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991.
甘蓝Ogura胞质雄性不育基因的RAPD标记筛选*   总被引:1,自引:0,他引:1  
有关利用RAPD[1]技术进行分子标记的研究报道很多,如王俊霞等[1]对甘蓝型油菜Pel CMS育性恢复基因和王晓武等[2]对甘蓝的一个显性核雄性不育基因均进行了RAPD标记.我们经过多年的选育,已经成功把外源胞质雄性不育基因转育到甘蓝自交不亲和系上,现已成功选育出不育性稳定和经济性状优良的甘蓝雄性不育系.为了更深入的研究其不育机理,利用RAPD分子标记技术对其不育基因进行了标记,为以后开展甘蓝杂优育种提供标记基因打下基础.  相似文献   
992.
Bactericidal/permeability-increasing protein (BPI) has a strong effect on sterilization (mainly for G- bacteria),neutralizing the activity of lipopolysaccharide (LPS) and enhancing the phagocytosis of mononuclear cells and neutrophils to pathogenic bacteria.The biological functions of BPI have been researched widely in recent years,which is known as "super antibiotic" and has been explored by many scholars as a candidate gene for resistance.This author summarized the research progress and application prospect of the BPI gene in the pig resistant breeding by introducing the structure,biological function of BPI gene and its relationship with the resistance,which was aimed to provide theoretical references and basis for the function research of pig BPI gene and its practical application in resistance breeding in future.  相似文献   
993.
This study was aimed to prepare canine parvovirus (CPV) VP2 protein polyclonal antibody.The recombinant expression vector pET28a-CPV-VP2 was constructed and transfromed into E.coli BL21 (DE3),the expression of recombinant proteins was induced by IPTG from which the fusion protein was identified by SDS-PAGE.The target protein was purified and emulsify with adjuvant,the prepared immunogen was inoculated into rabbit by subcutaneous injections to prepare of VP2 protein specific polyclonal antibody.The immuno-activity,titers,neutralization titers of the prepared polyclonal antibody were determined by immunoperoxidase monolayer assay (IPMA).The results showed that the expressed recombinant protein VP2 (rVP2) existed in the form of inclusion body with a molecular weight of 72 ku.The prepared polyclonal antibody titer was 1 600 dilution,the virus titer was 107 TCID50/mL,the neutralizing titer was 1∶2 884.The antibodies showed specific reaction with CPV.In conclusion,rVP2 specific polyclonal antibody showed wonderful immunocompetence,specificity and neutralizing activity,providing foundation for the development of genetic vaccine and clinical therapeutic method.  相似文献   
994.
The study aimed to explore the mRNA expression pattern of insulin-like growth factor binding protein-5 (IGFBP-5) gene in different tissues of Kazakh and Yanqi horses.The expression of IGFBP-5 gene in different tissues of heart,liver,spleen,lung,kidney,small intestine,large intestine,cecum,intercostal muscles,longissimus dorsi muscles,brachialis muscle and gluteus in two horses were detected by Real-time quantitative PCR and compared the mRNA expression in the same tissues of two breeds.The results showed that the expression of IGFBP-5 in longissimus dorsi muscle and brachialis muscle of two breeds were significantly higher than other tissues including heart,liver,spleen,lung,kidney,small intestine,large intestine and cecum (P<0.05),and was the lowest in large intestine.The expression of IGFBP-5 in kidney,small intestine,large intestine,cecum,longissimus dorsi muscle and brachialis muscles of Yanqi horse were higher than in the same part of Kazakh horse,and among those in longissimus dorsi muscle and large intestine of Yanqi horse were extremely significantly higher than in the same part of Kazakh horse (P<0.01),and in small intestine and cecum of Yanqi horse were significantly higher than in the same part of Kazakh horse (P<0.05).The test was for further researching the biological function of IGFBP-5 gene,and it could provide a theoretical basis for genetic improvement of production performance of horse in our country.  相似文献   
995.
In order to study and analyze L1 gene of bovine papillomavirus(BPV)in Guizhou province,the L1 gene of BPV-GZ01 strain was amplified,cloned and sequenced using bioinformatic softwares and methods,and the secondary structure,tertiary structure,B-cell preponderant epitope,conserved domains analysis, transmembrane domain and signal peptide of L1 gene were predicted.The results showed that the length of L1 gene was 1 494 bp,encoding 497 amino acids.The L1 gene of BPV-GZ01 strain shared an amino acid identities of 98.6%,99.4%,98.4%,94.4% and 91.3%,and a nucleotide identities of 99.1%,99.8%,99.4%,87.6% and 82.8% with those of BPV2,BPV2-SW01,BPV2-AKS01,BPV13 and BPV1 strains,respectively.The results of phylogenetic tree analysis indicated that there was a close relationship between BPV-GZ01 and BPV2-SW01 strains.The prediction of secondary structure of L1 protein indicated that the random coil,extended strand and alphahelix took a higher percentage.The L1 protein was supposed contain 6 potential antigen epitopes.And no transmembrane domains and no signal peptide were found.The tertiary structure of L1 protein was curved spiral structure.These results provided a theoretical basis for immunologic diagnosis and further research of nucleic acid vaccine of BPV.  相似文献   
996.
To investigate the epidemic situation of H6N6 subtype avian influenza virus (AIV) in Guizhou province,A/duck/Guizhou/013/2014 was isolated from Sansui duck in live poultry market of Guizhou in 2014,the hemagglutinin (HA) and neuraminidase (NA) genes of DK/GZ/14 were subjected to clone and sequence analysis.The results showed that HA gene had the highest nucleotide homologies (97.5%) with the duck-origin H6N6 subtype AIV isolated from Eastern China in 2009,and the strains of HA gene proteolytic cleavage sites was P-Q-I-E-T-R-G,which accordeol with the molecular characteristic of low pathogenic AIV (LPAIV).However,NA gene of A/duck/Guizhou/013/2014 had the highest nucleotide homologies (98.2%) with the duck-origin H6N6 subtype AIV isolated from Fujian in 2007.The phylogenetic tree showed that A/duck/Guizhou/013/2014 and Hunan strains located in the same branch,while three duck-origin H6N6 subtype AIV isolated from Guizhou in 2007 and A/duck/Guizhou/013/2014 located in the different branch for HA and NA genes in genetic evolution,which suggested that A/duck/Guizhou/013/2014 was far with the local H6N6 subtype.The results also clearly indicated that duck-origin H6N6 subtype AIV had genetic diversity in duck population in Guizhou.  相似文献   
997.
To establish a rapid assay for Listeria monocytogenes(LM) detection,a Real-time PCR method was developed targeting iap gene of LM.The results showed that the test for 15 bacteria strains,only LM was positive,indicated that the method had high specificity.In addition,the sensitivity of Real-time PCR was 6.5 CFU/mL.Stability and reproducibility of the test showed that the coefficient of variation for the same sample repeat the Ct values were less than 2%.Furthermore,a total of 3 positive samples for LM were detected from 139 clinical samples by the method,which was in accordance with the testing result by GB 478930-2010 standard detection protocol.Therefore,the Real-time PCR method provides a novel rapid,sensitive and good repeatability detection method for LM infection.  相似文献   
998.
To study the expression pattern of THBS3 gene in different tissues and during skeletal muscle development, the THBS3 gene expression in different tissues and skeletal muscles during prenatal periods (33, 45, 65, 70 and 90 d) and postnatal periods (0, 9, 30, 60, 120 and 160 d) from Landrace and Tongcheng pigs were detected by Real-time quantification PCR.The results showed that THBS3 gene widely expressed in all tissues examined, exhibiting similar spatial expression patterns with expression peaks in lung in both pig breeds except in stomach and intestine.Moreover, although THBS3 gene showed a significant higher expression level in gestation than after birth in Landrace and Tongcheng pigs (P<0.05), it exhibited different expression patterns between Landrace and Tongcheng pigs, the expression peak was detected at gestation day 45 in Landrace pig, while was detected at gestation day 65 in Tongcheng pig.The results suggested that THBS3 gene involved in skeletal muscle growth and development in pigs, as well as the regulation of asynchronization of skeletal muscle development in different pig breeds.  相似文献   
999.
This study was aimed to understand the characteristics of length polymorphism with repeat sequence of keratin associated protein 1 (KAP1) family genes in yak. KAP1 family genes of yak and cattle were sequenced, and compared with sheep KAP1 family gene sequences. The results showed that cattle KAP1 family genes were located in chromosome 19, according to location of sheep KAP1 family genes in the chromosome and similarity with cattle KAP1 family genes, renaming the cattle KAP1 family (according to the gene location of chromosome) B2D, B2A, KAP1-1 and B2C genes into KAP1-4, KAP1-1, KAP1-2 and KAP1-3 gene, respectively. KAP1 family genes in the 3'and 5' flank were highly conserved, the difference between family genes mainly in the the repeat sequence region, which yak KAP1 to KAP4 genes were found 30 bp length polymorphism. There were B(CCQTS)A1(CCQPT) repeat sequence and a new repeat sequence C(SIQTS). The results indicated that the repeat sequence was the key of the polymorphism of KAP1 family genes, which might be relate to combination with keratin protein.  相似文献   
1000.
正柑桔黄龙病(HLB)对美国佛罗里达州(以下简称佛州)柑桔产业产生了毁灭性的影响,据估计,该州目前80%以上的柑桔树被感染,2014/2015产季佛州柑桔产量创50年来新低。占佛州柑桔种植面积95%以上的甜橙和葡萄柚更易感染柑桔黄龙病。选育抗黄龙病品种势在  相似文献   
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