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691.
中国荷斯坦牛CVM的基因检测及其与产奶性状的关联分析 总被引:1,自引:0,他引:1
脊椎畸形综合征(Complex vertebral malformation, CVM)是由位于牛第3号染色体(BTA3)的SLC35A3基因外显子4的一个单碱基突变(G559T)所致。该致病基因在世界许多国家的荷斯坦牛群中都有一定的比例。文章对北京地区38头优秀种公牛进行分析, 发现了4头携带者, 进而检测了这些携带者公牛的555头女儿的基因型, 其中携带者占检测母牛数的44.0%。此外, 关联分析结果表明, 携带者母牛与非携带者母牛的生产性能之间存在显著差异(P<0.01)。携带者母牛的5个产奶性状育种值均显著高于非携带者, 泌乳持续力和体细胞评分SCS的育种值也比非携带者略高。CVM致病基因可能与BTA3上影响产奶性状的QTL或基因连锁。因此, 建议生产中对CVM携带者进行逐步淘汰 相似文献
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-Galactosidase II2 (MW 43 390) from resting Vicia faba L. seeds had been shown to possess d-glucose/d-mannose-specific lectin activity. Inhibition studies with monosaccharides and an examination of the effects of heat and pH on the catalytic and lectin activities of the enzyme indicate that the enzyme substrate and the lectin haptens bind at different sites on the protein. d-Mannosebinding has been investigated by equilibrium dialysis and spectrophotometrically. Both methods yield Ka values of approx. 3·103 M-1 for the interaction and there would appear to be two mannosebinding sites per molecule of enzyme protein. The lectin properties of V. faba -galactosidase II2 have been discussed in relation to both V. faba lectin (favin) and other legume -galactosidases.Abbreviations con A
concanavalin A
- CM-cellulose
carboxymethyl cellulose
- MW
molecular weight
- PNPG
p-nitrophenyl -d-galactoside
- SDS
sodium dodecyl sulphate
- PAGE
polyacrylamide-gel electrophoresis 相似文献
694.
为测定牛卵巢丝氨酸蛋白酶35 (PRSS35)的CDS序列并进行生物信息学分析。试验根据NCBI上已公布牛PRSS35基因的mRNA序列设计特异性引物,使用RT-PCR技术扩增牛卵泡中PRSS35的CDS序列。结果显示,牛PRSS35基因CDS区序列全长为1 239 bp,共编码412个氨基酸,PRSS35与其他10个物种的同源序列相似性较高,且该蛋白具有一个长度为20个氨基酸的信号肽,具有11个O-糖基化位点和2个N-糖基化位点,以及3个磷酸化位点,并发现有一个典型的Tryp_Spc结构域,即胰蛋白酶样丝氨酸蛋白酶结构域。为进一步研究该基因及其编码蛋白在卵泡发育过程中所起的作用提供了一定的理论依据。 相似文献
695.
Georgios L. Georgalis 《Comptes Rendus Palevol》2019,18(7):801-815
I here describe new fossil remains of lizards and snakes from the late Miocene of Pikermi, near Athens, Greece. This classical locality, known since at least the middle of the 19th century, has yielded over the decades abundant mammal fossils, whereas squamate remains have been confined to early discoveries of Varanus remains during the 19th century. The first specimen among these varanid fossils, a large vertebra described by Albert Gaudry during the 1860s, represents also one of the earliest discoveries of a fossil monitor lizard worldwide. Nevertheless, this historically important specimen has only been briefly described and its so far only available images were the original lithographs and subsequent sketches of two only of its views. I here describe this specimen in detail and provide photographs of all its standard views. The additional squamate remains from the Pikermi area are fragmentary. Nevertheless, they document the presence in Pikermi of other lizard groups, such as lacertids and probable anguines, while snakes are described for the first time. Among the snake fossils, probable erycines and colubrids are identified; if indeed an erycine, this would be the oldest occurrence of that group in the Eastern Mediterranean, thus extending back its stratigraphic range in the area by several million years. 相似文献
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699.
用苜蓿银纹夜蛾核型多角体病毒( Ac N P V) 凋亡抑制基因p35 的合成引物,从棉铃虫核型多角体病毒( Ha N P V) 基因组中用 P C R 扩增到了1kb 片段。采用 P C R- 双脱氧核苷酸链终止银染法,测定了所扩增到的1 010bp 全序列,发现其开放阅读框完整,长897bp ,编码299 个氨基酸。用 D N A S I S 和 P R O S I S 软件分析发现,此片段与 Ac M N P V p35 基因同源区核苷酸同源性为91 % ,氨基酸同源性也达81 % ,证明了所扩增的片段是 Ha N P V 的p35 基因。为了研究此p35 基因的功能及其效应机制,克隆了这一基因并在大肠杆菌细胞中实现了表达。 相似文献
700.
Baculovirus has many advantages as vectors for gene transfer. We demonstrated that recombinant baculovirus vectors expressing
p35 (Ac-CMV-p35) and eGFP (Ac-CMV-GFP) could be transduced into human kidney 293 cells efficiently. The level of transgene expression
was viral dose dependent and high-level expression of the target gene could be achieved under the heterogonous promoter. MTT
assay suggested that both Ac-CMV-p35 and Ac-CMV-GFP did not have cytotoxic effect on human embryo kidney 293 cells. Cell growth
curve showed the Ac-CMV-p35 and Ac-CMV-GFP transduced and non-transduced cells had similar proliferation rate, so baculovirus-mediated
p35 expression had no adverse effect on cell proliferation. In addition, baculovirus-mediated p35 gene expression protected human embryo kidney 293 cells against apoptosis induced by various apoptosis inducers such as Actinomycin
D, UV or serum-free media. These results suggested that the baculovirus vector mediated p35 gene expression was functional and it could be widely used in molecular research and even gene therapy.
Foundation items: National Nature Science Foundations of China (30325002, 30670077) and Innovative Foundations Wuhan Institute
of Virology, CAS (020208) 相似文献