DNA chip-based expression profile analysis indicates involvement of the phosphatidylinositol signaling pathway in multiple plant responses to hormone and abiotic treatments

The phosphatidylinositol (PI) metabolic pathway is considered critical in plant responses to many environmental factors, and previous studies have indicated the involvement of multiple PI-related gene families during cellular responses.Through a detailed analysis of the Arabidopsis thaliana genome, 82 polypeptides were identified as being involved in PI signaling. These could be grouped into different families including PI synthases (PIS), PI-phosphate kinases (PIPK),phospholipases (PL), inositol polyphosphate phosphatases (IPPase), inositol polyphosphate kinases (IPK), PI transfer proteins and putative inositol polyphosphate receptors. The presence of more than 10 isoforms of PIPK, PLC, PLD and IPPase suggested that these genes might be differentially expressed during plant cellular responses or growth and development. Accordingly, DNA chip technology was employed to study the expression patterns of various isoforms.In total, 79 mRNA clones were amplified and used for DNA chip generation. Expression profile analysis was performed using samples that represented multiple tissues or cellular responses. Tested samples included normal leaf, stem and flower tissues, and leaves from plants treated with various hormones (auxin, cytokinin, gibberellin, abscisic acid and brassinosteroid) or environmental factors (temperature, calcium, sodium, drought, salicylic acid and jasmonic acid).Results showed that many PI pathway-related genes were differentially expressed under these experimental conditions.In particular, the different isoforms of each family were specifically expressed in many cases, suggesting their involvement in tissue specificity and cellular responses to environmental conditions. This work provides a starting point for functional studies of the relevant PI-related proteins and may help shed light onto the role of PI pathways in development and cellular responses.     

不完全酶切去除载体多个相同酶切位点的简易方法

以去除真核表达载体pIGF3的3个EcoR Ⅰ位点为例,介绍一种通过不完全酶切去除载体多个相同酶切位点的方法。本方法步骤简单,经济实用。     

肺内调节肽对兔支气管上皮细胞与嗜酸性粒细胞粘附功能的影响及机制探讨

为了探讨肺内调节肽在各类过敏性炎症发生,发展中的作用,我们观察了血管活性肠肽（vasoactive intestinal peptide,VIP)、表皮生长因子（epidermal growth factor,EGF)、内皮素-1（endothelin-1,ET-1)、降钙素基因相关肽（calcitonin gene-related peptide,CGRP)在未受应激与臭氧应激两种条件下对支气管上皮细胞（bronchial epithelial cell,BEC)与嗜酸性粒细胞（eosinophil,EOS)粘附的影响,结果发现,VIP、EGF可使O3应激的BEC与EOS的粘附率下降,下调气道上皮炎症反应：ET-1、CGRP可使未受应激的BEC与EOS的粘附率增加,诱发炎症损伤反应;CGRP还能加重臭氧的应激反应;ET-1、CGRP的效应可被W7、H7阻断,抗细胞间粘附分子-1（intercel-lular adhesion molecule,ICAM-1)抗体能阻断BEC与EOS的粘附,提示介导BEC与EOS粘附的粘附分子可能是ICAM-1。     

新型导向分子与海马内联系的发育

发育轴突向正确的靶位生长是建立精确神经环路的基础。海马内主要的传入通路是内嗅皮层－海马通路,兴奋性合缝,联合系统中隔投射,它们以层状形式终止于齿回与Ammon角的靶神经元。在海马内部,齿回与CA3区的苔藓纤维,CA3区与CA1之间均建立了特异的纤维联接系统。细胞培养测定和包括基因敲除在内的分子生物学策略研究表明,在发育过程中复杂的导向信号网络对海马内联系的形成有重要调节作用。分泌性Ⅲ型semaphorins,netrin 1和Slit蛋白及局部膜或基底锚分子如ephrin A亚家族配体,共同介导了海马内联系的发育。     

化学刺激或电刺激大鼠穹窿下器官诱发的饮水行为和脑内c-fos表达

目的对化学刺激和电刺激穹窿下器官(subfornical organ, SFO)诱发的饮水量和脑内c-fos表达的结果是否不同进行比较. 方法向大鼠SFO内微量注射L-谷氨酸作为化学刺激,用恒流刺激SFO作为电刺激,记录诱发的1 h内饮水量,用免疫组化方法检测脑内Fos蛋白表达.结果电刺激和化学刺激SFO均能诱导相似的饮水行为,其诱饮率分别为75%和85.7%,1 h平均饮水量分别为(0.28±0.22) ml 和(0.31±0.15) ml ,明显高于各自的对照组(P<0.05),并均能使前脑的 11个脑区(终板血管器官, 正中视前核,室旁核,视上核,下丘脑外侧区,丘脑室旁核,联合核和中央内侧核,终纹床核,穹窿周背区和无名质)和后脑的4个脑区(最后区,孤束核,臂旁外侧核和中缝背核)相似的Fos蛋白表达.结论刺激SFO所诱导的饮水行为和脑内Fos蛋白表达是激活其神经元胞体的结果.     

Nuclear apoptosis induced by isolated mitochondria

We isolated and purified mitochondria from mouse livers and spinach leaves.When added into egg extracts of Xenopus laevis,they caused nuclei of mouse liver to undergo apoptotic changes.Chromatin condensation,margination and DNA ladder were observed.After incubating isolated mitochondria in some hypotonic solutions,and centrifuging these mixtures at mgh speed,we got mitochondrial supernatants.It was found that in the absence of cytosolic factor,the supernatant alone was able to induce apoptotic changes in nuclei.The effective components were partly of protein.DNA fragmentation was partly inhibited by caspase inhibitors AC-DEVD-CHO and AC-YVAD-CHO.Meanwhile,caspase inhibitors fully blocked chromatin condensation.Primary characterization of the nuclear endonuclease(s) induced by mitochondrial supernatants was also conducted.It was found that this endonuclease is different from endonuclease G,cytochrome c-induced nuclease,or Ca^2 -activated endonuclease.     

苏皖象山群下部一些本内苏铁目铁化石的表皮构造研究

报道象山群下部的本内苏铁植物５属６种：Ｔｙｒｍｉａ ｓｕｓｏｎｇｅｎｓｉｓ ｓｐ ｎｏｖ．Ｐｔｅｒｏｐｈｙｌｌｕｍ ｓｐ．１,Ｐ．ＳＰ．２,Ａｎｏｍｏｚａｍｉｔｅｓ ｑｕａｄｒａｔｕｓ ｓｐ．ｎｏｖ．,Ｏｔｏｚａｍｉｔｅｓ ｈｓｉａｎｇｃｈｉｅｎｓｉｓ Ｓｚｅ,Ｎｉｌｓｏｎｉｏｐｔｅｒｉｓ ｖｉｔｔａｔａ Ｆｌｏｒｉｎ,对其表皮构造进行了详细的描述。     

低氧、血管紧张素Ⅱ对肺内小动脉平滑肌细胞膜Ca2 ┐ATPase活力的影响

本课题观察了低氧及血管紧张素Ⅱ（ａｎｇｉｏｔｅｎｓｉｎⅡ,ＡｎｇⅡ）对分离培养家兔肺内小动脉平滑肌细胞（ＰＡＳＭ－Ｃｓ）膜Ｃａ２＋－ＡＴＰａｓｅ活力的影响,同时用钙通道阻断剂维拉帕米（ｖｅｒａｐａｍｉｌ,ＶＰ）进行干预,进一步了解细胞内钙与Ｃａ２＋－ＡＴＰａｓｅ活力的关系。结果表明：ＰＡＳＭＣｓ膜Ｃａ２＋－ＡＴＰａｓｅ活力对低氧具有短暂的耐受性,随低氧时间延长,Ｃａ２＋－ＡＴＰａｓｅ活力呈时间依赖性抑制;低氧、ＡＮＧⅡ均能抑制Ｃａ２＋－ＡＴＰａｓｅ活力（Ｐ＜０．０１）低氧＋ＡⅡ对Ｃａ２＋－ＡＴＰａｓｅ活力的抑制具叠加效应（Ｐ＜０．０５）;ＶＰ可逆转低氧、ＡｎｇⅡ、低氧＋ＡｎｇⅡ对Ｃａ２＋－ＡＴＰａｓｅ活力的抑制（Ｐ＜０．０１）。结果提示：低氧,ＡＮＧⅡ可通过抑制肺血管平滑肌细胞膜Ｃａ２＋－ＡＴＰａｓｅ活力而可能削弱肺血管平滑肌舒张功能也可能是低氧性肺动脉高压（ＨＰＨ）形成的原因之一。     

动脉内灌药,内支架安置双介入治疗十二指肠恶性梗阻

通过动脉内灌药,内支架安置双介入治疗提高对十二指肠恶性梗阻姑息性治疗的疗效。十二指肠恶性梗阻病例１４例,男５例,女９例,年龄２０－６９岁,经口安置自膨式十二指肠金属支架共１５枚,其中１２例在支架安置后定期行肿瘤供血动脉插管介入化疗,所有病例梗阻症状解除,２例未行动脉灌药治疗者分别于２个月及４个月死亡,１２例双介入者生存期明显延长,最短６月,最长已达一年,结论：双介入治疗能够姑息治疗疗效延长晚期瘤患     

核糖体失活蛋白与超螺旋DNA相互作用的原子力显微镜直接观察

运用原子力显微镜研究了核糖体失活蛋白 (RIP)与超螺旋DNA相互作用 ,发现这类毒蛋白 (克木毒蛋白和蓖麻毒蛋白A链 ) ,既能与超螺旋形式的DNA结合 ,又能结合在超螺旋DNA分子中未解旋的双链环区 .在与超螺旋DNA结合后 ,引起超螺旋DNA构象变化以利解旋并与双链DNA结合 ,进而将松弛的DNA双链切成缺口或线性形式 .这说明RIP是一种超螺旋DNA结合蛋白 ,并表现出依赖超螺旋的DNA内切酶活性