Cytological Observation and Transcriptome Comparative Analysis of Self-Pollination and Cross-Pollination in Dendrobium Officinale

Abstract

Dendrobium officinale is a rare and traditional medicinal plant with high pharmacological and nutritional value. The self-incompatibility mechanism of D. officinale reproductive isolation was formed in the long-term evolution process, but intraspecific hybridization of different germplasm resources leads to a large gap in the yield, quality, and medicinal value of D. officinale. To investigate the biological mechanism of self-incompatibility in D. officinale, cytological observation and the transcriptome analysis was carried out on the samples of self-pollination and cross-pollination in D. officinale. Results for self-pollination showed that the pollen tubes could grow in the style at 2 h, but most of pollen tubes stopped growing at 4 h, while a large number of cross-pollinated pollen tubes grew along the placental space to the base of ovary, indicating that the self-incompatibility of D. officinale may be gametophyte self-incompatibility. A total of 63.41 G basesum of D. officinale style samples from non-pollinated, self-pollination, and cross-pollination by RNA-seq were obtained, and a total of 1944, 1758, and 475 differentially expressed genes (DEGs) in the comparison of CK (non-pollinated) vs. HF (cross-pollination sample), CK vs. SF (self-pollination sample) and SF vs. HF were identified, respectively. Forty-one candidate genes related to self-incompatibility were found by function annotation of DEGs, including 6 Ca2+ signal genes, 4 armed repeat containing (ARC) related genes, 11 S-locus receptor kinase (SRK) related genes, 2 Exo70 family genes, 9 ubiquitin related genes, 1 fatty acid related gene, 6 amino acid-related genes, 1 pollen-specific leucine-rich repeat extensin-like protein (LRX) related gene and 1 lectin receptor-like kinases (RLKs) related gene, showed that self-incompatibility mechanism of D. officinale involves the interaction of multiple genes and pathways. The results can provide a basis for the study of the self-incompatibility mechanism of D. officinale, and provide ideas for the preservation and utilization of high-quality resources of D. officinale.

Transcriptomic analysis of genes related to alkaloid biosynthesis and the regulation mechanism under precursor and methyl jasmonate treatment in Dendrobium officinale

“…To date, a number of transcriptomic analyses have been performed for different reasons, such as the identification of genes associated with the biosynthesis of bioactive components (polysaccharides, flavonoids, alkaloids, and terpenes) (Ren et al, 2020;Wang 10.3389/fpls.2022Wang 10.3389/fpls. .941231 et al, 2020, flower development (He et al, 2020;Chen et al, 2021), and environmental responses (Jiang et al, 2020;Zhang et al, 2021). In this study, D. officinale PLBs treated with TIA precursors (Trp and S) and MeJA were used for transcriptome sequencing on the Illumina HiSeq platform.…”

Research Advances in Multi-Omics on the Traditional Chinese Herb Dendrobium officinale

“…In nature D. officinale generally forms few seeds potentially because of self-incompatibility. A total of 41 putative genes involved in self-incompatibility were identified, including six Ca 2+ signal genes and 11 S-locus receptor kinase (SRK) related genes ( Chen Y. et al, 2021 ), which supply helpful insights for genetic mechanisms and preservation of D. officinale resources. Moreover, D. officinale seeds are small and have limited energy reserves, and the symbiotic relationship between D. officinale and mycorrhizal fungi is beneficial for D. officinale .…”