麝香百合液泡膜水孔蛋白基因LlTIP2的克隆及生物信息学分析

水孔蛋白是位于质膜和液泡膜等生物膜上主要负责水分跨膜运输的通道蛋白,属于膜主要内在蛋白(major intrinsic proteins,MIP)超家族.采用RT-PCR和RACE法从麝香百合(Lilium longiflorum)叶片克隆得到1个液泡膜内在蛋白(tonoplast intrinsic proteins,TIPs)基因的全长cDNA序列,命名为LTIP2(GenBank登录号:JN085950).该基因cDNA全长986 bp,包括208bp的3’-非翻译区,744 bp开放阅读框以及34 bp的5’-非翻译区,共编码247个氨基酸.由L1TI P2推导的氨基酸序列具有2个高度保守的水孔蛋白NPA (Asn-Pro-Ala)基序以及MIP的特征序列SGGHVNPAVTFG.同源性分析表明,LITIP2氨基酸序列与陆地棉(Gossypium hirsutum)、大麦(Hordeum vulgare)、黑麦草(Lolium perenne)和小麦(Triticum aestivum)等植物TIP2的同源性分别达77％、74％、73％和72％.系统进化树分析表明LlTIP2属于液泡膜水孔蛋白TIP2亚类新成员.     

Effect of renal denervation by radiofrequency catheter ablation on expression of aquaporins in dog kidneys

AIM: To investigate the effect of renal denervation (RDN) by radiofrequency catheter ablation on the expression of aquaporins (AQP) in dog kidneys.METHODS: Adult Chinese Kunming dogs (n=12) were randomly divided into RDN group and control group (6 for each group). The dogs in RDN group underwent bilateral RDN using radiofrequency catheter ablation, and radiofrequency catheter was positioned in bilateral renal artery without ablation in control group. The levels of norepinephrine (NE) and AQP1~3 in the renal tissues were detected 1 month after RDN, and blood pressure (BP) measurements were performed at baseline and 1 month after RDN.RESULTS: The level of NE in RDN group was significantly lower than that in control group (P<0.01). The expression of AQP1~3 in the renal cortex and medulla was lower in RDN group than that in control group. RDN also caused a substantial BP reduction (P<0.05). CONCLUSION: RDN substantially decreases the tissue levels of NE and AQP in dog kidneys, and also decreases BP significantly, which might be involved in the mechanism of BP reduction by RDN. Renal sympathetic nerve plays an excitatory role in the regulation of AQP in the kidney.     

Aquaporins in lung

Aquaporins (AQPs) is a novel family of membrane protein whichis in charge of the transportation of water across the membranes. It has been testified that AQPs may be related to many physiologicalfunctions and pathophysiological disorders. In lung, 6 subtypes of AQPs were found, 4 of which have been located in certain tissue. AQP1, AQP3, AQP4 and AQP5 are located in upper respiratory tract and may contribute to the mucus production, bronchial moisturizing and gland secretion. AQP1 and AQP5 are located in lower respiratory tract and may participate in directing the water movement across the blood-gas barrier. AQPs in natal lung may be an important factor to accelerate the reabsorption of the lung liquid. In adult, some diseases such as asthma, pulmonary edema, adult respiratory distress syndrome, which have been considered unbalanced water movement, may be also concerned with AQPs. The relationship between lung edema and AQPs have not been elucidated in details. It should be verified how AQPs work in more organs and tissues as well as in some diseases.     

龙眼水通道蛋白基因(DLPIP1)的克隆与表达分析

应用蛋白质组学研究低温胁迫下龙眼叶片蛋白质组变化时,发现PIP1蛋白在龙眼低温胁迫中上调表达。应用RACE技术克隆龙眼水通道蛋白基因全长cDNA,命名为DLPIP1,基因登陆号为JN572691,长度为1 132 bp,包括1个900 bp的开放阅读框,编码299个氨基酸序列,同源性分析表明,DLPIP1在21个不同植物中的一致性为90%~93%。应用生物信息学软件对DLPIP1氨基酸序列分析表明,含有7个跨膜区,有2个NPA单元,其氨基酸残基与MIP家族蛋白保守区序列完全一致。氨基酸序列比对发现,该序列与其他物种PIP质膜水通道蛋白氨基酸序列有很高的同源性。利用实时荧光定量技术对DLPIP1在低温胁迫下不同组织表达谱分析表明,DLPIP1在龙眼根、茎、叶中都有表达,在根中的表达量最高,其次是茎和叶。DLPIP1在低温胁迫时,随着低温胁迫时间的延长而发生变化。这说明DLPIP1蛋白在龙眼低温逆境过程中起作用。     

水稻水通道蛋白OsPIP2-6的亚细胞定位研究（摘要）

[目的]探讨水稻水通道蛋白OsPIP2-6的亚细胞定位。[方法]克隆了水稻中的重要通道蛋白OsPIP2-6基因,构建了瞬时表达载体,通过基因枪法在洋葱表皮中进行瞬时表达,并通过激光共聚焦显微镜进行了观察。[结果]水稻水通道蛋白OsPIP2-6主要定位在细胞质膜上,证明了OsPIP2-6是个水通道蛋白。[结论]为植物水通道蛋白的深入研究提供了理论依据。     

仔猪水通道蛋白基因的克隆及断奶应激对其在胃肠道组织mRNA表达的影响

水通道蛋白(AQP)作为一种膜转运蛋白,对于调控肠道组织的水分子转运具有重要作用。本实验利用同源序列克隆法设计引物,从仔猪(Susscrofa)的消化道组织中克隆AQPs家族基因(AQP2~AQP11)(GenBank登录号分别为EU636238、EU161094、EU165525、EU192130、EU620575、EU024116、EU220426、EU220427、EU582021和EU220425),并对其进行生物信息学分析。采用荧光定量PCR研究断奶应激对于仔猪胃肠道组织中AQP1、AQP3、AQP8和AQP11的mRNA表达影响。生物信息学分析发现,猪AQPs家族基因含有高度保守的天冬酰氨-脯氨酸-丙氨酸(NPA)结构序列,基因表达分析发现,断奶组仔猪的AQP1基因在十二指肠、回肠和结肠组织的mRNA表达量与对照组相比显著上调(P<0.05);AQP3基因在胃和小肠组织的mRNA表达有显著上调(P<0.05);AQP8基因在胃和回肠组织中mRNA表达有显著上调(P<0.01),在其他组织中没有显著差异;AQP11基因在空肠组织的mRNA表达量显著上调了1.7倍(P<0.05)。这些研究结果表明,AQP基因可能在断奶应激引起的仔猪肠道腹泻中发挥重要作用。     

水稻水通道蛋白OsPIP2-6的亚细胞定位研究

[目的]探讨水稻水通道蛋白OsPIP2-6的亚细胞定位。[方法]克隆了水稻中的重要通道蛋白OsPIP2—6基因,构建了瞬时表达载体,通过基因枪法在洋葱表皮中进行瞬时表达,并通过激光共聚焦显微镜进行了观察。[结果]水稻水通道蛋白OsPIP2-6主要定位在细胞质膜上,证明了OsPIP2-6是个水通道蛋白。[结论]为植物水通道蛋白的深入研究提供了理论依据。     

Effect of inhaled nitric oxide on aquaporin expression in newborn rat lung in acute hyperoxic lung injury

AIM:To investigate the effect of inhaled nitric oxide on aquaporin expression and alveolar epithelial fluid transport in newborn rats with acute hyperoxic lung injury. METHODS:32 newborn SD rats were randomized to breathe for 48 h room air (C), >95%O₂ (O), >95%O₂+10^-5 NO (NO only in the first 24 h, ONO), room air + NO (CN). Then, the rats were killed, the lung wet-to-dry weight ratio (Q_W/Q_D), the histology, and AQP1, AQP5, α₁-NKA, α-ENaC mRNA expressions in the lungs were measured. RESULTS:Compared with C group, the Q_W/Q_D in O group significantly increased (P<0.01), and AQP1 mRNA expression decreased significantly (P<0.01). Compared with O group, ONO group had a lower level of Q_W/Q_D (P<0.05), and AQP1 mRNA expression increased (P<0.05). AQP5 mRNA expression in all groups remained unchanged. CONCLUSION:In newborn rats with acute hyperoxic lung injury, inhaled 10-5 nitric oxide for 24 h may attenuate lung edema and increase AQP1 mRNA expression, suggesting that inhaled 10^-5 nitric oxide for 24 h may promote the AQP1 expression in lung in this model of acute lung injury.