Resequencing core accessions of a pedigree identifies derivation of genomic segments and key agronomic trait loci during cotton improvement

Upland cotton (Gossypium hirsutum) is the world's largest source of natural fibre and dominates the global textile industry. Hybrid cotton varieties exhibit strong heterosis that confers high fibre yields, yet the genome‐wide effects of artificial selection that have influenced Upland cotton during its breeding history are poorly understood. Here, we resequenced Upland cotton genomes and constructed a variation map of an intact breeding pedigree comprising seven elite and 19 backbone parents. Compared to wild accessions, the 26 pedigree accessions underwent strong artificial selection during domestication that has resulted in reduced genetic diversity but stronger linkage disequilibrium and higher extents of selective sweeps. In contrast to the backbone parents, the elite parents have acquired significantly improved agronomic traits, with an especially pronounced increase in the lint percentage. Notably, identify by descent (IBD) tracking revealed that the elite parents inherited abundant beneficial trait segments and loci from the backbone parents and our combined analyses led to the identification of a core genomic segment which was inherited in the elite lines from the parents Zhong 7263 and Ejing 1 and that was strongly associated with lint percentage. Additionally, SNP correlation analysis of this core segment showed that a non‐synonymous SNP (A‐to‐G) site in a gene encoding the cell wall‐associated receptor‐like kinase 3 (GhWAKL3) protein was highly correlated with increased lint percentage. Our results substantially increase the valuable genomics resources available for future genetic and functional genomics studies of cotton and reveal insights that will facilitate yield increases in the molecular breeding of cotton.     

Efficient and green aqueous−solid system for transphosphatidylation to produce phosphatidylhydroxybutyrate: Potential drugs for central nervous system's diseases

The synthesis of nonnatural phospholipid, phosphatidylhydroxybutyrate (PB), was firstly introduced by phospholipase D (PLD)-mediated transphosphatidylation of phosphatidylcholine (PC) with sodium γ-hydroxybutyrate (NaGHB) in the aqueous–solid system. Nanoscale silicon dioxide (NSD) was employed as a carrier to provide an “artificial interphase” between PC and PLD. Special attention has been paid to the effect of the PC coverage on the surface area of hybrids of NSD-PC, the PC loading and the yield of PB. Results indicated that the highest PC loading of 98.3% and the highest PB yield of 97.3% were achieved. In addition, the free PLD in the aqueous–solid system showed the greater stability and pH tolerance than that in the traditional liquid–liquid system. The operational stability of free PLD solution was investigated. The yield of PB remained 70.7% after being used for five batches. The authors provide a new idea for drug design and the potential source of PB for medical experiments. PB is a potential drug and may have the excellent performance in the treatment of central nervous system's diseases. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2726, 2019     

大鼠尿激酶SYBR Green I real time RT-PCR引物的设计

设计用于SYBR Green I法实时定量逆转录多聚酶链反应(QRT-PCR)检测大鼠尿激酶型纤溶酶原激活因子(uPA)mRNA的引物。从基因库获取靶基因及相关序列,充分收集争分析相关生物信息学数据,应用Oligo 6.22设计出一对长度为21bp的引物,其GG含量为52.4%;上下游引物3’最稳定二聚体和及发夹结构的能量分别为-1.5、-0.40 kcal/mol和-3.5、-O.90 kcal/mol,引物间最稳定二聚体为-3.1 kcal/mol。5’端和中间△G值较高,高于3’端△G;引发效率分别455和403。实验证明,该引物能够高效、特异地实现对靶序列的检测,适用于SYBR Green I法实时定量检测(uPA)mRNA。     

沙井地区384例支原体药敏试验结果及分析

目的:了解本地区社区感染支原体的药物敏感情况。方法:对门诊标本培养出的384例支原体进行药敏试验(微量肉汤法)。结果:Uu对交沙霉素、克拉霉素及罗红霉素敏感性高,敏感率分别为98%、94%及93%;对环丙沙星、大观霉素耐药性高,敏感率分别为8%及11%。Mh对交沙霉素敏感率为89%、对大现霉素、多西环素、美满霉素的敏感率均为78%;对罗红霉素、红霉素耐药性高,敏感率分别为0%及11%。Uu合并Mh对交沙霉素、多西环素、美满霉素敏感性高,敏感率分别为85%、73%及69%,对红霉素、克拉霉素、大观霉素的敏感性均为0%,对罗红霉素、阿奇霉素、环丙沙星的敏感率均为4%。结论:支原体的敏感性存在时空差异,且不同类型的支原体对抗菌素的敏感性是不同的,应采用实验室结果而非经验指导用药。     

红谷霉素对细菌抑制效果研究

红谷霉素是链霉菌702发酵后所产的一种生物活性物质,具有较强抗细菌活性。研究表明,红谷霉素对大肠杆菌的最低抑菌浓度为40mg/L,对枯草芽胞杆菌的最低抑菌浓度为0.08mg/L。红谷霉素在微生物生长迟滞期添加比在其它生长阶段添加抑菌效果更好,红谷霉素对热和紫外比较稳定。通过与其他防腐剂的抑菌效果比较表明,红谷霉素对细菌的抑菌效果优于比较的防腐剂。     

原、异位保存东乡野生稻主要农艺性状的比较研究

为了解原、异位保存东乡野生稻主要农艺性状的变化,对庵家山普通野生稻原、异位群体进行了考察和比较分析。结果表明,原、异位保存的东乡野生稻在每穗总粒数、每穗实粒数、结实率等方面存在较大的差异,如异位保存的东乡野生稻每穗总粒数平均为58.28粒,比原位多11.44粒,但其每穗实粒数却较少,为9.89粒,结实率降低了45.43%。从种植环境可以发现,异位保存圃的环境不适宜东乡野生稻的生长,应该选择与原生境相类似的种植环境,以便于东乡野生稻的保存、研究与利用。     

首云铁矿废弃土壤对2种景天属植物生长的影响

为评价景天属（Sedum）植物在矿山废弃地植被恢复中的应用潜力,以2种景天：德国景天（S. hybridum ‘Immergrunchen’）和胭脂红景天（S. spurium ‘Coccineum’）的扦插苗为试验材料,通过盆栽试验研究其在北京首云铁矿废弃土壤（包括采矿区土壤、排土场土壤、尾矿砂）2个生长季内的各项生长指标,以确定其在各废弃土壤上的适应性,并运用相关分析和典范对应分析,探讨影响2种景天生长的主要土壤理化性质。结果表明：①2种景天在采矿区土壤、排土场土壤和尾矿砂上的存活率分别为40%~66%、68%~90%、33%~46%;②不同废弃土壤对2种景天的地上部分和地下根系的各项生长指标均产生了显著的抑制作用,但德国景天在采矿区土壤的适应性较好,可作为采矿区修复的推荐品种,胭脂红景天在排土场土壤的生长表现较好,可作为排土场的修复品种;③影响景天属植物生长的土壤因子为通气孔隙度和土壤含水量,其中通气孔隙度的解释率为12.4%,土壤含水量的解释率为8.6%。     

腊尔山区苗族学生头面部形态特征

本项目对1896例腊尔山区6~16岁苗族学生（男919例,女977例）进行了人体测量,测量了10项头面部形态指标,并根据公式计算13项头面部指数值。结果表明,苗族学生头面部各指标均值随年龄增长而增加,同年龄段头面部各指标均值男生一般高于女生,且多数年龄段差异有统计学意义;男性的头长宽的、形态面的、形态上面的、容貌面的、颧额宽的、容貌上面的和容貌上面高的指数以及女性的形态面的、形态上面的、容貌面的、颧下颌宽度的、容貌上面高的指数随年龄增长总体趋势是先增加后递减;男性头面高的以及女性的头长高的、头宽高的和头面宽的指数随年龄增长逐渐增加;男女性之间的头长高的、头宽高的和额顶宽的指数比较显示,多数年龄段差异有统计学意义;苗族学生头型以中头型、高头型、阔头型多见,面型以阔面型、阔上面型为主;相对于其他族群,腊尔山苗族男生面型短而宽,头型偏长,女生面型偏短,头型稍偏长而窄。腊尔山苗族学生头面部特征与融水苗族、土家族等族群较为接近,与哈萨克族、新乡汉族相距较远。