用于SCAR检测的基因组DNA简易提取法

用一种简单的方法,无需接触有毒的有机试剂,无需离心,即可从小麦叶片中提取完整的基因组DNA,质量满足SCAR检测的要求,该方法可在短时间内制备大量样品,适于进行遗传连锁性分析时对F2分离群体的单株检测和分子标记辅助选择时筛选育种材料,操作简单,实用性强,值得推广。     

iPSCs来源的血细胞在血液系统疾病中的应用与发展

骨髓（BM）移植已在许多血液病中成功应用多年,主要依赖于成人BM和外周血（PB）中的造血干细胞（HSCs）。然而,合适配型HSCs的稀缺限制了其临床应用,难以满足更多有需要的患者。诱导多能干细胞（iPSCs）的出现,有望解决这一难题。iPSCs具有分化成所有血细胞的潜能,使得HSCs和其他血细胞在血液病中的广泛应用成为可能。然而,临床应用iPSCs治疗血液病仍障碍重重。本文主要回顾了iPSCs在血液病中的应用和发展以及面临的问题和挑战。     

毛竹林集约经营对土壤固碳细菌群落结构和多样性的影响

为揭示毛竹集约经营对土壤固碳细菌的影响,分别采集集约经营时间为0、10、15、20年和25年的毛竹林土壤(0—20 cm和20—40 cm)土壤,应用实时荧光定量PCR、T-RFLP以及cbbL基因文库方法,分析毛竹林长期集约经营过程中土壤固碳细菌丰度和群落结构多样性的变化,通过冗余分析(RDA)探讨影响土壤固碳细菌群落的主要环境因素。结果表明,长期的集约经营显著提高了毛竹林表层和亚表层土壤的养分含量,土壤pH值却明显降低。集约经营毛竹林土壤固碳微生物数量并未表现出与SOC的相关性,而与N素水平的变化显著相关。具体表现为:随着集约经营的进行表层cbbL基因丰度呈先上升(10年)后下降的规律,与氮素水平呈正相关(P0.05);亚表层土壤cbbL基因丰度则呈直线下降的趋势,与C∶N呈正相关(P0.05)。集约经营导致表层和亚表层土壤微生物群落结构改变,表层固碳细菌多样性指数下降。由系统发育分析可知,不可培养固碳细菌占56%比例,土壤中共同的优势种类多为变形菌和放线菌,以兼性自养为主。RDA分析结果表明土壤酸化和养分积累是毛竹林土壤固碳细菌群落和多样性变化的重要原因。     

RNA‐guided Cas9 as an in vivo desired‐target mutator in maize

The RNA‐guided Cas9 system is a versatile tool for genome editing. Here, we established a RNA‐guided endonuclease (RGEN) system as an in vivo desired‐target mutator (DTM) in maize to reduce the linkage drag during breeding procedure, using the LIGULELESS1 (LG1) locus as a proof‐of‐concept. Our system showed 51.5%–91.2% mutation frequency in T0 transgenic plants. We then crossed the T1 plants stably expressing DTM with six diverse recipient maize lines and found that 11.79%–28.71% of the plants tested were mutants induced by the DTM effect. Analysis of successive F2 plants indicated that the mutations induced by the DTM effect were largely heritable. Moreover, DTM‐generated hybrids had significantly smaller leaf angles that were reduced more than 50% when compared with that of the wild type. Planting experiments showed that DTM‐generated maize plants can be grown with significantly higher density and hence greater yield potential. Our work demonstrate that stably expressed RGEN could be implemented as an in vivoDTM to rapidly generate and spread desired mutations in maize through hybridization and subsequent backcrossing, and hence bypassing the linkage drag effect in convention introgression methodology. This proof‐of‐concept experiment can be a potentially much more efficient breeding strategy in crops employing the RNA‐guided Cas9 genome editing.     

‘圣诞快乐’朱顶红花芽分化研究

采用解剖观测和石蜡切片技术,对朱顶红品种‘圣诞快乐’花芽生长情况、花器官分化和性细胞分化过程进行了研究,以明确朱顶红花芽分化特征,为其花发育、花期调控、杂交育种和系统分类研究提供理论依据。结果表明：‘圣诞快乐’朱顶红每年产生2个花序芽,在第2年完成其内花芽花器官分化,经过低温作用后于第3年盛开,其中第2个花序偶有败育发生;花器官分化过程包括花原基分化期、外花被原基分化期、内花被原基分化期、雄蕊原基分化期、心皮原基分化期,对应的花芽大小分别约为0.02、0.05、0.1、0.2、0.3 cm,所有花器官均为螺旋状向心式发生;朱顶红花药4室,花药壁从外至内由表皮、药室内壁、中层和绒毡层组成,绒毡层类型为分泌型,小孢子减数分裂类型为连续型,四分体排列方式为十字交叉型,成熟花粉粒为2-细胞型;朱顶红雌蕊3心皮,下位子房,中轴胎座,3心室,每室两列倒生胚珠,胚珠为双珠被,厚珠心,具葱型胚囊。     

毛竹β-1,4-糖苷酶基因cDNA克隆与表达分析

根据水稻β-1,4-糖苷酶(korrigan)基因的保守区序列设计引物,以毛竹cDNA为模板,采用PCR方法,成功扩增出1个含有完整阅读框架的cDNA序列,长度为2191bp,共编码617个氨基酸,将其命名为PeKOR基因。其氨基酸序列分析的结果表明,PeKOR与其他β-1,4-糖苷酶有较高的同源性,同水稻序列相似性高达91%,且其序列具有典型的Glycosyl hydrolase9super family结构域,推测此PeKOR为毛竹β-1,4-糖苷酶基因。在竹笋中采用半定量方法研究该基因的表达情况,结果表明该基因在高温条件下表达量较低温条件下明显升高。     

动物体内的逆流倍增系统

介绍了逆流倍增的概念,详细阐述了在动物体的呼吸系统、循环系统、排泄系统中的逆流倍增系统。     

Tunable photoluminescence properties of Sr1‐yCayMoO4:Sm3+ phosphors (0 ≤ y < 1)

A series of Sr_1‐x‐yCa_yMoO₄:xSm³⁺ (0 ≤ x ≤ 7 mol% and 0 ≤ y < 1) phosphors was synthesized by a conventional solid‐state reaction method in air, and their structural and spectroscopic properties were investigated. The optimal doping concentration of Sm³⁺ in SrMoO₄:Sm³⁺ phosphor is 5 mol%. Under excitation with 275 nm, in Sr_1‐x‐yCa_yMoO₄:xSm³⁺ (0 ≤ x ≤ 7 mol% and 0 ≤ y < 1) phosphors, the emission band of the host was found to overlap with the excitation bands peaking at ~500 nm of Sm³⁺ ion, and the energy transfer from MoO₄^2? group to Sm³⁺ ion can also be observed. The International Commission on Illumination (CIE) chromaticity coordinates of Sr_0.95‐yCa_yMoO₄:0.05Sm³⁺ phosphors with excitation 275 nm varied systematically from an orange (0.4961, 0.3761) (y = 0) to a white color (0.33, 0.3442) (y = 0.95) with increasing calcium oxide (CaO) concentration. However, Sr_0.95‐yCa_yMoO₄:0.05Sm³⁺ phosphors with excitation at 404 nm only showed red emission and the energy transfer between MoO₄^2? group to Sm³⁺ ion was not observed. The complex mechanisms of luminescence and energy transfer are discussed by energy level diagrams of MoO₄^2? group and Sm³⁺ ion. Copyright © 2015 John Wiley & Sons, Ltd.