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931.
Twenty feline neoplasms were sequenced in the region from exons 5 to 8 for the presence of tumour suppressor gene p53 mutations. In a spindle cell sarcoma of the bladder, a missense mutation (codon 164 AAGGAG, lysineglutamic acid) in exon 5 was detected. In a pleomorphic sarcoma, a 23 bp deletion involving the splicing junction between intron 5 and exon 6 was observed. In a fibrosarcoma, a 6 bp deletion of p53 covering 2 bp of exon 7 and 4 bp of intron 7, including the splicing junction, was found. The study demonstrates three new p53 mutations in different types of sarcomas in cats. 相似文献
932.
抗菌肽基因导入桑树获得抗病转基因植株 总被引:11,自引:2,他引:9
用携带抗菌肽基因的农杆菌处理桑子叶,在含有羧苄青霉素(Cb)400~500mg/L和卡那霉素(Km)20mg/L的MS培养基上,有32.4%的子叶产生了不定芽;66.5%的不定芽在含有Cb300mg/L和Km30~40mg/L的培养基中,正常生长成2~3cm高的新稍;新梢在含Cb50mg/L和Km10mg/L的生根培养基中有72.6%形成完整根系。3次转化共获得12个株系55株KmR植株。不同株系桑苗叶片DNA点杂交分析显示,7个株系有阳性杂交信号。KmR株系桑苗的抗病性测定显示,5个株系共14株桑苗对青枯病具有较强抗性. 相似文献
933.
动物性别决定的分子机理及性别鉴定与控制新技术 总被引:12,自引:0,他引:12
哺乳动物中位于Y染色体短臂临界区域的SRY基因启动雄性性状的发育。该基因在生殖腺脊中的表达可激发下游基因MLS的转录,引起缪氏体抑制物和睾酮分泌,促使睾丸组织器官的发育。针对该基因制备特异探针或产该区域片段得到引物对就可用FISH或PCR准确,快速鉴定出植入母体前的胚胎性别,以及对精子筛选分离的结果作出准确评价。与PCR相比,FISH技术更具检测优势。 相似文献
934.
QU Chun-feng LI Sheng LI Hui DU Feng-jiao LEI Wei WU Zhu-lian LI Xiang-ping SHI De-shun 《中国畜牧兽医》2015,42(7):1621-1629
Cloning buffalo AQP9 gene and analyzing its expression in buffalo tissues.A pair of primers was designed according to the released bovine AQP9 sequences in GenBank,which was used to clone buffalo AQP9 gene.The AQP9 gene was amplified by RT-PCR,whose nucleotide sequence and protein structure were analyzed by bioinformatics methods.The expression of AQP9 in buffalo tissues was assayed by Real-time quantitative PCR.The expression of AQP9 gene in buffalo ovary and testis tissue was detected by immunohistochemical staining method.The results showed that the cloned ORF length of buffalo AQP9 gene was 888 bp,which coded 295 amino acids.The results of multiple sequence comparison showed that the nucleotide sequence of buffalo AQP9 shared 99%,90%,97% and 88% homologeous compared with that of Bos taurus,Sus scrofa,Ovis ariessis and Homo sapiens,respectively,while shared 99%,86%,97%,83% homologeous for amino acids,respectively.Phylogenetic tree analysis indicated that AQP9 gene was highly conservative in the evolutionary process.Real-time quantitative PCR results showed that AQP9 gene expressed in buffalo liver,lung,brain,skin,testis and ovary tissues with different levels,had the most abundant expression in liver,followed by in skin and testis,less observed in lung and ovary.The results of immunohistochemical staining showed that the expression of AQP9 protein varied with the development of buffalo ovarian tissue,and gradually enhanced with follicle development.In testicular tissue,AQP9 protein expressed in spermatocyte and leydig cells of developmental stage testis.These results indicated that we had successfully cloned buffalo AQP9 gene sequences.The expression and its function of AQP9 in buffalo ovaries and testes might play an important role in follicle development and spermatogenesis. 相似文献
935.
稻瘟病菌T-DNA插入的突变表型分析 总被引:1,自引:0,他引:1
PCR技术检测28个形态发育和致病性相关T-DNA插入突变体,结果所有突变体均含磷酸转移酶基因序列。对这些突变体展开进一步生物学性状观察,发现15个颜色异常,8个菌落生长缓慢,2个分生孢子形态异常,2个附着胞形态异常,3个不能形成附着胞。致病性测定结果,9个突变体完全不能导致抗瘟(C101)和感瘟(日本晴)水稻苗致病,病害级别均为0级。用标准菌株1528和P131测定突变体有性世代的形成能力,结果发现, Y34-0211、Y34-1469和Y34-0635 3个突变体完全丧失产生有性世代的能力。 相似文献
936.
论述了疱疹病毒UL34基因的序列特点、编码蛋白结构特点、基本功能以及它与UL31蛋白、Us3蛋白、动力蛋白、核纤层蛋白的相互作用。表明,UL34基因对病毒的早期包装、成熟和出芽以及对UL31蛋白和核纤层蛋白在感染细胞中的正确定位都具有重要作用。 相似文献
937.
938.
M. Carof S. De Tourdonnet Y. Coquet V. Hallaire & J. Roger-Estrade 《Soil Use and Management》2007,23(3):230-237
We studied soil hydraulic conductivity (K) and porosity in five combinations of soil tillage and cover crop management systems. Treatments were winter wheat (Triticum aestivum L.) grown on a conventionally tilled soil (CT), on a no‐till soil (NT), and on an NT with three different cover crops: red fescue (Festuca rubra L.; Fr), bird's‐foot‐trefoil (Lotus corniculatus L.; Lc) and alfalfa (Medicago sativa L.; Ms). Measurements were made on a loamy soil in Grignon, France, in November 2004, May 2005 and October 2005. K and mean size of hydraulically active pores were measured in situ at three water potentials (?0.6, ?0.2 and ?0.05 kPa) at the soil surface and at 10 cm depth. In November 2004 and May 2005, pore space was described using 2D image analysis of pores on undisturbed soil samples in the 0–10 cm layer and in the 10–20 cm layer. The major differences were caused by soil tillage that created two heterogeneous soil layers and increased K in the 0–10 cm layer relative to NT. The effects of cover crop on K and porosity were not affected by the root type: there were no major differences between the grass cover crop (fibrous‐root type) and the leguminous ones (tap‐root type). However, we recorded larger functional pores and more tubules in the no‐till treatments with a cover crop, compared with the no‐till treatment without cover crop; this was probably the result of root activity. Although these changes generally did not result in larger values of K, they participated in the maintenance of soil structure and K over time. 相似文献
939.
重组质粒pP18PH3上含有SINPV的部分蛋白激酶基因。SINPV部分的蛋白激酶氨基酸序列与HaN-PV、HzNPV、SpliNPV、AfNPV、AcNPV、LdNPV蛋白激酶的氨基酸序列的同源性分别为45%、89%、37%、44%、38%和37%,其上含有蛋白激酶特征序列IVHANDVKLENVL。 相似文献
940.
家蚕核型多角体病毒p35基因的核苷酸序列分析 总被引:3,自引:0,他引:3
对家蚕核型多角体病毒苏州株 (BmNPVsu)p35基因的序列分析表明 :BmNPVsup35编码序列为 897nt,编码 2 98aa。同源性分析表明 :BmNPVsup35与BmNPVT3、AcNPV、SlNPV在核苷酸水平上同源性分别为 99.5%、95.1 %、89.3% ,在氨基酸水平上的同源性分别为 98.7%、89.4 %、76.4 % ,显示了杆状病毒p35基因在进化上的保守性。BmNPVT3中位的N14 6、S2 0 2 、E2 0 4 、K2 4 4 ,在BmNPVsu中分别被G、N、Q、N取代 ,BmNPVT3中S2 2 2 ,在BmNPVsuP35中发生了缺失。推测BmNPVsuP35蛋白的功能及抑制细胞凋亡的能力与BmNPVT3P35蛋白的相似 相似文献