Building peroxisomes: perspectives on plant peroxins

Peroxisomes are dynamic organelles with diverse metabolic functions that are essential for life in plants and mammals. In humans, peroxisomal defects underlie peroxisome biogenesis disorders, which are often fatal. In plants, peroxisomes contribute to photorespiration and phytohormone production during plant development and are the sole site of fatty acid β-oxidation, which is critical for fat mobilization during germination. Despite their functional diversity, much of the machinery involved in building and maintaining peroxisomes is conserved across most eukaryotes. The model plant Arabidopsis thaliana is ideal for peroxisome studies due to its large peroxisomes, whole-organism and molecular assays for peroxisome function, and facile genetics. New applications of microscopy, computational modeling, and biochemistry have advanced the understanding of peroxisome biogenesis across eukaryotic life. These advances have generated insights into the functions of the proteins involved in peroxisome biogenesis, known as peroxins. Here, we review knowledge of Arabidopsis thaliana peroxins and discuss how new perspectives on peroxin functions across kingdoms inform future research on plant peroxisomes.