Expression Analysis Of Different Organs During Pineapple Fruit Development And Building A Pineapple Organic Specific Gene Expression Database For Further Studies

Pineapple(Ananas comosus)is one of four most important fruit tree around the world.It is also a regional characteristic fruit in South China,which bearing collective fruits.In-depth study of its fruit development has both market and academic value.Reports of pineapple fruit are focused on its mature flesh or using the pulp mixed with different organs as the research object.In this paper,the development of pineapple fruit was divided into three stages.At different developmental stages,different organs of fruit were separated,transcriptome library was constructed and sequenced,and the transcriptional expression profiles of different organs during pineapple fruit development were discussed.The main findings obtained are as follows:1.Different organs of the three stages of pineapple fruit development were sampled and sequenced by transcriptome.A total of 36 samples were sequenced to obtain approximately 150 Gb data,with each sample having reads of 30 M or more.2.An automatic pipeline was constructed to carry out quality control and mapping of the transcriptome data of pineapple fruit,and estimation the gene expression level.A total of 88.02%(23,789)of the genes from the pineapple genome annotation were covered.The number of genes expressed in each sample fluctuated between 18,000 and 20,000.3.Based on the TAU algorithm,an automatic pipeline was constructed to mine the constitutive expression genes and organ-specific expression genes of pineapple.273 constitutively expressed genes were obtained,including several common q RT-PCR internal reference genes,Actin(Aco011848.1,Aco018482.1)and EF-1α(Aco010306.1).A total of1,051 organic specific expressed genes were obtained,of which the stamen-specific genes were most abundant(286),followed by root-specific genes(170),leaves-specific genes(147).Based on the hypergeometric distribution,the organic preferentially expressed geneswere subjected to enrichment analysis and function prediction.4.Significant analysis of gene expression differences at different stages of fruit development was performed on 11 organs.A total of 1483～2730 differentially expressed genes were found.Among them,vegetative organs such as root(1483),stem(2181)and leaf(1603)have fewer differentially expressed genes,while genital organs such as ovule(2730),placenta(2723)and disk(2676)have more differentially expressed genes.5.An R language script was written to construct the gene co-expression network during the development of pineapple fruit development based on the WGCNA algorithm.A total of 18 gene modules were identified.Different modules have different expression patterns.Based on the module’s expression preferences and functional annotations,the main associated functions are discussed.In summary,this paper explores the changes in gene expression profiles during the development of pineapple fruit through morphological observation,organ resolution and transcriptome analysis.At the same time,through the construction of the pineapple organ-specific gene database database,the data generated by the work will be shared in a user-friendly way.So far,nearly 1,000 visits have been obtained.This will provide some data and theoretical references for the research of molecular biology of pineapple fruit development.