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江伟康  吴隽宇 《生态学报》2021,41(5):1747-1757
经济发展与人口集聚引起的土地利用变化对一个地区的生态环境影响显著,生境质量评价在一定程度上可以反映区域生物多样性的状况。分析地区生境质量与社会经济、人口密度的关系,能够为区域生态安全及可持续发展提供科学依据。运用InVEST模型,以粤港澳大湾区2005、2010、2015、2018年四期土地利用数据分析生境质量的时空演变特征,结合社会经济及人口分布数据探究各地区城市发展与生境质量的权衡关系,并预测2030年大湾区不同情景下生境质量状况。结果表明:(1)2005-2018年粤港澳大湾区整体生境质量逐年降低,呈现出中部低、四周高的环状分布,生境破碎、建设用地增加是生境质量下降的主要原因。(2)珠三角九市生境质量与地区总GDP呈弱负相关,与第一产业产值呈中等正相关,与第二产业产值呈中等负相关,与第三产业产值呈弱正相关。(3)粤港澳大湾区生境质量与人口密度存在较大的不平衡,最主要的空间为高生境质量-低人口密度、低生境质量-高人口密度两种类型。(4)通过空间管制分区,预测2030年大湾区规划保护情景下大湾区平均生境质量较2018上升0.04,达到0.599,生境质量有明显改善。  相似文献   
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As they age, adult stem cells become more prone to functional decline, which is responsible for aging‐associated tissue degeneration and diseases. One goal of aging research is to identify drugs that can repair age‐associated tissue degeneration. Multiple organ development‐related signaling pathways have recently been demonstrated to have functions in tissue homeostasis and aging process. Therefore, in this study, we tested several chemicals that are essential for organ development to assess their ability to delay intestinal stem cell (ISC) aging and promote gut function in adult Drosophila. We found that taurine, a free amino acid that supports neurological development and tissue metabolism in humans, represses ISC hyperproliferation and restrains the intestinal functional decline seen in aged animals. We found that taurine represses age‐associated ISC hyperproliferation through a mechanism that eliminated endoplasmic reticulum (ER) stress by upregulation of the target genes of unfolded protein response in the ER (UPRER) and inhibiting the c‐Jun N‐terminal kinase (JNK) signaling. Our findings show that taurine plays a critical role in delaying the aging process in stem cells and suggest that it may be used as a natural compound for the treatment of age‐associated, or damage‐induced intestinal dysfunction in humans.  相似文献   
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Gene synthesis is a convenient tool that is widely used to make genes for a variety of purposes. All current protocols essentially take inside-out approaches to assemble complete genes using DNA oligonucleotides or intermediate fragments. Here we present an efficient method that integrates gene synthesis and cloning into one step. Our method, which is evolved from QuikChange mutagenesis, can modify, extend, or even de novo synthesize relatively large genes. The genes are inserted directly into vectors without ligations or subcloning. We de novo synthesized a 600-bp gene through multiple steps of polymerase chain reaction (PCR) directly into a bacterial expression vector. This outside-in gene synthesis method is called Quikgene. Furthermore, we have defined an overlap region of a minimum of nine nucleotides in insertion primers that is sufficient enough to circularize PCR products for efficient transformation, allowing one to significantly reduce the lengths of primers. Taken together, our protocol greatly extends the current length limit for QuikChange insertion. More importantly, it combines gene synthesis and cloning into one step. It has potential applications for high-throughput structural genomics.  相似文献   
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Liu Q  Gao J  Chen X  Chen Y  Chen J  Wang S  Liu J  Liu X  Li J 《Molecular biotechnology》2008,40(3):231-240
A large number of tetratricopeptide repeat (TPR)-containing proteins have been shown to interact with the C-terminal domain of the 70 kDa heat-shock protein (Hsp70), especially those with three consecutive TPR motifs. The TPR motifs in these proteins are necessary and sufficient for mediating the interaction with Hsp70. Here, we investigate HBP21, a novel human protein of unknown function having three tandem TPR motifs predicted by computational sequence analysis. We confirmed the high expression of HBP21 in breast cancer and proliferative vitreoretinopathy (PVR) proliferative membrane and examined whether HBP21 could interact with Hsp70 using a yeast two-hybrid system and glutathione S-transferase pull-down assay. Previous studies have demonstrated the importance of Hsp70 C-terminal residues EEVD and PTIEEVD for interaction with TPR-containing proteins. Here, we tested an assortment of truncation and amino acid substitution mutants of Hsp70 to determine their ability to bind to HBP21 using a yeast two-hybrid system. The newly discovered interaction between HBP21 and Hsp70 along with observations from other studies leads to our hypothesis that HBP21 may be involved in the inhibition of progression and metastasis of tumor cells. Qinghuai Liu and Juanyu Gao have contributed equally to this work.  相似文献   
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陈康富  吴隽宇 《生态学报》2023,43(10):3855-3868
生态保护优先区识别对于城市群的整体性生态保护和区域生态安全具有重要意义。基于生态保护重要性评价识别城市群生态保护优先区,有助于保障生态系统服务的供给水平和维持生态系统的稳定性。以粤港澳大湾区(以下简称“大湾区”)为研究对象,首先通过增加粮食供给等生态系统服务指标和土地利用强度等生态脆弱性指标构建新的生态保护重要性评价指标体系,以弥补原指标体系忽略部分生态系统服务价值或者关乎生态脆弱性的重要因素所导致的评价结果片面性问题;然后运用结合空间主成分分析法和有序加权平均算子(Ordered Weighted Averaged, OWA)的主客观结合赋权法进行生态保护重要性评价的多情景模拟,并基于保护效率和权衡度进行多情景择优,由此所得最优情景的生态保护优先区的整体生态保护价值相对最高,且一定程度上减小了指标间权衡问题可能导致的评价误差;最终大湾区生态保护优先区面积为26406.04 km2,占大湾区陆域国土总面积的47.69%,主要分布在大湾区中部以外的肇庆、惠州、香港、广州北部、江门外环以及深圳东部沿海,同时优先区识别结果基本覆盖现有生态保护红线和周边大部分一般生态空间...  相似文献   
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多维度发展的文化线路理论对于整合地区文化遗产并提供整体性保护利用方法具有重要意义。有别于传统的文化遗产类型,文化线路通过整体性视角,将文化遗产资源在空间意义上的“点”延伸到“线”的层面,支持更大尺度范围内各区域遗产点之间的关联性,并在一个宏观且整体的线性空间尺度下认知与提升这些分散遗产点的重要性,从而达到整体保护的目的。以广东省江门市为例,基于文化线路定义、概念、构成条件及特征判读的研究,从时空变化性、历史功能性、文化交流性、多元整体性4个特征对江门文化遗产点进行分析与判读,梳理出江门文化遗产的历史文化脉络及其空间分布现状。从而为确立与展现具有“微观尺度遗产串联—宏观尺度文化认同”特征的江门华侨华人文化线路提供依据。  相似文献   
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