Nanoparticle titanium dioxide affects the growth and microRNA expression of switchgrass (Panicum virgatum)

Abstract

Nanoparticle TiO₂ is a common chemical used in daily life. As increasing usage of TiO₂, it is becoming a potentially dangerous contaminant to the environment. However, the impact of TiO₂ is not well understood. In this paper, switchgrass was employed to investigate the impacts of nanoparticle TiO₂ on plant growth and development as well as the potential impact on the expression of microRNAs (miRNAs). TiO₂ significantly affected switchgrass seed generation as well as plant growth and development in a dose-dependent manner. Particularly, TiO₂ significantly inhibited root development. miRNA expressions were also significantly altered. Nanoparticle TiO₂ may regulate plant development through controlling the expression of certain miRNAs. Among the 16 tested miRNAs, the expression of some miRNAs, such as miR390 and miR399 was increased with increasing TiO₂ concentrations; the expression of some miRNAs, such as miR169 was decreased with increasing TiO₂ concentrations; the other miRNAs show different expression patterns.

Keywords: Nanoparticle; Plant development; Switchgrass; TiO(2); microRNA.