious roots, primary lateral roots, and taproot, and compared the morphological characteristics of the root system, including adventitious roots, for seedlings buried to various levels in the sand. The growth range of adventitious roots increased as the length of the buried portion of the main shoot increased. In addition, the total dry weight of all current-year shoots tended to increase gradually with increasing total dry weight of the adventitious roots. These results suggest that S. cheilophila tends to make use of the sedimentary sand layer that accompanies shifting sand dunes. However, there was no correlation between biomass or number of adventitious roots and the length of the buried part of the main shoot. Thus, S. cheilophila does not grow adventitious roots proportional to the buried part. These morphological characteristics of the root system, including the adventitious roots, may indicate that S. cheilophila has poor morphological adaptability to sand dune burial. 相似文献
22.
含par位点的重组质粒Psjm3的构建及其稳定性研究 总被引:3,自引:0,他引:3
利用自然质粒pSC101par位点的分离稳定性功能,构建了含par位点的质粒pSJM4和pSJM3,通过在同样宿主E.coli HB101中的稳定性比较研究表明,不含par位点的重组质粒pSJ3很不稳定,E.coli G3(pSJ3)在培养到第10代时已开始出现pSJ3的丢失,到培养至50代时则已全部丢失;而含par位点的重组质粒pSJM3则表现得十分稳定,E.coli G3-1(pSJM3)经70代培养,仍无明显的质粒丢失现象,其稳定率保持97%以上。通过对不含par和含par的非重组质粒pUC18和pSJM4的稳定性比较也获得同样的结果。通过对E.coliG3(pSJ3)和E.coli G3-1(pSJM3)的产酶活性比较研究表明,G3-1菌株明显高于G3菌株,说明我们构建的重组质粒pSJM3上的par位点功能不仅没有因外源基因的表达而受影响,而且有利于外源基因的表达。 相似文献
23.
X Q Mao P S Gao M H Roberts T Enomoto M Kawai S Sasaki S R Shaldon P Coull Y Dake C N Adra A Hagihara T Shirakawa J M Hopkin 《Biochemical and biophysical research communications》1999,262(1):259-262
Endothelin-1 (ET-1) is a 21 amino acid peptide released from several types of bronchial cells. It operates through two types of receptors, type A(ET-RA) and type B(ET-RB) and has various activities in the pathophysiology of atopic asthma. These genes are localised on different chromosomes where genome-wide searches have identified linkage for atopic asthma, thus supporting the candidacy of ET-1 and its receptors for atopic asthma. A genetic association study was performed with variants of these three genes in both British (n = 300) and Japanese populations (n = 200). No significant association was found between variants of EDN1 and EDNRB genes, and atopic asthma in either population. However, variants of EDNRA gene showed a marginal association with atopy [odds = 0.39(95% CI: 0.17-0.89), p = 0.022, Pc = 0.066], especially with antigen specific IgE levels [odds = 0.31 (95% CI: 0.20-0.77), p = 0.006, Pc = 0.018] in the British population. These findings suggest that EDNRA is a major candidate locus for atopy on chromosome 4. 相似文献
24.
Ying Wang Yunjing Zhang Xinwan Su Qiongzi Qiu Yuan Yuan Chunhua Weng Sailan Zou Yan Tian Weidong Han Pengyuan Liu Xingyi Guo Jianhua Mao Xianghui Fu Ping Wang Weiqiang Lin 《International journal of biological sciences》2022,18(4):1491
Clear cell renal cell carcinoma (ccRCC) is a primary kidney cancer with high aggressive phenotype and extremely poor prognosis. Accumulating evidence suggests that circular RNAs (circRNAs) play pivotal roles in the occurrence and development of various human cancers. However, the expression, clinical significance and regulatory role of circRNAs in ccRCC remain largely unclear. Here we report that circDVL1 to be reduced in the serums and tissues from ccRCC patients, and to negatively correlate with ccRCC malignant features. Overexpression of circDVL1 inhibits proliferation, induces G1/S arrest, triggers apoptosis, and reduces migration and invasion in different ccRCC cells in vitro. Correspondingly, circDVL1 overexpression suppresses ccRCC tumorigenicity in a mouse xenograft model. Mechanistically, circDVL1 serves as a sponge for oncogenic miR-412-3p, thereby preventing miR-412-3p-mediated repression of its target protocadherin 7 (PCDH7) in ccRCC cells. Collectively, our results demonstrate that circDVL1 exerts tumor-suppressive function during ccRCC progression through circDVL1/miR-412-3p/PCDH7 axis, and suggest that circDVL1 could be a novel diagnostic and prognositc marker and therapeutic target for ccRCC. 相似文献
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Mao AJ Bechberger J Lidington D Galipeau J Laird DW Naus CC 《The Journal of biological chemistry》2000,275(44):34407-34414
Given the roles proposed for gap junctional intercellular communication in neuronal differentiation and growth control, we examined the effects of connexin43 (Cx43) expression in a neuroblastoma cell line. A vesicular stomatitis virus G protein (VSVG)-pseudotyped retrovector was engineered to co-express the green fluorescent protein (GFP) and Cx43 in the communication-deficient neuro-2a (N2a) cell line. The 293 GPG packaging cell line was used to produce VSVG-pseudotyped retrovectors coding for GFP, Cx43, or chimeric Cx43.GFP fusion protein. The titer of viral supernatant, as measured by flow cytometry for GFP fluorescence, was approximately 2.0 x 10(7) colony form units (CFU)/ml and was free of replication-competent retroviruses. After a 7-day treatment with retinoic acid (20 microm), N2a transformants (N2a-Cx43 and N2a-Cx43.GFP) maintained the expression of Cx43 and Cx43.GFP. Expression of both constructs resulted in functional coupling, as evidenced by electrophysiological and dye-injection analysis. Suppression of cell growth correlated with expression of both Cx43 or Cx43.GFP and retinoic acid treatment. Based on morphology and immunocytochemistry for neurofilament, no difference was observed in the differentiation of N2a cells compared with cells expressing Cx43 constructs. In conclusion, constitutive expression of Cx43 in N2a cells does not alter retinoic acid-induced neuronal differentiation but does enhance growth inhibition. 相似文献
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29.
Pombo I Martin-Verdeaux S Iannascoli B Le Mao J Deriano L Rivera J Blank U 《The Journal of biological chemistry》2001,276(46):42893-42900
Following activation through high affinity IgE receptors (FcepsilonRI), mast cells release, within a few minutes, their granule content of inflammatory and allergic mediators. FcepsilonRI-induced degranulation is a SNARE (soluble N-ethylmaleimide attachment protein receptors)-dependent fusion process. It is regulated by Rab3D, a subfamily member of Rab GTPases. Evidence exists showing that Rab3 action is calcium-regulated although the molecular mechanisms remain unclear. To obtain an understanding of Rab3D function we have searched for Rab3D-associated effectors that respond to allergic triggering through FcepsilonRI. Using the RBL-2H3 mast cell line we detected a Ser/Thr kinase activity, termed here Rak3D (from Rab3D-associated kinase), because it was specifically co-immunoprecipitated with anti-Rab3D antibody. Rak3D activity, as measured by its auto- or transphosphorylation, was maximal in resting cells and decreased upon stimulation. The down-regulation of the observed activity was blocked with EGTA, but not with other degranulation inhibitors, suggesting that its activity functions downstream of calcium influx. We found that Rak3D phosphorylates the NH(2)-terminal regulatory domain of the t-SNARE syntaxin 4, but not syntaxin 2 or 3. The phosphorylation of syntaxin 4 decreased its binding to its partner SNAP23. Thus, we propose a novel phosphorylation-dependent mechanism by which Rab3D controls SNARE assembly in a calcium-dependent manner. 相似文献
30.
Zhihong Wan Yichen Wu Jing Yi Shaoli You Hongling Liu Zhiqiang Sun Bing Zhu Hong Zang Chen Li Fangfang Liu Dongze Li Yuanli Mao Shaojie Xin 《PloS one》2015,10(1)