Biodiversity Research Center, Academia Sinica, Nankang, Taipei, Taiwan.
Department of Horticulture and Biotechnology, Chinese Culture University, Shihlin, Taipei, Taiwan.
PLoS One. 2018 Oct 24;13(10):e0205265. doi: 10.1371/journal.pone.0205265. eCollection 2018.
Insect galls are atypical plant tissues induced by the invasion of insects. Compared to the host leaf, gall tissues lose photosynthetic ability, but have higher soluble sugar content. Although the physiological and biochemical regulation of gall tissues have been demonstrated, the mechanism of genetic regulation has only been analyzed in few studies.
In this study, the transcriptome of cup-shaped galls and its host leaf were de novo assembled. Cellular functional enrichment and differentially expressed gene groups in the gall tissues were analyzed. The genes associated with primary metabolism, including photosynthesis, cell wall turnover, and sugar degradation, were expressed differently in galls and leaves. The examination of gene expression demonstrated that the genes involved in brassinosteroid synthesis and responses exhibited a remarkable modulation in cup-shaped galls, suggesting a potential role of steroid hormones in regulating gall development.
This study revealed the genetic responses, including those involved in source-sink reallocation and phytohormone metabolism, of galls induced by a dipteran insect.
虫瘿是昆虫入侵引起的非典型植物组织。与宿主叶片相比，瘿组织丧失了光合作用能力，但可溶性糖含量更高。尽管已经证明了瘿组织的生理和生化调节，但遗传调节的机制仅在少数研究中进行了分析。
本研究对杯状瘿及其宿主叶片进行了从头组装转录组分析。分析了瘿组织中的细胞功能富集和差异表达基因群。与光合作用、细胞壁周转和糖降解等初级代谢相关的基因在瘿和叶片中的表达不同。基因表达的检测表明，参与油菜素内酯合成和反应的基因在杯状瘿中表现出显著的调节，表明甾体激素在调节瘿发育中可能发挥作用。
本研究揭示了由双翅目昆虫诱导的瘿的遗传反应，包括源-库再分配和植物激素代谢。
