A subtractive cDNA library was developed to study genes associated with bud dormancy release in tree peonies. In order to identify genes that are highly expressed in buds released from dormancy, 588 clones were examin...A subtractive cDNA library was developed to study genes associated with bud dormancy release in tree peonies. In order to identify genes that are highly expressed in buds released from dormancy, 588 clones were examined by differential screening. Of these, 185 clones were selected to be sequenced. A total of 37 unique sequences were obtained of which only 31 sequences have matches in the NCBI database or the Arabidopsis thaliana protein database. Semi-quantitative RT-PCR was used to confirm further the expression profiles for 12 transcripts identified within the subtractive cDNA library. Gene ontology analyses indicated that many of the different genes identified have unknown or hypothetical functions while it is speculated that other genes play different mo- lecular roles. In our study, genes involved in bud dormancy release were growth-related or stress-responsive, while low-temperature-induced ribosomal proteins may also play a role in bud dormancy release. Our results provide interesting information for further understanding of the molecular mechanism of bud dormancy release in tree peonies.展开更多
Tree peonies native to China are a precious crop with ornamental,medicinal and edible oil properties,of which flare tree peony(Paeonia rockii)is one of the most significant germplasms in Paeonia.The development and ap...Tree peonies native to China are a precious crop with ornamental,medicinal and edible oil properties,of which flare tree peony(Paeonia rockii)is one of the most significant germplasms in Paeonia.The development and application of expressed sequence tag-simple sequence repeat(EST-SSR)markers are very valuable for genetic and breeding applications,but EST-SSR resources for the genus Paeonia are still limited.In this study,we first reported the development of SSRs within transcription factors(TFs)in P.rockii based on next-generation sequencing(NGS)and single-molecule long-read sequencing(SMLRS).A total of 166 EST-SSRs containing six nucleotide repeat types were identified from 959 candidate TFs associated with yield,with an average of one SSR per 5.83 unigenes.In total,102(61.45%)pairs of primers produced amplification products in the two RNA-seq cultivars.Among them,58(56.86%)pairs of primers from 18 gene families(AP2,b HLH,HSF,etc.)were identified to be polymorphic both in the parents of a linkage mapping population and in eight randomly selected accessions of P.rockii.Further,the 58 EST-SSRs indicated a high level of informativeness with PIC values ranging from 0.32 to 0.91(mean 0.70)after assessment in 37 tree peony accessions.Transferability studies indicated that the amplification ratio of the 58 pairs of primers ranged from 89.66 to 100%across seven species of Paeonia.In addition,a genetic relationship study was performed in 62 accessions.Cluster analysis using the neighbour-joining(NJ)tree demonstrated that major clusters corresponded to the known pedigree trees.Taken together,these newly developed EST-SSRs have a potential use in the conservation of tree peony germplasm and marker-assisted selection(MAS)breeding.展开更多
Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles ...Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles and techniques of plant propagation and improvement. Microstructures and fluctuations of phytohormones in the adventitious rooting were studied with the etiolated soft- wood shoots of Paeonia suffkuticosa ＇Yinfen Jinlin＇. There are no pre-primordia in the shoots of the cultivar. Adventitious roots are produced in five stages： shoot selection, primordium initiation, primordium growth, conducting tissue differentiation and root protru- sion. Primordia initiated in the cortex. The contents of the endogenous hormones, IAA, ABA and GA, were 5.842, 0.873 and 1.043 nmol·g^-1 FW on the bases of shoots, respectively. CTKs which included isopentenyl adenine （iPA）, zeatin riboside （ZR） and dihy- drozeatin riboside （DHZR） were 0.949, 0.695 and 2.034 nmol·g^-1 FW, respectively. DHZR is active among CTKs. The ratio of IAA to GA, CTK and ABA clearly increased at the stage of primordium initiation, while they showed low levels at the stages of primor- dium growth. The ratios were restored at the shoot levels at the stage of root protrusion. IBA provoked primordia initiation in the cortex, the vascular cambium, the pith and even in the callus induced on the base of shoots. ]AA levels in the treated shoots increased gradually to its highest level （three times of control） at the stage of conducting tissue differentiation. The ratios of IAA to GA, CTK and ABA clearly decreased at the stage of primordium initiation. The ratio of IAA to ABA is regulated at 10：1.展开更多
基金supported by the Natural Science Foundation of Shangdong Province,China(Z2005D04).
文摘A subtractive cDNA library was developed to study genes associated with bud dormancy release in tree peonies. In order to identify genes that are highly expressed in buds released from dormancy, 588 clones were examined by differential screening. Of these, 185 clones were selected to be sequenced. A total of 37 unique sequences were obtained of which only 31 sequences have matches in the NCBI database or the Arabidopsis thaliana protein database. Semi-quantitative RT-PCR was used to confirm further the expression profiles for 12 transcripts identified within the subtractive cDNA library. Gene ontology analyses indicated that many of the different genes identified have unknown or hypothetical functions while it is speculated that other genes play different mo- lecular roles. In our study, genes involved in bud dormancy release were growth-related or stress-responsive, while low-temperature-induced ribosomal proteins may also play a role in bud dormancy release. Our results provide interesting information for further understanding of the molecular mechanism of bud dormancy release in tree peonies.
基金supported by the National Key Research and Development Project(2019YFD1001500)the National Natural Science Foundation of China(31471898)。
文摘Tree peonies native to China are a precious crop with ornamental,medicinal and edible oil properties,of which flare tree peony(Paeonia rockii)is one of the most significant germplasms in Paeonia.The development and application of expressed sequence tag-simple sequence repeat(EST-SSR)markers are very valuable for genetic and breeding applications,but EST-SSR resources for the genus Paeonia are still limited.In this study,we first reported the development of SSRs within transcription factors(TFs)in P.rockii based on next-generation sequencing(NGS)and single-molecule long-read sequencing(SMLRS).A total of 166 EST-SSRs containing six nucleotide repeat types were identified from 959 candidate TFs associated with yield,with an average of one SSR per 5.83 unigenes.In total,102(61.45%)pairs of primers produced amplification products in the two RNA-seq cultivars.Among them,58(56.86%)pairs of primers from 18 gene families(AP2,b HLH,HSF,etc.)were identified to be polymorphic both in the parents of a linkage mapping population and in eight randomly selected accessions of P.rockii.Further,the 58 EST-SSRs indicated a high level of informativeness with PIC values ranging from 0.32 to 0.91(mean 0.70)after assessment in 37 tree peony accessions.Transferability studies indicated that the amplification ratio of the 58 pairs of primers ranged from 89.66 to 100%across seven species of Paeonia.In addition,a genetic relationship study was performed in 62 accessions.Cluster analysis using the neighbour-joining(NJ)tree demonstrated that major clusters corresponded to the known pedigree trees.Taken together,these newly developed EST-SSRs have a potential use in the conservation of tree peony germplasm and marker-assisted selection(MAS)breeding.
文摘Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles and techniques of plant propagation and improvement. Microstructures and fluctuations of phytohormones in the adventitious rooting were studied with the etiolated soft- wood shoots of Paeonia suffkuticosa ＇Yinfen Jinlin＇. There are no pre-primordia in the shoots of the cultivar. Adventitious roots are produced in five stages： shoot selection, primordium initiation, primordium growth, conducting tissue differentiation and root protru- sion. Primordia initiated in the cortex. The contents of the endogenous hormones, IAA, ABA and GA, were 5.842, 0.873 and 1.043 nmol·g^-1 FW on the bases of shoots, respectively. CTKs which included isopentenyl adenine （iPA）, zeatin riboside （ZR） and dihy- drozeatin riboside （DHZR） were 0.949, 0.695 and 2.034 nmol·g^-1 FW, respectively. DHZR is active among CTKs. The ratio of IAA to GA, CTK and ABA clearly increased at the stage of primordium initiation, while they showed low levels at the stages of primor- dium growth. The ratios were restored at the shoot levels at the stage of root protrusion. IBA provoked primordia initiation in the cortex, the vascular cambium, the pith and even in the callus induced on the base of shoots. ]AA levels in the treated shoots increased gradually to its highest level （three times of control） at the stage of conducting tissue differentiation. The ratios of IAA to GA, CTK and ABA clearly decreased at the stage of primordium initiation. The ratio of IAA to ABA is regulated at 10：1.
