Expression of the Arabidopsis thaliana histone gene AtHTA1 enhances rice transformation efficiency.

We expressed the Arabidopsis thaliana histone AtHTA1 in rice under the control of the maize ubiquitin promoter. Transformation efficiencies of rice plants that constitutively expressed AtHTA1 were 28-44% higher than calli containing an empty vector control. Furthermore, co-infection of rice calli with a vector containing AtHTA1 and another vector with the target gene increased transformation by 27-50%. Thus, expression of AtHTA1 either transiently or in stably transformed cells improved rice transformation efficiency.