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901.
ABSTRACT1. Osteopontin (OPN) is a highly phosphorylated acidic glycoprotein that plays a crucial role in eggshell formation. In this study, an 893-bp cDNA sequence of the OPN gene, which encodes 180 amino acids, was obtained.2. Polymorphisms of the OPN gene were analysed with DNA sequencing and polymerase chain reaction-single-strand conformation polymorphism methods in two Chinese domestic laying ducks (Jingding n = 100, Youxian n = 478, respectively).3. One polymorphism was identified in exon 7 (NM_ 004676534.1:c.267T>C) of the OPN gene, with three genotypes: TT (both T allels weren’t mutated (wild type)), TC (one T allel was mutated to C (heterozygote genotype)) and CC. (both T allels were mutated to C (homozygote 20 genotype)) Association analysis with egg quality traits in the two Chinese domestic laying ducks showed that the ducks with the CC genotype had significantly greater eggshell strength and eggshell thickness (p < 0.05). Hence, the exon 7 267T>C polymorphism of the OPN gene is a potentially valuable genetic marker for laying duck breeding programmes. 相似文献
902.
903.
文章对2006-2010年《内蒙古农业科技》进行了载文量与相关数据的对比分析、栏目载文量分析、期刊应用分析、高引文献分析、高引文献作者分布分析,并对学报的发展提出了建议。 相似文献
904.
905.
To provide genetic information and materials for breeding hybrid japonica rice with wide adaptability and strong competitive advantage of yield,elite alleles and their carrier varieties of growth duration (GD) and productive panicle number per plant (PN) were detected.A natural population composed of 94 japonica varieties was phenotyped for the GD,PN and plant height (PH) in two environments.The conditional phenotypic data were transferred by the linear model method in software QGAStation 1.0,and association mapping based on the unconditional and conditional phenotype values of GD and PN was analyzed by using general linear model in software TASSEL.A total of 34 simple sequence repeat (SSR) marker loci associated with GD and PN were detected in the two environments.Among them,15 were associated with GD,and 19 were associated with PN.Four elite alleles of RM8095-120bp,RM7102-176bp,RM72-170bp and RM72-178bp were associated with GD,and their carrier varieties were Hongmangshajing,Nipponbare,Hongmangshajing and Nannongjing 62401,respectively.These elite alleles from the carrier varieties can shorten GD by 2.03 9.93 d when they were introduced into improved materials.RM72-182bp associated with PN was an elite allele,and its carrier variety was Xiaoqingzhong.It can increase PN by three when introduced into improved materials.Moreover,these elite alleles can be used to improve target traits without influencing another two traits. 相似文献
906.
Shou-qin GU Yang YANG Po LI Chang-zhi ZHANG Yu FAN Xiao-yu ZHANG Lan TIAN Zhi-min HAO Zhi-yan CAO Xiao-dong GONG Yong-shan FAN Jian-min HAN Jin-gao DONG 《农业科学学报》2013,12(12):2209-2216
Setosphaeria turcica, an essential phytopathogenic fungus, is the primary cause of serious yield losses in corn; however, its pathogenic mechanism is poorly understood. We cloned STK2, a newly discovered mitogen-activated protein kinase gene with a deduced amino acid sequence that is 96% identical to MAK2 from Phaeosphaeria nodorum, 56% identical to KSS1 and 57% identical to FUS3 from Saccharomyces cerevisiae. To deduce Stk2 function in S. turcica and to identify the genetic relationship between STK2 and KSS1/FUS3 from S. cerevisiae, a restructured vector containing the open reading frame of STK2 was transformed into a fus3/kss1 double deletion mutant of S. cerevisiae. The results show that the STK2 complementary strain clearly formed pseudohyphae and ascospores, and the strain grew on the surface of the medium after rinsing with sterile water and the characteristics of the complementary strain was the same as the wild-type strain. Moreover, STK2 complemented the function of KSS1 in filamentation and invasive growth, as well as the mating behavior of FUS3 in S. cerevisiae, however, its exact functions in S. turcica will be studied in the future research. 相似文献
907.
为了获得纯化的SnRK1.1与FD蛋白,分析蛋白激酶SnRK1.1是否能够磷酸化开花调控途径中的转录因子FD,成功克隆了1 608 bp的SnRK1.1基因以及858 bp的FD与FD-T282A基因,分别与PGEX-4T-3载体连接,获得原核表达载体GST-SnRK1.1、GST-FD和GST-FD-T282A,并分别转化大肠杆菌BL21菌株;SDS-PAGE电泳和考马斯亮蓝染色(CBB)表明,0.5 mmol/L IPTG能够成功诱导出GST-SnRK1.1、GST-FD和GST-FD-T282A蛋白。利用GST纯化介质纯化获得了84 k Da的GST-SnRK1.1蛋白以及58 k Da的GST-FD与GST-FD-T282A融合蛋白;利用体外磷酸化体系证实SnRK1.1能够磷酸化FD,不能磷酸化突变的FD-T282A。研究结果为进一步解析SnRK1.1通过磷酸化转录因子FD参与开花途径调控的机制奠定了良好的基础。 相似文献
908.
909.
910.
Acute mountain sickness (AMS) is the greatest challenge of military medicine and wilderness medicine, as the increasing populations of entering Tibet and others who rapidly ascend to high altitude. AMS is considered as a kind of vascular dysfunction and disequilibrium of body fluid diseases induced by environmental stress. Studies reveal that endogenous nitric oxide (NO), a predominant endogenous vessel dilator, plays a crucial role in the pathogenesis of AMS. The decreased production and blocked delivery of NO cause dysfunction of the vascular system in hypoxic situations. Subsequently, AMS develops under the facilitations of alterations in brain and pulmonary blood vessels. NO or L-arginine (the precursor of NO) can also be used to prevent and treat AMS. This review will summarize the progress on the roles of NO in the pathogenesis, pathophysiology, treatment and prophylaxis of AMS. 相似文献