Effects of synthetic kainic acid on microfilament expression and gap junction in astrocytes

AIM：To study the effects of synthetic kainic acid (SKA) and 1-heptanol (1-Hep), a gap junction blocker, on the cytoskeletal filament expression in the astrocytes. METHODS：The neonatal rat brain was obtained from the Wistar rats (1 day old) and primary purified astrocytes were obtained by differential attachment for removing filamentoblasts and orbital shaker for removing the oligodendrocytes. The effects of SKA and other interventions on the morphologic changes and expression levels of skeleton protein filamentous actin (F-actin) were observed in the astrocytes after 24 h of the exposures by laser scanning confocal microscopy. The effect of 1-Hep on the expression of F-actin was also explored. RESULTS：Compared with control group, the fluorescence intensities in KCl group and KCl+SKA group were increased, and highly increased in KCl+SKA group. The F-actin filaments in the above 2 groups were more intensive, thickened and concentrated than those in control group, and more obvious in KCl+SKA group. l-Hep significantly decreased the expression of F-actin in KCl group and KCl+SKA group as compared with control group, and parts of the filamentous fracture were seen in the astrocytes in all 1-Hep-treated groups, in which some of the filamentous lines were crosscut. CONCLUSION：Increase in the expression of F-actin in the astrocytes affects the structure and function of the intercellular gap junctions, which may be involved in the mechanism of SKA-induced epilepsy.     

水葫芦肌动蛋白基因片段的克隆及序列分析

利用植物肌动蛋白保守片段设计简并引物,通过RT-PCR 扩增出水葫芦肌动蛋白基因片段并连接到 pMD19-T 载体,转化E. coli,测序。序列分析结果表明,该序列与油棕、小“果蕉等植物的相似性程度达到85%以上, 分子进化分析水葫芦肌动蛋白基因序列与油棕、小“果蕉等单子叶植物亲缘关系较近,但并没有与某些植物的肌动 蛋白很好地聚成一类。本研究所克隆得到的水葫芦肌动蛋白基因序列能够为进一步研究水葫芦其他基因的表达提 供内标。     

松材线虫actin基因全长cDNA的克隆

借助电子克隆和RACE方法,克隆了松材线虫生长发育关键基因actin的全长cDNA序列(登陆号:EU100952)。该序列共1 296个碱基,有一个完整ORF,起始密码子在48位,终止密码子在1 176位,编码376个氨基酸。     

Laryngeal rhabdomyoma in a dog

A 3‐year‐old, female spayed Australian Shepherd dog was presented to Veterinary Healthcare Associates in Winter Haven, FL with a history of respiratory stridor, difficulty swallowing, and a change in bark for approximately 3 months. Radiographs revealed a soft tissue mass caudal to the epiglottis. Oral and computerized tomographic (CT) examinations were performed under general anesthesia and revealed a small firm mass in the caudal larynx on the right side. Cytologic evaluation of a fine‐needle aspirate of the mass revealed cells consistent with a rhabdomyoma, oncocytoma, or granular cell tumor. Histopathologic interpretation was rhabdomyoma or oncocytoma. Histochemical staining with periodic acid‐Schiff was mostly negative with a low number of weakly positive cells and with phosphotungstic acid‐hematoxylin was strongly positive with visible cross striations. Tumor cells did not express pancytokeratin AE1/AE3, were strongly immunoreactive for myoglobin and muscle‐specific actin, and did not express vimentin except for a low number of weakly immunoreactive cells. These findings confirmed a diagnosis of rhabdomyoma. Primary neoplasia of the larynx is rare, and widely varying types of neoplasms have been documented in this location. Due to the cytologic and histologic similarities between rhabdomyoma, oncocytoma, and granular cell tumor, these neoplasms should be differentiated using histochemical staining and immunohistochemical analysis.     

蛋白质磷酸化对肌动球蛋白解离及其乙酰化水平的影响

[目的]研究肌球蛋白重链和肌动蛋白磷酸化对其乙酰化水平、肌动球蛋白解离及ATP酶活性的影响,为通过调控磷酸化水平改善肉品嫩度提供理论依据.[方法]以羊背最长肌为材料制备肌肉匀浆液,采用碱性磷酸酶抑制剂(抑制去磷酸化)和蛋白激酶抑制剂(抑制磷酸化)调控其磷酸化水平,在4℃分别孵育0、0.5、4、12、24、48和72 h...     

巴西橡胶树ADF6基因的克隆与表达分析

肌动蛋白解聚因子(Actin Depolymerizing Factor,ADF)是一种重要的肌动蛋白结合蛋白。ADF通过参与调控肌动蛋白的装配和解聚在多种生理过程中发挥重要作用。本研究通过RT-PCR技术从橡胶树胶乳中获得HbADF6基因的cDNA和基因组序列,序列分析显示HbADF6基因的开放阅读框为441 bp,共编码146个氨基酸,基因组序列由2个内含子和3个外显子组成。实时荧光定量PCR结果表明,HbADF6基因在所有检测组织中均表达,其中树皮中表达量最高,叶片中表达量最低。HbADF6基因的表达受乙烯利(ET)和碘化钾(KI)调控,并与排胶时间和死皮有关。此结果表明HbADF6基因可能在橡胶树乙烯响应、死皮和排胶过程中发挥重要作用。      

13种植物actin基因的密码子使用特性分析

[目的]分析13种植物actin基因的密码子组成、密码子偏性及聚类关系,了解其密码子使用模式及影响密码子使用的因素,为深入研究分子进化及物种进化提供参考.[方法]运用CodonW 1.4.4软件分析13种植物的肌动蛋白基因(actin)密码子组成及使用参数,并对影响密码子偏性的因素进行研究.应用MEGA 4.1对13条基因的CDS序列进行聚类分析,采用SPSS 20.0进行密码子偏性的聚类分析.[结果]双子叶植物中actin基因的GC含量为45.0%~51.2%、GC3s含量为36.3%~53.8%,单子叶植物中GC含量为53.0%~58.3%、GC3s含量为60.9%~75.8%;actin基因在单子叶植物中偏爱G/C结尾的密码子,双子叶植物中偏爱A/T结尾的密码子.GC和GC3s与有效密码子数(ENC)呈极显著负相关(P<0.01),相关系数均为-0.906.ENC绘图分析结果表明,actin基因密码子偏性同时受突变和选择压力影响,单子叶植物受选择压力影响的程度大于双子叶植物.基于actin基因密码子偏性的聚类将单子叶植物高粱、玉米聚为一类,水稻、大麦、竹聚为一类,8种双子叶植物聚为一类.[结论]actin基因密码子偏性与碱基组成密切相关,其密码子偏性在单、双子叶植物间存在差异,依据密码子偏性的聚类能在一定程度上反映物种间的亲缘关系.     

小麦生理型雄性不育系微丝骨架和胼胝质的变化与其相关基因的表达分析

【目的】研究生理型雄性不育小麦花粉细胞内微丝和胼胝质的结构及其相关基因的表达,并揭示其与生理型雄性不育的关系,为进一步研究化学杂交剂SQ-1诱导小麦生理型雄性不育的机理提供一定的理论依据。【方法】以化学杂交剂SQ-1诱导的生理型雄性不育系ms(A)-西农1376及对应正常可育系(A)-西农1376为试材,用TRITC-phalloidin标记细胞内微丝,苯胺蓝标记胼胝质,qRT-PCR技术分别对肌动蛋白解聚因子TaADF（Actin depolymerizing factor）、类葡聚糖合成酶TaGSL（Glucan synthase-like）进行差异表达分析。【结果】(1)在减数分裂前期Ⅰ、中期Ⅰ、后期Ⅰ这三个时期,生理型雄性不育系花粉细胞的微丝结构与可育系没有显著差异：前期Ⅰ,微丝分布于整个细胞质中,细胞核区域也可见少量微丝环绕细胞核;中期Ⅰ,微丝分布在细胞质中,在形成纺锤体部位染色更深,形成纺锤体微丝,由细胞两极发出的纺锤体微丝伸向赤道板;后期Ⅰ,在向两极移动的染色体的中间部位染色较深,微丝分布较多。(2)在早末期Ⅰ,与可育系相比,不育系花粉细胞没有形成清晰且明显可见的中国灯笼状成膜体微丝结构,且在细胞中线部位亦没有清晰可见的微丝累积。(3)晚末期Ⅰ,可育系花粉细胞在形成细胞板的部位是线性的、平滑的,成膜体微丝消失,而不育系花粉细胞在形成细胞板的部位形成了很大的缝隙,同时,可育系胼胝质在细胞板处的沉积比较平滑,而不育系胼胝质在细胞板处的沉积较可育系相比缺乏,并且是褶皱的、有裂纹的。(4)四分体时期,可育系花粉可见围绕细胞核的辐射状微丝,不育系花粉细胞中微丝呈模糊状态,并且不育系中胼胝质染色的整体荧光强度较可育系减弱。利用实时荧光定量PCR技术分析肌动蛋白解聚因子TaADF和类葡聚糖合成酶TaGSL在减数分裂期的相对表达量,结果发现,不育系中TaADF的相对表达量是可育系的4.28倍,由于TaADF表达量上调,加剧了细胞内微丝解聚,微丝结构受到破坏,同时不育系中TaGSL表达量下降,只有可育系的0.83倍,胼胝质的沉积也受到影响。【结论】TaADF在不育系中上调表达,破坏了细胞内微丝的正常结构,使微丝不能正常行使其功能,进而可能导致花药发育中与育性相关的某些代谢通路等受到影响。与此同时,微丝结构的破坏导致细胞板形成出现异常也可能是引起胼胝质在细胞板处沉积受到影响的一个重要原因。因此,微丝和胼胝质的异常变化与化学杂交剂SQ-1诱导的生理型雄性不育密切相关。     

西伯利亚白刺肌动蛋白基因的分离与特性分析

利用兼并PCR及RACE技术克隆了西伯利亚白刺的肌动蛋白基因(Nitraria sibirica Actin, NsAct),并对其基因结构和表达特性进行了分析。所克隆的NsAct cDNA全长序列为1 831 bp,包含1 134 bp的开放阅读框,编码377个氨基酸;基因组DNA全长序列为2 913 bp,包含5个外显子和4个内含子。系统进化分析结果显示,NsAct与其他植物的肌动蛋白基因具有较高的同源性,与芒果(无患子目)亲缘关系最为接近。基因表达特性分析的结果显示,该基因在根、茎、叶中的表达量基本一致;在干旱、盐、低温及外源脱落酸胁迫下,表达量无明显变化,这些结果验证了该基因作为分子内标的可靠性。     

Effects of Danshensu on TGF-β1/Smads signaling pathways in rats with pulmonary fibrosis

AIM: To study the preventive and curative roles of Danshensu (DA) in bleomycin (BLM)-induced pulmonary fibrosis in rats. METHODS: Pulmonary fibrosis was induced in SD rats by intratracheal instillation of BLM. The rats were intraperitoneally injected with dexamethasone (1 mg·kg-1·d-1, DXM group), DA (15 mg·kg-1·d-1, DA group), or physiological saline (2 mL·d-1, BLM group). Normal controls (NC group) received physiological saline both intratracheally and intraperitoneally. At the 28th day after modeling, the histological changes of the lungs were evaluated by hematoxylin-eosin (HE) and Masson’s trichrome staining. The protein levels of α-smooth muscle actin (α-SMA) in the lung tissues were detected by the method of immunohistochemistry. The mRNA expression of transforming growth factor beta 1 (TGF-β1), Smad3 and Smad7 was assessed by real-time fluorescence quantitative PCR. RESULTS: Compared with BLM group, the degree of inflammation and fibrosis of the lung in DA group was obviously reduced, and so was the expression of α-SMA in the lung tissues. The mRNA expression of TGF-β1 and Smad3 in the lung tissues of the rats decreased and the mRNA expression of Smad7 increased. CONCLUSION: DA alleviates BLM-induced pulmonary fibrosis in rats in the early stage by inhibiting the expression of TGF-β1/Smad3 and stimulating the expression of Smad7 in the lung tissues.