尖孢镰刀菌古巴专化型(Fusarium oxysporum f. sp. cubense,Foc)依据对寄主易感性分为4个不同的生理小种,其中4号生理小种(Foc4)几乎能危害目前所有栽培品种。为研究其SIX(secreted in xylem)蛋白编码基因SIX2和SIX6在Foc4对寄主差异性...尖孢镰刀菌古巴专化型(Fusarium oxysporum f. sp. cubense,Foc)依据对寄主易感性分为4个不同的生理小种,其中4号生理小种(Foc4)几乎能危害目前所有栽培品种。为研究其SIX(secreted in xylem)蛋白编码基因SIX2和SIX6在Foc4对寄主差异性选择中的作用,利用PEG介导的原生质体转化法将基于pCT74质粒框架构建的SIX2、SIX6基因敲除质粒分别转入Foc4 B2菌株,分别得到了SIX2和SIX6基因敲除突变体,然后分析敲除突变体与野生型的生物学特性差异。生物学研究结果表明:SIX2、SIX6基因的缺失突变体均呈现菌丝稀疏、生长速率减慢、产孢率降低、菌丝异核率增加,对渗透压、外源氧等外源胁迫更为敏感等特征。致病力分析实验发现ΔFoSIX2和ΔFoSIX6突变体的孢子在香蕉苗的幼嫩根部附着量减少,孢子根部定殖能力降低;ΔFoSIX2菌株基本上丧失了对巴西蕉的致病力,而对粉蕉仍有较强的致病能力;ΔFoSIX6菌株则对粉蕉苗、巴西香蕉苗盆栽致病力均呈极显著下降。依据生物学与致病力测定结果,推测Foc4中SIX6基因决定Foc4对寄主的致病力,而SIX2基因则决定Foc4对寄主的差异性选择能力。展开更多
BACKGROUND Juvenile-onset primary open-angle glaucoma(JOAG),characterized by severe elevation of intraocular pressure and optic neuropathy prior to the age of 40,is a rare subtype of primary open-angle glaucoma.Severa...BACKGROUND Juvenile-onset primary open-angle glaucoma(JOAG),characterized by severe elevation of intraocular pressure and optic neuropathy prior to the age of 40,is a rare subtype of primary open-angle glaucoma.Several genetic mutations have been associated with JOAG.CASE SUMMARY The proband patient was a young male,diagnosed with primary open-angle glaucoma at the age of 27.The patient and his unaffected parents who have been excluded from classic genetic mutations for primary open-angle glaucoma were included to explore for other possible genetic variants through whole genome sequencing and bioinformatics analysis.In this trio,we found two heterozygous variants inherited from the parents in the proband:c.281G>A,p.Arg94His in OLFM2 and c.177C>G,p.Ile59Met in SIX6.Both genetic mutations are predicted through bioinformatics analysis to replace evolutionary conserved amino acids,therefore rendering a pathogenic effect on proteins.In contrast,very low frequencies for these genetic mutations were recorded in most common control databases.CONCLUSION This is the first report on coinherited mutations of OLFM2 and SIX6 in a JOAG family,which shows the complexity of JOAG inheritance.Large-scale clinical screening and molecular functional investigations on these coinherited mutations are imperative to improve our understanding of the development of JOAG.展开更多
文摘尖孢镰刀菌古巴专化型(Fusarium oxysporum f. sp. cubense,Foc)依据对寄主易感性分为4个不同的生理小种,其中4号生理小种(Foc4)几乎能危害目前所有栽培品种。为研究其SIX(secreted in xylem)蛋白编码基因SIX2和SIX6在Foc4对寄主差异性选择中的作用,利用PEG介导的原生质体转化法将基于pCT74质粒框架构建的SIX2、SIX6基因敲除质粒分别转入Foc4 B2菌株,分别得到了SIX2和SIX6基因敲除突变体,然后分析敲除突变体与野生型的生物学特性差异。生物学研究结果表明:SIX2、SIX6基因的缺失突变体均呈现菌丝稀疏、生长速率减慢、产孢率降低、菌丝异核率增加,对渗透压、外源氧等外源胁迫更为敏感等特征。致病力分析实验发现ΔFoSIX2和ΔFoSIX6突变体的孢子在香蕉苗的幼嫩根部附着量减少,孢子根部定殖能力降低;ΔFoSIX2菌株基本上丧失了对巴西蕉的致病力,而对粉蕉仍有较强的致病能力;ΔFoSIX6菌株则对粉蕉苗、巴西香蕉苗盆栽致病力均呈极显著下降。依据生物学与致病力测定结果,推测Foc4中SIX6基因决定Foc4对寄主的致病力,而SIX2基因则决定Foc4对寄主的差异性选择能力。
基金the Guangzhou Science and Technology Plan Project,No.201803040020 and 201903010065the Guangdong Natural Science Foundation,No.2020A1515010168and the Research Funds of the State Key Laboratory of Ophthalmology,No.PT1001022.
文摘BACKGROUND Juvenile-onset primary open-angle glaucoma(JOAG),characterized by severe elevation of intraocular pressure and optic neuropathy prior to the age of 40,is a rare subtype of primary open-angle glaucoma.Several genetic mutations have been associated with JOAG.CASE SUMMARY The proband patient was a young male,diagnosed with primary open-angle glaucoma at the age of 27.The patient and his unaffected parents who have been excluded from classic genetic mutations for primary open-angle glaucoma were included to explore for other possible genetic variants through whole genome sequencing and bioinformatics analysis.In this trio,we found two heterozygous variants inherited from the parents in the proband:c.281G>A,p.Arg94His in OLFM2 and c.177C>G,p.Ile59Met in SIX6.Both genetic mutations are predicted through bioinformatics analysis to replace evolutionary conserved amino acids,therefore rendering a pathogenic effect on proteins.In contrast,very low frequencies for these genetic mutations were recorded in most common control databases.CONCLUSION This is the first report on coinherited mutations of OLFM2 and SIX6 in a JOAG family,which shows the complexity of JOAG inheritance.Large-scale clinical screening and molecular functional investigations on these coinherited mutations are imperative to improve our understanding of the development of JOAG.
