Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lili...Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lilies.Gibberellin(GA)is a large class of hormones and plays an important role in plant vegetative growth and reproductive development.GAMYB is a group of the R2R3-MYB family upregulated by gibberellin,and plays an important role in anther development.Here,we isolated a novel GAMYB,named LoMYB65,from lily,which was closely related to the AtMYB65 and AtMYB33 in Arabidopsis.Fluorescence quantitative PCR results showed that LoMYB65 was mainly expressed in lily anthers.LoMYB65 could be activated by 288μmol·L^(-1)GA3treatment and the LoMYB65 protein was located in the nucleus and cytoplasm,and had transactivation in yeast and tobacco leaf cells.The conserved motif within 226 amino acids of the C-terminal of LoMYB65 contributed to its transactivation.Overexpression of LoMYB65 caused dwarf phenotype,unnormal tapetum development,less seeds of siliques in transgenic Arabidopsis plants,the transgenic plants showed partly male sterile.Simultaneously,silencing of LoMYB65 with VIGS(Virus Induced Gene Silencing)in lily anthers caused unnormal pollen development and reduced the pollen amount.Overexpression of LoMYB65 in Arabidopsis and silencing of LoMYB65 in lily resulted in decreased pollen counts,so we speculate that LoMYB65 may be dose-dependent.Overall,these findings suggest that LoMYB65 may play an important role in anther development and pollen formation in lily.LoMYB65 may provide a useful candidate gene for pollenless breeding of lily.展开更多
Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellul...Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch.展开更多
基金supported by the National Key Research and Development Program of China(2022YFD1200500)the Fundamental Research Funds for the Central Universities(KYZZ2022004)+1 种基金the Project for Crop Germplasm Resources Conservation of Jiangsu(2021-SJ-011)the High Level Talent Project of the Top Six Talents in Jiangsu(NY-077)。
文摘Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lilies.Gibberellin(GA)is a large class of hormones and plays an important role in plant vegetative growth and reproductive development.GAMYB is a group of the R2R3-MYB family upregulated by gibberellin,and plays an important role in anther development.Here,we isolated a novel GAMYB,named LoMYB65,from lily,which was closely related to the AtMYB65 and AtMYB33 in Arabidopsis.Fluorescence quantitative PCR results showed that LoMYB65 was mainly expressed in lily anthers.LoMYB65 could be activated by 288μmol·L^(-1)GA3treatment and the LoMYB65 protein was located in the nucleus and cytoplasm,and had transactivation in yeast and tobacco leaf cells.The conserved motif within 226 amino acids of the C-terminal of LoMYB65 contributed to its transactivation.Overexpression of LoMYB65 caused dwarf phenotype,unnormal tapetum development,less seeds of siliques in transgenic Arabidopsis plants,the transgenic plants showed partly male sterile.Simultaneously,silencing of LoMYB65 with VIGS(Virus Induced Gene Silencing)in lily anthers caused unnormal pollen development and reduced the pollen amount.Overexpression of LoMYB65 in Arabidopsis and silencing of LoMYB65 in lily resulted in decreased pollen counts,so we speculate that LoMYB65 may be dose-dependent.Overall,these findings suggest that LoMYB65 may play an important role in anther development and pollen formation in lily.LoMYB65 may provide a useful candidate gene for pollenless breeding of lily.
基金financially supported by the National Natural Science Foundation of China (Grant Nos.32101571,32002071)the Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding (Grant No.2021C02071-6)。
文摘Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch.
