【目的】分析玉米脱镁叶绿酸氧化酶基因ZmPAO序列多态性,并挖掘该基因与玉米成熟后期穗位叶叶绿素组分含量相关的功能位点,为基于ZmPAO开发功能标记提供结构信息,有助于对玉米成熟后期叶绿素代谢遗传机制的理解。【方法】以141份具有广...【目的】分析玉米脱镁叶绿酸氧化酶基因ZmPAO序列多态性,并挖掘该基因与玉米成熟后期穗位叶叶绿素组分含量相关的功能位点,为基于ZmPAO开发功能标记提供结构信息,有助于对玉米成熟后期叶绿素代谢遗传机制的理解。【方法】以141份具有广泛遗传变异的玉米自交系为试验材料组成关联群体,以2个环境7个时间点的叶绿素组分含量为表型数据,利用Tassel 5.0通过混合线性模型(MLM,mixed linear model)开展玉米脱镁叶绿酸氧化酶基因(ZmPAO)与成熟后不同时期叶绿素组分变化的相关变异位点的关联分析,并对性状的有效关联位点进行单倍型分析。【结果】在玉米生长后期大部分取样时间点的叶绿素组分含量变异较大,叶绿素a普遍低于叶绿素b的含量,最终总叶绿素(叶绿素a与叶绿素b的和)有下降趋势。结果共鉴定ZmPAO中19个有效功能位点,其中4个处于外显子区,1个位于UTR区域,其他均位于内含子区域;功能位点对叶绿素组分含量变异的表型解释率在3.89%~16.57%,总表型效应在5.24%~41.78%。来自第6个内含子的位点S3235对于Yang-chlb6有高达16.57%的表型解释率;第7外显子S3675分别解释了Yang-chla1和Yangchlb1表型变异的12.16%和14.14%。性状显著单倍型中有利位点和关联分析的变异位点偏好相似。【结论】有效功能位点挖掘和性状单倍型分析表明,ZmPAO外显子发生了2个氨基酸变异,均由疏水氨基酸转化为亲水氨基酸,说明该基因可能通过蛋白结构的变异进行调控,但较多关联位点处于非编码区,说明该基因也受转录水平的调控。转录水平受环境影响较大,故导致该基因出现不同地点因播期和生育期的不同找到的关联位点并不一致,但有效变异位点的存在具有普遍性。展开更多
The water-soluble polysaccharides isolated from the leaves of Panax ginseng C. A. Meyer were totally fractionated into one neutral fraction（GLPN-1）, six acidic fractions（GLPN-2, GLPA-1a, GLPA-1b, GLPA-1c, GLPA-2 an...The water-soluble polysaccharides isolated from the leaves of Panax ginseng C. A. Meyer were totally fractionated into one neutral fraction（GLPN-1）, six acidic fractions（GLPN-2, GLPA-1a, GLPA-1b, GLPA-1c, GLPA-2 and GLPA-3） by a combination of ethanol precipitation, ion-exchange and gel permeation chromatography. All the fractions were analyzed by determining monosaccharide composition, molecular weight distribution. The resuits show that GLPN-1 was mainly composed of Gal（38.1%） and Ara（33.6%） and presumed to be an arabinogalactan. GLPA-1a, GLPA-1b and GLPA-2 mainly contained Gal, Ara, Rha and GalA. The amount of Gal and Ara acounted for over 50% of total sugar and the amount of Rha was more than 10%. The molar ratios of Rha/GalA in GLPA-1a, GLPA-1b and GLPA-2 were 1：1, 1：2 and 1：2.7, respectively, indicating that they belong to type-1 rhamnogalacturonan （RG-1）-rich pectin. GLPA-1c was mainly composed of GalA（78%）, belonging to homogalacturonan（HG）-rich pectin. GLPA-3 might be a glycoprotein.展开更多
文摘【目的】分析玉米脱镁叶绿酸氧化酶基因ZmPAO序列多态性,并挖掘该基因与玉米成熟后期穗位叶叶绿素组分含量相关的功能位点,为基于ZmPAO开发功能标记提供结构信息,有助于对玉米成熟后期叶绿素代谢遗传机制的理解。【方法】以141份具有广泛遗传变异的玉米自交系为试验材料组成关联群体,以2个环境7个时间点的叶绿素组分含量为表型数据,利用Tassel 5.0通过混合线性模型(MLM,mixed linear model)开展玉米脱镁叶绿酸氧化酶基因(ZmPAO)与成熟后不同时期叶绿素组分变化的相关变异位点的关联分析,并对性状的有效关联位点进行单倍型分析。【结果】在玉米生长后期大部分取样时间点的叶绿素组分含量变异较大,叶绿素a普遍低于叶绿素b的含量,最终总叶绿素(叶绿素a与叶绿素b的和)有下降趋势。结果共鉴定ZmPAO中19个有效功能位点,其中4个处于外显子区,1个位于UTR区域,其他均位于内含子区域;功能位点对叶绿素组分含量变异的表型解释率在3.89%~16.57%,总表型效应在5.24%~41.78%。来自第6个内含子的位点S3235对于Yang-chlb6有高达16.57%的表型解释率;第7外显子S3675分别解释了Yang-chla1和Yangchlb1表型变异的12.16%和14.14%。性状显著单倍型中有利位点和关联分析的变异位点偏好相似。【结论】有效功能位点挖掘和性状单倍型分析表明,ZmPAO外显子发生了2个氨基酸变异,均由疏水氨基酸转化为亲水氨基酸,说明该基因可能通过蛋白结构的变异进行调控,但较多关联位点处于非编码区,说明该基因也受转录水平的调控。转录水平受环境影响较大,故导致该基因出现不同地点因播期和生育期的不同找到的关联位点并不一致,但有效变异位点的存在具有普遍性。
基金Supported by the National Natural Science Foundation of China(Nos.30570417 and 30973857)the Natural Science Foundation of Jilin Province(No.20070710)the Natural Science Foundation of Changchun, China(Nos.2009081 and 09SF03)
文摘The water-soluble polysaccharides isolated from the leaves of Panax ginseng C. A. Meyer were totally fractionated into one neutral fraction（GLPN-1）, six acidic fractions（GLPN-2, GLPA-1a, GLPA-1b, GLPA-1c, GLPA-2 and GLPA-3） by a combination of ethanol precipitation, ion-exchange and gel permeation chromatography. All the fractions were analyzed by determining monosaccharide composition, molecular weight distribution. The resuits show that GLPN-1 was mainly composed of Gal（38.1%） and Ara（33.6%） and presumed to be an arabinogalactan. GLPA-1a, GLPA-1b and GLPA-2 mainly contained Gal, Ara, Rha and GalA. The amount of Gal and Ara acounted for over 50% of total sugar and the amount of Rha was more than 10%. The molar ratios of Rha/GalA in GLPA-1a, GLPA-1b and GLPA-2 were 1：1, 1：2 and 1：2.7, respectively, indicating that they belong to type-1 rhamnogalacturonan （RG-1）-rich pectin. GLPA-1c was mainly composed of GalA（78%）, belonging to homogalacturonan（HG）-rich pectin. GLPA-3 might be a glycoprotein.
