Growth monitoring indicated that the height of‘Kanshu’plants with‘Nantong-xiaofangshi’as an interstock was significantly shorter than that of‘Kanshu’plants with no interstock.A transcriptome analysis of the two ...Growth monitoring indicated that the height of‘Kanshu’plants with‘Nantong-xiaofangshi’as an interstock was significantly shorter than that of‘Kanshu’plants with no interstock.A transcriptome analysis of the two graft combinations(‘Kanshu’/Diospyros lotus and‘Kanshu’/‘Nantong-xiaofangshi’/Diospyros lotus)was conducted to explore the dwarfing genes related to the use of the‘Nantong-xiaofangshi’interstock.Hormone levels and water conductance were also measured in these two graft combinations.The results indicated that the levels of both IAA and GA were lower in‘Kanshu’that had been grafted onto the‘Nantong-xiaofangshi’interstock than in‘Kanshu’with no interstock;additionally,the water conductance was lower in grafts with interstocks than in grafts without interstocks.The expression of AUX/IAA and auxin-responsive GH3 genes was enhanced in scions grafted on the interstock and was negatively correlated with the IAA content and growth of scions.The expression of GA2ox,DELLA,and SPINDLY genes were also upregulated and associated with a decrease in the level of GA in scions grafted on the interstock.Since one of the GA2ox unigenes was annotated as DkGA2ox1 in Diospyros kaki,but was not functionally validated,a functional analysis was conducted in transgenic tobacco.Overexpression of DkGA2ox1 in transgenic plants resulted in a dwarf phenotype that could be recovered by the exogenous application of GA3.We conclude that the‘Nantong-xiaofangshi’interstock affects the water conductance and expression of genes related to the metabolism and transduction of IAA and GA in the grafted scion and thus regulates phytohormone levels,producing dwarfing.展开更多
HoneySweet’plum(Prunus domestica)is resistant to Plum pox potyvirus,through an RNAi-triggered mechanism.Determining the precise nature of the transgene insertion event has been complicated due to the hexaploid genome...HoneySweet’plum(Prunus domestica)is resistant to Plum pox potyvirus,through an RNAi-triggered mechanism.Determining the precise nature of the transgene insertion event has been complicated due to the hexaploid genome of plum.DNA blots previously indicated an unintended hairpin arrangement of the Plum pox potyvirus coat protein gene as well as a multicopy insertion event.To confirm the transgene arrangement of the insertion event,‘HoneySweet’DNA was subjected to whole genome sequencing using Illumina short-read technology.Results indicated two different insertion events,one containing seven partial copies flanked by putative plum DNA sequence and a second with the predicted inverted repeat of the coat protein gene driven by a double 35S promoter on each side,flanked by plum DNA.To determine the locations of the two transgene insertions,a phased plum genome assembly was developed from the commercial plum‘Improved French’.A subset of the scaffolds(2447)that were>10 kb in length and representing,>95%of the genome were annotated and used for alignment against the‘HoneySweet’transgene reads.Four of eight matching scaffolds spanned both insertion sites ranging from 157,704 to 654,883 bp apart,however we were unable to identify which scaffold(s)represented the actual location of the insertion sites due to potential sequence differences between the two plum cultivars.Regardless,there was no evidence of any gene(s)being interrupted as a result of the insertions.Furthermore,RNA-seq data verified that the insertions created no new transcriptional units and no dramatic expression changes of neighboring genes.展开更多
基金supported by the Science and Technology Special Project in North Jiangsu Research Funds(SZ-LYG2017004)the National Public Welfare Industry(Agriculture)Project Special Scientific Research Funds(201203047).
文摘Growth monitoring indicated that the height of‘Kanshu’plants with‘Nantong-xiaofangshi’as an interstock was significantly shorter than that of‘Kanshu’plants with no interstock.A transcriptome analysis of the two graft combinations(‘Kanshu’/Diospyros lotus and‘Kanshu’/‘Nantong-xiaofangshi’/Diospyros lotus)was conducted to explore the dwarfing genes related to the use of the‘Nantong-xiaofangshi’interstock.Hormone levels and water conductance were also measured in these two graft combinations.The results indicated that the levels of both IAA and GA were lower in‘Kanshu’that had been grafted onto the‘Nantong-xiaofangshi’interstock than in‘Kanshu’with no interstock;additionally,the water conductance was lower in grafts with interstocks than in grafts without interstocks.The expression of AUX/IAA and auxin-responsive GH3 genes was enhanced in scions grafted on the interstock and was negatively correlated with the IAA content and growth of scions.The expression of GA2ox,DELLA,and SPINDLY genes were also upregulated and associated with a decrease in the level of GA in scions grafted on the interstock.Since one of the GA2ox unigenes was annotated as DkGA2ox1 in Diospyros kaki,but was not functionally validated,a functional analysis was conducted in transgenic tobacco.Overexpression of DkGA2ox1 in transgenic plants resulted in a dwarf phenotype that could be recovered by the exogenous application of GA3.We conclude that the‘Nantong-xiaofangshi’interstock affects the water conductance and expression of genes related to the metabolism and transduction of IAA and GA in the grafted scion and thus regulates phytohormone levels,producing dwarfing.
文摘HoneySweet’plum(Prunus domestica)is resistant to Plum pox potyvirus,through an RNAi-triggered mechanism.Determining the precise nature of the transgene insertion event has been complicated due to the hexaploid genome of plum.DNA blots previously indicated an unintended hairpin arrangement of the Plum pox potyvirus coat protein gene as well as a multicopy insertion event.To confirm the transgene arrangement of the insertion event,‘HoneySweet’DNA was subjected to whole genome sequencing using Illumina short-read technology.Results indicated two different insertion events,one containing seven partial copies flanked by putative plum DNA sequence and a second with the predicted inverted repeat of the coat protein gene driven by a double 35S promoter on each side,flanked by plum DNA.To determine the locations of the two transgene insertions,a phased plum genome assembly was developed from the commercial plum‘Improved French’.A subset of the scaffolds(2447)that were>10 kb in length and representing,>95%of the genome were annotated and used for alignment against the‘HoneySweet’transgene reads.Four of eight matching scaffolds spanned both insertion sites ranging from 157,704 to 654,883 bp apart,however we were unable to identify which scaffold(s)represented the actual location of the insertion sites due to potential sequence differences between the two plum cultivars.Regardless,there was no evidence of any gene(s)being interrupted as a result of the insertions.Furthermore,RNA-seq data verified that the insertions created no new transcriptional units and no dramatic expression changes of neighboring genes.