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1.
Cuticular proteins(CPs) are major components of the insect cuticle-associated organs such as integument and wings, although the importance of CPs for wing development and function in hemimetabolous insects remains understudied. In the present study, a wing cuticular protein LmACP8 was identified from Locusta migratoria, which belongs to the RR-2 subfamily of cuticular protein RR consensus(CPR) chitin-binding proteins. LmACP8 was mainly expressed in the wing pads and showed high expression levels before ecdysis of third-, fourth-, and fifth-instar nymphs, with its encoded protein located in the procuticle of wing pads and adult wings. Depletion of LmACP8 by RNA interference markedly reduced the amount of its protein, which consequently caused abnormal wing morphogenesis in the transition from nymph to adult of L. migratoria. We further demonstrated that the abnormal morphogenesis was caused by severe damage of the endocuticle in the wings. LmACP8 was suppressed by 20-hydroxyecdysone(20 E) in vivo, however, its expression was significantly up-regulated after knocking down the hormone receptor gene LmHR39. Thus, the LmACP8 that is negatively regulated by the LmHR39-mediated 20 E signaling pathway is involved in wing development during the nymph to adult transition.  相似文献   
2.
The present study investigated the replacement of soybean meal with combinations of two or three alternative protein sources in diets for pond‐raised hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. Alternative protein sources evaluated included cottonseed meal, distillers dried grains with solubles (DDGS), peanut meal, and porcine meat and bone meal (PMBM). Hybrid catfish fingerlings with a mean initial weight of 35 g/fish were stocked into 25 earthen ponds (0.04 ha) at a density of 14,826 fish/ha. Fish were fed once daily to apparent satiation for 166 d. No significant differences were observed for total diet fed, net yield, weight gain, survival, carcass yield, fillet yield, or fillet proximate composition among dietary treatments. Results show soybean meal may be completely replaced by combinations of cottonseed meal and one or two other alternative protein sources including DDGS, peanut meal, and PMBM in the diet without markedly affecting production and processing characteristics and fillet proximate composition of pond‐raised hybrid catfish. These alternative diets may be used during foodfish production when prices are favorable.  相似文献   
3.
经过蛋白质着色动力学的研究,发现蛋白质着色的行为遵循数学模型Y=aX^b。在pH2-6范围内,蛋白质上染料随染溶pH的下降而上升,在15-30℃温度范围内,蛋白质上染率随温度上升略有提高,当温度超过30℃时,蛋白质上染率逐渐下降。染浴中添加稀土对蛋白质有较强的促染效果,其实质是染浴中蛋白质首先对稀土高价阳离子进行结合,再通过高价阳离子对色素进吸附。  相似文献   
4.
青海血蜱不同发育阶段蛋白分析   总被引:2,自引:0,他引:2  
考虑到不同发育阶段蛋白多肽及抗原特性方面的差异,本实验利用SDS-PAGE和Westernblotting对青海血蜱的卵、幼蜱、若蜱、成蜱的蛋白进行了分析。SDS-PAGE结果显示,卵出现了7条主带,幼蜱出现了16条主带,若蜱出现了14条主带,成蜱出现了12条主带。它们的蛋白多肽在数量、含量和分子量上存在差异,共同带只有4条,但相邻发育阶段之间的共同带较多。用感染羊血清和免疫羊血清作免疫印迹时,感染羊血清在分子量5.6万处有明显的反应带,免疫羊血清在分子量9.7万处有明显的反应带。  相似文献   
5.
甘肃滩羊血红蛋白(Hb)及红细胞蛋白质(Ep)多态性的研究   总被引:6,自引:3,他引:3  
运用聚丙烯酰胺凝胶电泳技术(PAGE)对甘肃滩羊产区皋兰、景泰及靖远3县285只滩羊的血红蛋白(Hb)基因座、红细胞蛋白质-1(Ep-1)和红细胞蛋白质-2(Ep-2)基因座多态性进行了检测,结果发现甘肃滩羊Hb基因座存在3种基因型HbAA、HbAB、HbBB,它们受HbA和HbB两个共显性等位基因控制,其中HbB和HbBB在3个群体中均占优势;本研究未在Ep-1和Ep-2基因座上检测到多态性,它们均呈现单态。  相似文献   
6.
A review of the current literature available on feline serum proteins is presented. Early studies concentrated on comparative aspects of species variations in the electrophoretic pattern. The feline electrophoretogram was divided into five basic regions: albumin, alpha-1, alpha-2, beta and gamma. Different subdivisions of these areas were recognized depending on the support medium used. Current papers have compared the relative migration distances of each globulin peak to the migration of albumin. This "Rf" value enables reliable peak identification. To date, no data exists identifying the individual proteins responsible for the peaks in the alpha and beta regions. The only feline globulin to be studied is haptolobin; however its precise location on the electrophoretic strip was not identified.  相似文献   
7.
The induction of a hypersensitive reaction in Samsun NN tobacco by tobacco mosaic virus (TMV) at 20°C leads to the development of both localized and systemic acquired resistance, and is associated with the appearance of pathogenesis-related proteins (PR's) and large increases in peroxidase activity and ethylene production. Salicylic acid (SA) induced a similar resistance in treated plant parts and occasionally also in untreated upper leaves of plants of which three lower leaves had been injected. SA also induced the same four PR's, but these were confined to the treated leaves. Thus, the connection between the presence of PR's and the reduction of TMV multiplication and spread may not be direct.In contrast to TMV, SA did not stimulate ethylene production and hardly increased peroxidase activity. Induction of acquired resistance and PR's by SA developed equally well at 20°C and at 32°C. However, pricking leaves with needles moistened with the ethylene-releasing compound ethephon mimicked TMV infection in inducing acquired resistance and PR's in both treated and untreated leaves at 20°C, but not at 32°C. Ethephon increased peroxidase activity at both temperatures, but only at 20°C dit it induce changes in both the anodic and the cathodic isoenzymes that were similar to those induced as a result of TMV infection. SA induced PR's and reduced TMV multiplication in Samsun tobacco, and inhibited virus spread in Samsun NN at 32°C.These observation indicate that neither the induction of PR's, nor the development of acquired resistance is temperature-sensitive. On the other hand, the effects of ethephon are temperature-sensitive in the same way as the hypersensitive response to TMV. It can thus be hypothesized that ethylene, produced naturally during the hypersensitive reaction of tobacco to TMV, leads to the temperature-sensitive synthesis or release of a presumably benzoic acid-type compound that functions as the natural inducer of PR's and acquired resistance. Although vanillic acid has been shown to accumulate in hypersensitively reacting tobacco leaves, it produced none of the effects of SA, and thus cannot be the natural inducer.Samenvatting Inductie van een overgevoeligheidsreactie in Samsun NN-tabak door tabaksmozaïekvirus (TMV) bij 20°C leidt tot de ontwikkeling van een verworven resistentie die zowel lokaal als systemisch werkzaam is, en gaat samen met het verschijnen van pathogenesis-related proteins (PR's) en sterke toename in de activitieit van peroxidase en de produktie van ethyleen. Salicylzuur (SA) induceerde een vergelijkbare resistentie in behandelde plantedelen en af en toe ook in niet behandelde bovenbladeren van planten waarvan drie onderbladeren waren ingespoten. SA induceerde ook dezelfde vier PR's, maar deze waren beperkt tot de behandelde bladeren. Er bestaat dus geen directe samenhang tussen de aanwezigheid van PR's en de remming van de vermeerdering en uitbreiding van TMV in de plant.In tegenstelling tot TMV stimuleerde SA de ethyleenproduktie niet en verhoogde het de peroxidaseactiviteit nauwelijks. Inductie van verworven resistentie en PR's door SA trad even goed op bij 32°C als bij 20°C. Net als infectie met TMV leidde aanprikken van bladeren met naalden die gedoopt waren in een oplossing van ethefon — waaruit in het blad ethyleen vrijkomt — echter tot inductie van verworven resistentie en PR's in zowel behandelde als onbehandelde bladeren bij 20°C, maar niet bij 32°C. Ethefon verhoogde de peroxidaseactiviteit bij beide temperaturen, maar alleen bij 20°C induceerde het veranderingen in zowel de anodische als de kathodische isoënzymen die vergelijkbaar waren met die welke geïnduceerd werden als gevolg van infectie met TMV. SA induceerde PR's en verminderde de vermenigvuldiging van TMV in Samsun tabak, en remde de uitbreiding van het virus in Samsun NN bij 32°C.Deze waarnemingen tonen dat noch de inductie van PR's, noch de ontwikkeling van verworven resistentie een temperatuurgevoelig proces is. Daarentegen zijn de effecten van ethefon op dezelfde wijze temperatuurgevoelig als de overgevoeligheidsreactie op TMV. Men kan daarom veronderstellen dat ethyleen, dat op natuurlijke wijze geproduceerd wordt tijdens de overgevoeligheidsreactie van tabak op TMV, aanleiding geeft tot een temperatuurgevoelig proces, namelijk de synthese of het vrijkomen van een verbinding, vermoedelijk een benzoëzuurderivaat, dat fungeert als de natuurlijke inductor van PR's en verworven resistentie. Hoewel is aangetoond dat vanillinezuur zich ophoopt in overgevoelig reagerende tabaksbladeren, veroorzaakte deze verbinding geen enkel van de effecten van SA. Vanillinezuur kan dus niet de natuurlijke inductor zijn.  相似文献   
8.
South-Westerm blot mapping是一种结合Western blotting和Southern blotting某些特点的方法.本文介绍用其成功地观察到锥虫核蛋白中DNA结合蛋白的情况,并对一个分子量在40000左右、于较严谨条件下与DNA结合的核蛋白进行了特性鉴定.该蛋白等量地存在于锥虫的前循环期和血液期,对双链DNA有较大的亲和力,并能与酵母菌复制起始片段结合.本文还介绍了锥虫细胞核的提取技术和核蛋白的制备技术.  相似文献   
9.
AIM:To manufacture recombinant protein of the highly conserved domain in human bone morphogenetic protein-1(BMP-1) using gene engineering methods as antigen for making wide spectrum antibody to BMP-1.METHODS:We analyzed the gene sequences and protein structures of BMP-1 and its related proteins, and chose a highly conserved fragment as target gene. Total RNA was prepared from human osteosarcoma cell line Saos-2, then the target gene was amplified with RT-PCR. The PCR product was cloned into prokaryotic expression vector pMAL c2 to get recombinant vector BMP-1(322-588aa)-pMAL c2. After transforming the recombinant plasmid into DH5-alpha and screening, several prositive clones were got for sequencing. Finally the transformed cells was induced with IPTG to get fusion protein.RESULTS:The BMP-1 gene fragment was successfully cloned into vector pMAL c2, and was able to express efficiently with IPTG inducement. The amount of expressed fusion protein is about 66%-72% in total volume of bacterial proteins.CONCLUSIONS:The recombinant protein contains several key domains(2 CUB domains and 1 EGF domain), which are shared by BMP-1 and its related proteins. Specific wide spectrum antibody to human BMP-1 and its related proteins may be generated with this recombinant protein antigen.  相似文献   
10.
AIM:To investigate the effect of the heat shock response on the reperfusion arrhythmias(RAs) and the possible mechanism involved. METHODS:Fifty-five Sprague Dawley rats were randomly divided into 2 groups: the heat shock group (group H,n=29) and the control group (group C,n=26). The rats in group H were preconditioned with heat shock 24 hours before, and that in group C were not. The hearts of 16 rats in group H and 16 in group C were exercised and mounted on a non-circulating Langendorff perfusion apparatus and perfused retrogradely with modified K-H buffer and mimic ischemia/reperfusion was applied. Additionally, conventional intracellular microelectrode techniques were used for recording such electrophysiological parameters as resting potential(RP), action potential amplitude(APA), over shot(OS), maximum depolarization velocity(Vmax) of the hearts of other 13 rats in group H and 10 in group C. RESULTS:①Prior heat stress significantly decreased reperfusion arrhythmia. ②The amount of CK release in the effluent in group H was much less than that in group C. ③Myocardial HSP70 content was elevated significantly in group H. ④Heat stress significantly increased myocardial anti-oxydases activity and decreased lipid peroxydative products. Additionally, heat stress significantly reduced the Vmax of action potential. It indicated that rapid Na+ channel of papillary muscles may be inhibited by heat shock. The degree of change of Vmax after ischemia in H group was significantly less than that in group C. And the time of reperfusoin with Tyrode's solution till the action potential appeared as large as that before perfusion with mimic ischemic solution is shorter in group H than in group C. CONCLUSION:Heat shock pretreatment markedly reduces ischemia/reperfusion-induced injury of heart and ventricular arrhythmias in rats and this effect may be associated with the inhibition of rapid Na+ channel of papillary muscles by heat shock and the increase in myocardial HSP70 and anti-oxydase activity.  相似文献   
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