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61.
62.
Physiological response of riparian plants to watering in hyper-arid areas of Tarim River, China 总被引:1,自引:0,他引:1
The physiological responses and adaptive strategies of Populus euphratica Oliv. (arbor species), Tamarix ramosissima Ldb. (bush species), and Apocynum venetum L. (herb species) to variations in water and salinity stress were studied in the hyper-arid environment of the Tarim River
in China. The groundwater table, the saline content of the groundwater, as well as the content of free proline, soluble sugars,
plant endogenous hormones (abscisic acid (ABA), and cytokinins (CTK)) of the leaves of the three species were monitored and
analyzed at the lower reaches of the Tarim River in the study area where five transects were fixed at 100 m intervals along
a vertical sampling line before and after water release. Saline stress dramatically increased soluble sugar concentration
of the three species. Differences in sugar accumulation were determined among the species at different transects. The free
proline concentration of the leaves of T. ramosissima and P. euphratica showed a proportional decrease with various degrees of elevation of the groundwater table after water release. There was
a least correlation between the soluble sugars and proline stimulation in T. ramosissima. It was strongly suggested that T. ramosissima developed a different strategy to accumulate organic solutes to adapt to the stress environment. The soluble sugars and proline
accumulation responded to the changes of groundwater table independently: the former occurred under salt stress, whereas the
latter was more significant under drought stress. The concentration and the increase in concentration of ABA and CTK involved
in stress resistance of the three species were also determined. This increase in the hormone concentration in P. euphratica was different from that of the other two species. Expressed as a function of increase of ABA concentration in leaves, A. venetum and T. ramosissima showed a different solute accumulation in response to groundwater table. There was a significant correlation between ABA
accumulation and Δ [proline] in A. venetum as well as between ABA accumulation and Δ [sugar] in T. ramosissima.
Translated from Acta Ecologica Sinica, 2005, 25(8): 1966–1973 [译自: 生态学报] 相似文献
63.
In this work, a fundamental regulatory role of formate on thuringiensin production by resting cell of Bacillus thuringiensis YBT-032 was investigated. Nicotinamide adenine dinucleotide (NADH) production and formate dehydrogenase activity increased
with formate addition from 0.5 to 2.0 g/L, respectively. However, with the formate addition of 1.5 g/L, the activities of
pyruvate kinase and glucose 6-phosphate dehydrogenase reached a peak and increased by 316 and 150% relative to those of the
control, respectively. In addition, intracellular production of pyruvate, aspartate, citrate and adenine were significantly
enhanced by 75, 66, 32 and 78% as well. An improvement (90%) of thuringiensin production was also successfully obtained. Interestingly
to point out, thuringiensin yield was closely correlative with adenine production, and the linear relationship was also observed.
The results suggest that appropriate formate addition did act as a modulator and facilitate carbon flux in glycolysis and
pentose phosphate pathway to synthesize adenine and thuringiensin via intracellular NADH availability. 相似文献
64.
65.
Type 2C protein phosphatase (PP2C) is a monomeric enzyme and requires Mg(2+) or Mn(2+) for its activity. Up to now, seven PP2C-like genes have been identified in the genome of Saccharomyces cerevisiae. However, the protein encoded by the sixth PP2C-like gene, YCR079w, has not been demonstrated to have PP2C activity. In this study, we show that YCR079w confers a rapamycin-resistant function in yeast cells, and we also demonstrate that the YCR079w-encoded protein exhibits characteristics of a typical PP2C. Therefore, YCR079w encodes the sixth PP2C, PTC6, in budding yeast. 相似文献
66.
Wenkang Luan Xuanfeng Zhang Hongru Ruan Jinlong Wang Xuefeng Bu 《Journal of cellular physiology》2019,234(9):16609-16618
The long noncoding RNA (lncRNA) OIP5-AS1 has been considered to promote the growth and metastasis of many human tumors. However, the role of OIP5-AS1 in melanoma has not been reported. In this study, we found that OIP5-AS1 levels were significantly elevated in melanoma tissue and that high OIP5-AS1 expression was an independent risk factor for the poor survival of patients with melanoma. miR-217 suppressed glutamine catabolism in melanoma cells by targeting glutaminase (GLS), the rate-limiting enzyme of glutamine catabolism. We also demonstrated that OIP5-AS1 acted as a sponge of miR-217 to upregulate GLS expression, thus promoting glutamine catabolism and melanoma growth. Overall, this result elucidates a new mechanism for OIP5-AS1 in metabolism in melanoma and provides a potential therapeutic target for patients with melanoma. 相似文献
67.
Xinpan Chen Yiru Wu Zongli Diao Xue Han Dishan Li Xiongzhong Ruan Wenhu Liu 《Journal of cellular physiology》2019,234(12):22352-22364
C1q/tumor necrosis factor-related protein-3 (CTRP3) has been extensively reported as an important role involved in antifibrosis, antiapoptosis, and anti-inflammation. However, the role of CTRP3 involved in renal fibrosis remains unclear. Our current study explored the role of CTRP3 in renal fibrosis and its underlying mechanisms by using serums and renal biopsy specimens from renal fibrosis patients and control subjects, rats models with the surgery of unilateral ureteral obstruction (UUO) and human renal proximal tubular epithelial cells (HRPTEpiCs). We found that circulating levels of CTRP3 had no significant difference between renal fibrosis patients and healthy subjects; however, renal CTRP3 expression was markedly downregulated in the fibrotic region with an abundant expression of collagen-I. In UUO rat models, circulating levels of CTRP3 have not changed with the prolonged obstruction of the kidney; renal CTRP3 expression was decreased with the severity of renal fibrosis; adenovirus-mediated CTRP3 treatment inhibited renal interstitial fibrosis. In vitro experiments revealed that CTRP3 attenuates TGF-β1 induced tubular epithelial cells fibrotic changes; CTRP3 knockdown facilitates the expression of fibrotic markers in TGF-β1-induced HRPTEpiCs; recombinant CTRP3 or adenovirus-mediated CTRP3 overexpression significantly inhibited the Notch signaling pathway-associated factors, and knockdown of CTRP3 increased TGF-β1-mediated activation of the Notch signaling pathways. Collectively, our current study found that CTRP3 could improve renal fibrosis, to some extent, through inhibiting the Notch pathway. 相似文献
68.
[目的]探究慢生型花生根瘤菌III型分泌系统在花生-根瘤菌互作的功能。[方法]本研究采用同源重组和三亲本接合转移的方法,构建Bradyrhizobium sp.MZ5的III型分泌系统调节基因ttsI突变体;荧光定量PCR检测添加大豆苷元(Daidzein)和染料木黄酮(Genistein)诱导物后野生型和突变株转录水平上ttsI的表达量变化及其差异;蛭石结瘤实验分析ttsI基因突变对花生结瘤能力的影响。[结果]在转录水平上,大豆苷元和染料木黄酮对MZ5的III型分泌系统调节基因ttsI的表达具有显著的抑制作用(P<0.05)。在MZ5△ttsI突变体中ttsI基因的表达量都明显下调,与野生型菌株的相比都达到极显著水平(P<0.001)。蛭石结瘤实验表明,与野生型菌株相比,MZ5△ttsI突变体在不同花生品种的结瘤数和地上部干重都显著性降低。根瘤石蜡切片表明,MZ5△ttsI突变体在根瘤内的含菌量少于野生型菌株。[结论]Bradyrhizobium sp.MZ5菌株中的III型分泌系统在花生-根瘤菌互作中对结瘤有积极的促进作用。 相似文献
69.
Ronghua Yang Jingru Wang Ziheng Zhou Shaohai Qi Shubin Ruan Zepeng Lin Qi Xin Yan Lin Xiaodong Chen Julin Xie 《Developmental biology》2019,445(2):271-279
Local transplantation of stem cells has therapeutic effects on skin damage but cannot provide satisfactory wound healing. Studies on the mechanisms underlying the therapeutic effects of stem cells on skin wound healing will be needed. Hence, in the present study, we explored the role of Caveolin-1 in epidermal stem cells (EpiSCs) in the modulation of wound healing. We first isolated EpiSCs from mouse skin tissues and established stable EpiSCs with overexpression of Caveolin-1 using a lentiviral construct. We then evaluated the epidermal growth factor (EGF)-induced cell proliferation ability using cell counting Kit-8 (CCK-8) assay and assessed EpiSC pluripotency by examining Nanog mRNA levels in EpiSCs. Furthermore, we treated mice with skin burn injury using EpiSCs with overexpression of Caveolin-1. Histological examinations were conducted to evaluate re-epithelialization, wound scores, cell proliferation and capillary density in wounds. We found that overexpression of Caveolin-1 in EpiSCs promoted EGF-induced cell proliferation ability and increased wound closure in a mouse model of skin burn injury. Histological evaluation demonstrated that overexpression of Caveolin-1 in EpiSCs promoted re-epithelialization in wounds, enhanced cellularity, and increased vasculature, as well as increased wound scores. Taken together, our results suggested that Caveolin-1 expression in the EpiSCs play a critical role in the regulation of EpiSC proliferation ability and alteration of EpiSC proliferation ability may be an effective approach in promoting EpiSC-based therapy in skin wound healing. 相似文献
70.
Ruan Hong Xiao Renshun Jiang Xinghai Zhao Biao Wu Kai Shao Zongzuan Zhang Zhongjie Duan Huyang Song Yulin 《Molecular and cellular biochemistry》2019,450(1-2):199-207
Molecular and Cellular Biochemistry - Bone marrow mesenchymal stem cells (BMSCs) are multipotential differentiation cells which can differentiate into different cell types such as osteoblasts,... 相似文献