Gene innovation plays an essential role in trait evolution.Rhizobial symbioses,the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae,is one of the most attractive evolution event...Gene innovation plays an essential role in trait evolution.Rhizobial symbioses,the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae,is one of the most attractive evolution events.However,the gene innovations underlying Leguminosae root nodule symbiosis(RNS)remain largely unknown.Here,we investigated the gene gain event in Leguminosae RNS evolution through comprehensive phylogenomic analyses.We revealed that Leguminosae-gain genes were acquired by gene duplication and underwent a strong purifying selection.Kyoto Encyclopedia of Genes and Genomes analyses showed that the innovated genes were enriched in flavonoid biosynthesis pathways,particular downstream of chalcone synthase(CHS).Among them,Leguminosae-gain typeⅡchalcone isomerase(CHI)could be further divided into CHI1A and CHI1B clades,which resulted from the products of tandem duplication.Furthermore,the duplicated CHI genes exhibited exon–intron structural divergences evolved through exon/intron gain/loss and insertion/deletion.Knocking down CHI1B significantly reduced nodulation in Glycine max(soybean)and Medicago truncatula;whereas,knocking down its duplication gene CHI1A had no effect on nodulation.Therefore,Leguminosae-gain typeⅡCHI participated in RNS and the duplicated CHI1A and CHI1B genes exhibited RNS functional divergence.This study provides functional insights into Leguminosae-gain genetic innovation and sub-functionalization after gene duplication that contribute to the evolution and adaptation of RNS in Leguminosae.展开更多
在计算大规模介质-金属复合周期结构的电磁散射时,传统积分方程方法存在未知量大、存储占用多和计算时间长等问题。本文采用广义PMCHWT(Poggio-Miller-Chang-Harrington-Wu-Tsai)-电场积分方程(electric field integral equation,EFIE)...在计算大规模介质-金属复合周期结构的电磁散射时,传统积分方程方法存在未知量大、存储占用多和计算时间长等问题。本文采用广义PMCHWT(Poggio-Miller-Chang-Harrington-Wu-Tsai)-电场积分方程(electric field integral equation,EFIE)方法计算均匀介质-金属复合结构的电磁响应。该方法通过在分界面处设置区域连接模型(contact-region modeling,CRM)来保证边界处的连续性。为加速子阵列阻抗矩阵填充,采用快速偶极子方法(fast dipole method,FDM)来提高计算效率并降低内存占用。结合子全域(sub-entire-domain,SED)基函数方法,子阵列的电流分布特征可被推广到大规模介质-金属复合周期结构的电磁场计算中。数值算例表明,本文方法能够在保证计算精度的同时大幅度降低计算代价,内存占用降低至商业软件Altair FEKO(使用多层快速多极子方法)的1/10,计算误差在2.6 dB以内。展开更多
基金The National Natural Science Foundation of China(grant nos.32388201,32300512 and U22A20467)“Strategic Priority Research Program”of the Chinese Academy of Sciences(grant no.XDA24030501)+1 种基金CAS Project for Young Scientists in Basic Research(YSBR-078)the Xplorer Prize。
文摘Gene innovation plays an essential role in trait evolution.Rhizobial symbioses,the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae,is one of the most attractive evolution events.However,the gene innovations underlying Leguminosae root nodule symbiosis(RNS)remain largely unknown.Here,we investigated the gene gain event in Leguminosae RNS evolution through comprehensive phylogenomic analyses.We revealed that Leguminosae-gain genes were acquired by gene duplication and underwent a strong purifying selection.Kyoto Encyclopedia of Genes and Genomes analyses showed that the innovated genes were enriched in flavonoid biosynthesis pathways,particular downstream of chalcone synthase(CHS).Among them,Leguminosae-gain typeⅡchalcone isomerase(CHI)could be further divided into CHI1A and CHI1B clades,which resulted from the products of tandem duplication.Furthermore,the duplicated CHI genes exhibited exon–intron structural divergences evolved through exon/intron gain/loss and insertion/deletion.Knocking down CHI1B significantly reduced nodulation in Glycine max(soybean)and Medicago truncatula;whereas,knocking down its duplication gene CHI1A had no effect on nodulation.Therefore,Leguminosae-gain typeⅡCHI participated in RNS and the duplicated CHI1A and CHI1B genes exhibited RNS functional divergence.This study provides functional insights into Leguminosae-gain genetic innovation and sub-functionalization after gene duplication that contribute to the evolution and adaptation of RNS in Leguminosae.
文摘在计算大规模介质-金属复合周期结构的电磁散射时,传统积分方程方法存在未知量大、存储占用多和计算时间长等问题。本文采用广义PMCHWT(Poggio-Miller-Chang-Harrington-Wu-Tsai)-电场积分方程(electric field integral equation,EFIE)方法计算均匀介质-金属复合结构的电磁响应。该方法通过在分界面处设置区域连接模型(contact-region modeling,CRM)来保证边界处的连续性。为加速子阵列阻抗矩阵填充,采用快速偶极子方法(fast dipole method,FDM)来提高计算效率并降低内存占用。结合子全域(sub-entire-domain,SED)基函数方法,子阵列的电流分布特征可被推广到大规模介质-金属复合周期结构的电磁场计算中。数值算例表明,本文方法能够在保证计算精度的同时大幅度降低计算代价,内存占用降低至商业软件Altair FEKO(使用多层快速多极子方法)的1/10,计算误差在2.6 dB以内。
文摘目的探讨枸杞多糖对亚健康小鼠机体免疫功能及抗疲劳作用的影响及其作用机制。方法采用复合因素建立亚健康小鼠模型,随机分为模型组、枸杞多糖高剂量组(400 mg/kg体重)和低剂量组(200 mg/kg体重),另设对照组(未建模),经小鼠灌胃给药,每天1次,灌胃21 d,对照组和模型组给予等量蒸馏水。对建模小鼠进行行为学评价;检测各组小鼠的免疫功能(脾脏和胸腺指数、T和B淋巴细胞增殖能力及CD4+/CD8+值)和抗疲劳能力(游泳力竭时间、下丘脑5-羟色胺(5-hydroxytryptamine,5-HT)和多巴胺(Dopamine,DA)含量及海马区谷氨酸受体NR2A m RNA表达水平)。结果模型小鼠体重、自主活动次数、挣扎时间及游泳力竭时间明显低于对照组(P<0.05),避暗穿梭次数明显高于对照组(P<0.05)。模型组小鼠的胸腺、脾脏指数、B淋巴细胞增殖能力、CD4+/CD8+值、游泳力竭时间、下丘脑DA含量及海马区NR2Am RNA的表达均显著低于对照组(P<0.05),5-HT含量明显高于对照组(P<0.05);枸杞多糖高剂量组小鼠胸腺指数、脾脏指数、B淋巴细胞增殖能力、CD4+/CD8+值、游泳力竭时间、下丘脑DA含量及小鼠海马NR2A m RNA的表达均显著高于模型组(P<0.05),且5-HT含量明显低于模型组(P<0.05);各组间T细胞增殖能力无明显变化。结论成功建立亚健康小鼠模型,枸杞多糖可提高亚健康模型小鼠的免疫功能及抗疲劳作用,为枸杞多糖的临床应用提供了实验依据。
