| Lotus(Nelumbo nucifera L.)belongs to the family Nelumbonaceae,and is a perennial herbaceous species.It is one of the important basal dicot and contains both the traits of monocots and dicots.It is an ornamental and vegetable crop with high economic value.The ornamental value of lotus is mainly determined by the morphological characteristics of lotus,and its morphological characteristics mainly include two aspects: flower type and flower color.The shape of the flower organ is one of the important determinants of the flower type,which is composed of the shape,size and number of petals.Petalization of lotus stamens can lead to an increase in the number of lotus petals and cause changes in flower morphology.At present,there are few reports on the molecular mechanism of genes related to lotus stamen petaloid.The positioning of genes related to lotus stamen petaloid is of great significance for identifying the target gene that regulates petalization.The objective of this study was to map and analyze genes related to lotus stamen petaloid and to identify candidate genes that regulate lotus stamen petaloid.The main findings are as follows:1.Mapping candidate genesBased on the existing genetic linkage groups and phenotypic data,the candidate segment was located in linkage group 8 with a linkage interval of 6.5 c M-7.9 c M.There are 282 coding genes in this area,7 of which are related to development.2.Expression analysis of candidate segment genesExpression analysis of all genes in the candidate segment showed that8 genes were highly expressed in petals and 24 genes were expressed in normal stamens.Analysis of 7 gene expressions related to the development of stamen petals,XP＿010244752.1 gene expression in normal stamens was significantly higher than petaloid stamens and petal tissue.3.The exploring of candidate genes that may be involved in the regulation of stamen petaloid.By analyzing the transcriptome data of petaloid and normal stamens,a total of 1164 differentially expressed genes were found,of which 723 genes were up-regulated in petaloid stamens and 441 were down-regulated.15 differentially expressed genes were obtained in the expression analysis of petaloid stamens and normal medial petals,and these genes were upregulated in petaloid stamens.Among them,8 differentially expressed genes overlap(XP＿010258425.1,XP＿010275090.1,XP＿010251337.1,XP＿010267940.1,XP＿010278498.1,XP＿010243901.1,XP＿019052710.1,XP＿010265827.1).All the differentially expressed genes were functionally annotated,and a total of 143 transcription factors were found.These transcription factors were distributed in 29 families.Among them,b HLH,MYB,C2H2 and ERF had more differentially expressed genes,respectively 23,17,12 and 11 genes.At the same time,the transcription factor families YABBY,MADS,AP2 and MIKC＿MADS,which are closely related to flower growth and development,were found.Among them,the AG gene may be a key gene regulating stamen petaloid,and its expression in petaloid stamens and normal petals is significantly different.This study used genetic mapping and transcriptomics techniques to mine candidate genes for the regulation of lotus stamen petalization,which laid the foundation for the analysis of the regulation mechanism of lotus stamen petalization,while providing a theoretical basis for the development of new lotus varieties and breeding. |
PDF Full Text Request