Study of Seed Hair Growth in Populus Tomentosa, an Important Character of Female Floral Bud Development
June 2014
in “
BMC genomics
”
Populus tomentosa seed hair RNA-seq transcriptional changes placenta ovary cell nucleus endoreduplication cell cycle cell elongation cell wall modification cellulose synthesis cell wall biosynthesis transcription factors cell fate poplar RNA sequencing gene expression cell growth cell wall formation gene regulation
TLDR Poplar seed hairs grow from the placenta at the ovary base, with endoreduplication playing a key role in their development, and share similar cellulose synthesis processes with cotton fibers.
The study investigated the development of poplar seed hair, which is a nuisance in northern China. Researchers used paraffin sections to observe the initiation and elongation of seed hairs and employed RNA-seq technology to analyze transcriptional changes during their development. They discovered that seed hairs originate from the placenta at the base of the ovary, unlike cotton fibers that come from seed coat epidermal cells. The presence of an enlarged cell nucleus and the significant enrichment of the gene ontology term "endoreduplication" suggested that endoreduplication is a key mechanism for maintaining the uni-cellular structure of seed hairs. Transcriptome analysis identified genes involved in cell cycle, elongation, and wall modification, and found that cellulose synthesis and cell wall biosynthesis-related processes are similar to those in cotton fibers. Transcription factors showed stage-specific up-regulation, with a notable down-regulation during the mid-to-late stage of development, indicating potential novel mechanisms for regulating cell fate and elongation. This study provided detailed insights into the origin and molecular dynamics of poplar seed hair development, offering a valuable resource for understanding this biological process.