Analysis of gene expression characteristics before and after seed germination of Polygonatum cyrtonema

Abstract

Polygonatum cyrtonema seeds have a comprehensive dormancy phenomenon, and analyzing the changes of key genes before and after seeds germination plays an important role in exploring seed physiology and breaking dormancy. Based on high-throughput sequencing technology (Illumina HiSeq 2500), the transcriptome sequencing and bioinformatics analysis were carried out in four stages of P. cyrtonema seed germination with three biological replicates. The results were as follows: (1) A total of 388 231 Transcripts and 178 319 Unigenes were obtained by de novo assembly. (2) Among the 11 817 Unigenes with significant differences before and after germination, 6 405 were up-regulated and 5 412 were down-regulated. (3) Significant difference genes were enriched and analyzed in the GO enrichment analysis, and the differential expression up- and down-regulation Uningenes were main enriched in biological process and molecular function, which were mainly involved in metabolic processes and catalytic activities. (4) KEGG significant enrichment indicated that the differential expression genes were mainly enriched in ribosome, plant hormone signal transduction, starch and sucrose metabolism and other pathways; the up-regulated differential genes were mainly enriched in ribosome 231, plant hormone signal transduction 56, starch and sucrose metabolism 76 and others; the down-regulated differential genes were mainly enriched in phenylpropanoid biosynthesis 48 plant hormone signal transduction 48, starch and sucrose metabolism 48, and other pathways; a total of 40 differential genes were involved in the synthesis of auxin pathway key enzymes. Genes encoding sucrose phosphate synthase were down-regulated and genes encoding glycogen phosphorylase were up-regulated in starch and sucrose metabolic pathways. The above results preliminarily identify that plant hormone signal transduction and starch and sucrose metabolism play a key role before and after the germination of P. cyrtonema seeds, and clarify the key genes involved in these two pathways, which provide a reference for further research on the physiology, reproduction and breeding of P. cyrtonema seeds.

Keywords

• polygonatum cyrtonema
• seeds
• before and after germination
• genes
• expression characteristics