PHB3 Maintains Root Stem Cell Niche Identity through ROS-Responsive AP2/ERF Transcription Factors in Arabidopsis

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EFEMP2 Mediates GALNT14-Dependent Breast Cancer Cell Invasion

N-Acetylgalactosaminyltransferase-14 (GALNT14) is a member of acetylgalactosaminyltransferases family. We have shown that GALNT14 could promote breast cancer cell invasion. However, the underlying molecular mechanism is unclear. Here, using yeast two hybrid, we find that EGF-containing fibulin-like extracellular matrix protein 2 (EFEMP2) interacts with GALNT14. Both in vitro and in vivo binding assays show that EFEMP2 is associated with GALNT14. Moreover, we find that GALNT14 mediates glycosylation of EFEMP2. EFEMP2 significantly increased the invasion ability of breast cancer cells including MCF-7 and MBA-MD-231 cells, and this phenomenon is suppressed by knockdown expression of GALNT14. In addition, the GALNT14-dependent O-glycosylation of EFEMP-2 regulates the stability of EFEMP-2 protein in breast cancer cells. Taken together, our results demonstrate a novel molecular mechanism underlying breast cancer invasion.     

SRSF5 functions as a novel oncogenic splicing factor and is upregulated by oncogene SRSF3 in oral squamous cell carcinoma

Alternative splicing of precursor messenger RNA has been increasingly associated with tumorigenesis. The serine/arginine-rich protein (SR) family plays key roles in the regulation of pre-mRNA alternative splicing. Increasing evidence has demonstrated that the SR protein family is involved in tumorigenesis. However, the functions and mechanisms of SR proteins in tumourigenesis remain largely unknown. In the present study, we discovered that serine/arginine-rich splicing factor 5 (SRSF5) is a novel oncogenic splicing factor that is overexpressed in oral squamous cell carcinoma (OSCC) tissues and cells, being crucial for OSCC cell proliferation and tumor formation. Overexpression of SRSF5 transformed immortal rodent fibroblasts to form tumors in nude mice, while downregulation of SRSF5 in oral squamous cell lines retarded cell growth, cell cycle progression, and tumor growth. The expression of SRSF5 is controlled by an autoregulation mechanism. Serine/arginine-rich splicing factor 3 (SRSF3) has been identified as an oncogene. We found that SRSF5 is a novel target of SRSF3. SRSF3 impairs the autoregulation of SRSF5 and promotes SRSF5 overexpression in cancer cells. Altogether, the present study demonstrated that SRSF5 is a novel oncogene that is upregulated by SRSF3 in OSCC cells.     

Abscisic acid negatively modulates plant defence against rice black‐streaked dwarf virus infection by suppressing the jasmonate pathway and regulating reactive oxygen species levels in rice

Abscisic acid (ABA) plays a multifaceted role in plant immunity and can either increase resistance or increase susceptibility to some bacterial and fungal pathogens depending on the pathosystem. ABA is also known to mediate plant defence to some viruses. In this study, the relationship between the ABA pathway and rice black‐streaked dwarf virus (RBSDV) was investigated in rice. The expression of ABA pathway genes was significantly reduced upon RBSDV infection. Application of exogenous hormones and various ABA pathway mutants revealed that the ABA pathway plays a negative role in rice defence against RBSDV. Exogenous hormone treatment and virus inoculation showed that ABA inhibits the jasmonate‐mediated resistance to RBSDV. ABA treatment also suppressed accumulation of reactive oxygen species by inducing the expression of superoxidase dismutases and catalases. Thus, ABA modulates the rice–RBSDV interaction by suppressing the jasmonate pathway and regulating reactive oxygen species levels. This is the first example of ABA increasing susceptibility to a plant virus.     

Radix Scutellariae Attenuates CUMS-Induced Depressive-Like Behavior by Promoting Neurogenesis via cAMP/PKA Pathway

Chronic mild unpredictable stress (CUMS) causes neurogenesis damage in the hippocampus and depressive-like behaviors such as cognitive impairment. Radix Scutellariae from the dry root of Scutellaria baicalensis Georgi, with the common name Baikal skullcap. In this study, we demonstrated that Radix Scutellariae (RS 500, 1000 mg/kg) notably improved the behavior of the rat, such as shortened escape latency in morris maze test, reduced immobility time in tail suspension test and in forced swimming test, as well as increased sucrose consumption in sucrose preference test. In addition, RS alleviated the damage CUMS-induced neurogenesis and the reduced levels of BrdU; DCX and NeuN, the neurons hallmark of hippocampus neurogenesis. Moreover, associated proteins in cAMP/PKA pathway were up-regulated after RS treatment. By HPLC analysis, we found that RS decoction contains four main components, including baicalin, baicalein, wogonoside and wogonin, respectively. In conclusion, RS could exert a natural antidepressant with improving depressive-like behavior via regulation of cAMP/PKA neurogenesis pathway.     

刺激游离的弓状核不再抑制丘脑束旁核神经元的伤害性反应

以Ｈａｌａｓｚ刀游离大鼠下丘脑弓状核区,切断ＡＲＣ与其它脑区的神经而保持其与垂体的神经内分泌联系。用细胞外记录单位放电的方法观察了刺激这种游离的ＡＲＣ对丘脑束旁核神经元伤害性反应的影响。     

小鼠γ干扰素/上皮生长因子受体结合域融合蛋白的构建及其抗肿瘤活性的提高

采用基因工程和蛋白质工程技术,构建了一种新颖的小鼠γ干扰素/上皮生长因子受体结合域融合蛋白,该蛋白保留了完全的抗病毒活性,达到10~8IU/L菌液;利用~(125)I-mEGF进行的受体结合竞争抑制实验,证明融合蛋白所带有的上皮生长因子结合域有与EGF竞争结合受体的功能;体外抗乳腺癌细胞增殖实验证明融合蛋白具有比干扰素母体分子更明显的抗肿瘤细胞增殖效应;在小鼠B16黑色素瘤模型上,融合蛋白和干扰素母体治疗后的2组小鼠,平均瘤体重量分别为1.6和2.6g,具有统计学差异.表明融合蛋白具有比干扰素母体分子更强的体内肿瘤生长抑制作用.     

极低密度脂蛋白对巨噬细胞载脂蛋白E基因表达的调节

巨噬细胞（M）是动脉粥样硬化（AS）斑块中泡沫细胞的主要来源之一,它可通过其表面的多种脂蛋白受体介导摄取合APOB或APOE的脂蛋白,导致M的脂质增加．此外,M有较强的分泌ApOE的能力[1],这一现象虽已发现多年,但意义尚不清楚VLDL是一种含APOE的脂蛋白,它能通过M膜上识别APOE的受体进入M,从而促进Mg内脂质堆积,并与AS密切相关[2,3]．流行病学调查发现在我国的高脂血症中2／3为VLDL升高为主的高甘油三酯（HTG）血症．另外,Evans等报道HTG血症患者的血浆中以ApoE－poorVLDL升高为主,它们在血浆中清除的速率较Apo…     

半导体激光辐照对花生种子活力的影响

采用３５０ｎｗ,８１０ｎｍ近红外光导体激光辐照花生干种子,经激光辐照后,种子胚根生长速度加快,胚根长度增加,侧根数目增加,种子出苗率提高。幼苗苗鲜重与根鲜重指标均高于对照组。实验证明,适当剂量的近红外半导体激光辐照可提高花生种子活力,促进幼苗生长。