一类个体寿命有限的纯生过程

讨论了一类个体的寿命有限且一生分为若干个阶段的纯生过程 （ｐｕｒｅ ｂｉｒｔｈ ｐｒｏ－ｃｅｓｓ），其中每个阶段的存活率，繁殖率，其繁殖符合 Ｐｏｉｓｓｏｎ过程．证明了其小群体的繁衍分布服从分布；ｉ和ｊ两个不同阶段繁殖的时间间隔之比的密度函数为Ｆｉｂｏｎａｃｃｉ过程［４］中总体的期望数和寿命与指数分布有关等性质．     

Heterologous expression of Vitis vinifera SNF1-related kinase 1.1 gene in Arabidopsis akin10 mutant reveals sthe signaling regulatory network of sucrose metabolism

Plant Growth Regulation - Grapevine (Vitis vinifera L.) is the widely cultivated important fruit crop. The regulation of sucrose metabolism is relevant for the quality improvement of grape berry....     

Linc-KILH potentiates Notch1 signaling through inhibiting KRT19 phosphorylation and promotes the malignancy of hepatocellular carcinoma

Long noncoding RNAs (LncRNAs) are emerging as crucial regulators in the pathophysiological process of various tumors, including HCC. Here, we identify a novel lncRNA Linc-KILH (KRT19 interacting long noncoding RNA in hepatocellular carcinoma), which is significantly up-regulated in HCC tissues and positively correlated with larger tumor size, severer microvascular invasion, more intrahepatic metastasis and decreased survival of HCC patients. Silence of Linc-KILH remarkably inhibited the proliferation and metastasis abilities of KRT19-positive HCC cells in vitro and in vivo. Mechanistically, Linc-KILH interacts with KRT19 and then inhibits the phosphorylation of KRT19 on Ser35, thereby, enhancing the translocation of KRT19 from cytoplasm to membrane in KRT19 positive HCC cells. Additionally, we validated that KRT19 interacts with β-catenin but not RAC1 in HCC cells. Linc-KILH enhanced the interaction between β-catenin and KRT19 in cytoplasm and promoted the nuclear translocation of β-catenin in HCC cells. Furthermore, Linc-KILH could enhance the promoting function of KRT19 on Notch1 signaling with the existence of KRT19 in HCC cells. Collectively, we revealed that Linc-KILH exerts a vital function in KRT19 positive HCC progression and may likely be developed into an effective therapeutic target for HCC.     

Piwil2 Inhibits Keratin 8 Degradation through Promoting p38-Induced Phosphorylation To Resist Fas-Mediated Apoptosis

The piwi-like 2 (piwil2) gene is widely expressed in tumors and protects cells from apoptosis induced by a variety of stress stimuli. However, the role of Piwil2 in Fas-mediated apoptosis remains unknown. Here, we present evidence that Piwil2 inhibits Fas-mediated apoptosis. By a bacterial two-hybrid screening, we identify a new Piwil2-interacting partner, keratin 8 (K8), a major intermediate filament protein protecting the cell from Fas-mediated apoptosis. Our results show that Piwil2 binds to K8 and p38 through its PIWI domain and forms a Piwil2/K8/P38 triple protein-protein complex. Thus, Piwil2 increases the phosphorylation level of K8 Ser-73 and then inhibits ubiquitin-mediated degradation of K8. As a result, the knockdown of Piwil2 increases the Fas protein level at the membrane. In addition to our previous finding that Piwil2 inhibits the expression of p53 through the Src/STAT3 pathway, here we demonstrate that Piwil2 represses p53 phosphorylation through p38. Our present study indicates that Piwil2 plays a role in Fas-mediated apoptosis for the first time and also can affect p53 phosphorylation in tumor cells, revealing a novel mechanism of Piwil2 in apoptosis, and supports that Piwil2 plays an active role in tumorigenesis.     

Fluorescence detection of hydrazine in an aqueous environment by a corrole derivative

Broadly, the industrial applications of hydrazine cause environmental pollution and damage to living organisms because of the high toxicity of hydrazine. Therefore, monitoring hydrazine in the environmental system is of great significance to human health. Here, a new fluorescent probe PC-N ₂ H ₄ based on corrole dye was developed for the detection of hydrazine that had excellent specificity, low limit of detection (LOD: 88 nM), and a wide pH range (6–12). Upon addition of hydrazine into the probe solution, the strong red fluorescence was ‘turned on’ centred at 653 nm with a 127-fold fluorescence intensity enhancement. The detection mechanism was proved using ESI-MS, ¹H NMR, and density functional theoretical calculations. Importantly, the probe was utilized to fabricate a ready-to-use test strip to realize the visual inspection of hydrazine. Furthermore, PC-N ₂ H ₄ was successfully applied for practical detection of hydrazine in water samples with satisfactory recoveries ranging from 96.2% to 105.0%, and indicating that the designed PC-N ₂ H ₄ is highly promising for hydrazine detection in an aqueous environment. Considering the diverse toxicological functions of hydrazine, PC-N ₂ H ₄ was also successfully used to image exogenous hydrazine in HeLa cells and zebrafish.