The Arabidopsis E3 Ubiquitin Ligase SP1 Targets to Chloroplasts, Peroxisomes, and Mitochondria

Dear Editor, Our recent work discovered a role of the Arabidopsis E3 ubiquitin ligase SP1 in peroxisome matrix protein import ([Pan et al., 2016][1]). Recently, a Letter to the Editor published in Plant Physiology raised criticism against the localization and function of SP1 in peroxisomes ([Ling