ИСТИНА

The most important model describing flower development is a widely known ABC model which explain how interactions of transcription regulators result in specification of floral organs. Many efforts were applied for deeper understanding of the ABC model on the past twenty years. Nevertheless for now little is known about genes downstream to regulators of ABC model. We performed large-scale analysis of gene expression in inflorescences of mutants ag-1, pi-1, ap3-6, ap2-7, ap2-1, ap1-1 by transcriptome sequencing (RNA-seq). Sequencing was performed using Illumina HiSeq2000 in two biological replicates. We obtained from 20 to 35 millions of reads for each sample and more than 97% of reads were successfully mapped to exons. R package DESeq was used for identifying differential expressed (DE) genes. The number of DE genes was from 1596 for ap1-1 to 4499 for ap3-6. To avoid false positive results caused by difference in ratio of different organs and tissues between objects being compared (so called pattern effect), DE genes were processed by the filter that we developed. Also this filter allows discovering genes specific for each type of floral organs. After filtration of genes prone to pattern effect genes regulated by ABC genes were identified. The number of such genes varies from 597 for ap1-1 to 1310 for ap3-6. With analysis of intersections between different genes’ sets genes controlled by single ABC gene or by group of ABC genes were found. Analysis of Gene Ontology enrichment of DE expressed genes reveals association between control of meristem maintenance and stress response genes. Also control of meristem activity as in case of AG and AP2 is linked with genes involved in membrane formation. This result raises hope that processes regulated by genes of ABC model can be deeply understood in light of new sequencing technologies.