EjGASA6 promotes flowering and root elongation by enhancing gibberellin biosynthesis

The Gibberellic Acid-stimulated Arabidopsis(GASA)gene family is involved in the regulation of gene expression and plant growth,development,and stress responses.To investigate the function of loquat GASA genes in the growth and developmental regulation of plants,a loquat EjGASA6 gene homologous to Arabidopsis AtGASA6 was cloned.EjGASA6 expression was induced by gibberellin,and ectopic transgenic plants containing this gene exhibited earlier bloom and longer primary roots since these phenotypic characteristics are related to higher gibberellin content.Transcriptome analysis and qRT-PCR results showed that the expression levels of GA3ox1 and GA20ox1,which encode key enzymes in gibberellin biosynthesis,were significantly increased.Furthermore,we confirmed that EjGASA6 could promote the expression of GA20ox1 via the luciferase reporter system.Overall,our results suggest that EjGASA6 promotes blooming and main-root elongation by positively regulating gibberellin biosynthesis.These findings broaden our understanding of the role of GASAs in plant development and growth,and lay the groundwork for future research into the functions of EjGASA6 in regulating loquat growth and development.

Genome assembly of wild loquat (Eriobotrya japonica) and resequencing provide new insights into the genomic evolution and fruit domestication in loquat

Wild loquats(Eriobotrya japonica Lindl.)provide remarkable genetic resources for studying domestication and breeding improved varieties.Herein,we generate the first high-quality chromosome-level genome assembly of wild loquat,with 45791 predicted proteincoding genes.Analysis of comparative genomics indicated that loquat shares a common ancestor with apple and pear,and a recent whole-genome duplication event occurred in loquat prior to its divergence.Genome resequencing showed that the loquat germplasms can be distinctly classified into wild and cultivated groups,and the commercial cultivars have experienced allelic admixture.Compared with cultivated loquats,the wild loquat genome showed very few selected genomic regions and had higher levels of genetic diversity.However,whole-genome scans of selective sweeps were mainly related to fruit quality,size,and f lesh color during the domestication process.Large-scale transcriptome and metabolome analyses were further performed to identify differentially expressed genes(DEGs)and differentially accumulated metabolites(DAMs)in wild and cultivated loquats at various fruit development stages.Unlike those in wild loquat,the key DEGs and DAMs involved in carbohydrate metabolism,plant hormone signal transduction,f lavonoid biosynthesis,and carotenoid biosynthesis were significantly regulated in cultivated loquats during fruit development.These high-quality reference genome,resequencing,and large-scale transcriptome/metabolome data provide valuable resources for elucidating fruit domestication and molecular breeding in loquat.

Global Lysine Acetylome Analysis of Flower Bud Development in Catalpa bungei

Lysine acetylation,a reversible and dynamic post-translational modification,plays pivotal roles in regulating many biological processes in plants.However,the information of lysine acetylation during flower development of woody angiosperm remains unclear.Herein,we identified a total of 667 lysine acetylation sites in 467 proteins in flower buds of Catalpa Bungei.The acetylated proteins were mainly involved in the pathways of carbon metabolism,glycometabolism and oxidative phosphorylation.Using functional enrichment analysis,61 and 13 acetylated proteins were involved in the glycometabolism and oxidative phosphorylation pathways,respectively.This suggests that lysine acetylated proteins play critical roles in the energy metabolism pathways.Accordingly,the protein–protein interactions were also highly enriched in the carbon metabolic pathway.Integrative analysis of lysine acetylome and transcriptome showed that transcript level changes of seven key lysine-acetylated proteins/genes involved in energy metabolism were significant different during floral transition.Importantly,compared with the normal flowering variety,the expression levels of phosphoribulokinase,phosphoenolpyruvate carboxykinase,ATP synthase and pyruvate dehydrogenase complex genes were significantly up-regulated at the stages of vegetative and transition buds during early flowering of C.bungei.These data represent the first lysine acetylome in the C.bungei flowers,and can serve as an essential basis for exploring the function of lysine acetylated proteins in the flower bud development of plants.