Gene Expression in Citrus Plant Cells Using Helios^® Gene Gun System for Particle Bombardment

To understand how Citrus tristeza virus (CTV) replicates and moves inside the plant, it is critical to study the cellular interactions and localization of its encoded proteins. However, due to technical limitations, so far these studies have been limited to the nonnatural host Nicotiana benthamiana.Particle bombardment is a physical method to deliver nucleic acid and other biomolecules into the cells directly. The Helios^® gene gun (Bio-Rad, Hercules, CA) is a handheld device that uses a low-pressure helium pulse to accelerate high-density, subcellular-sized particles into a wide variety of targets for in vivo and in vitro applications. Here, we describe a detail protocol for either transient or stable gene expression in citrus leaf cells using this gene gun. This protocol can be used to study protein-protein interactions and subcellular localization in different kinds of plant cells.