RT Journal Article SR Electronic T1 An Arabidopsis pex10 Null Mutant Is Embryo Lethal, Implicating Peroxisomes in an Essential Role during Plant Embryogenesis JF Plant Physiology JO Plant Physiol. FD American Society of Plant Biologists SP 1809 OP 1819 DO 10.1104/pp.103.031252 VO 133 IS 4 A1 Sparkes, Imogen A. A1 Brandizzi, Federica A1 Slocombe, Stephen P. A1 El-Shami, Mahmoud A1 Hawes, Chris A1 Baker, Alison YR 2003 UL http://www.plantphysiol.org/content/133/4/1809.abstract AB Peroxisomes participate in many important functions in plants, including seed reserve mobilization, photorespiration, defense against oxidative stress, and auxin and jasmonate signaling. In mammals, defects in peroxisome biogenesis result in multiple system abnormalities, severe developmental delay, and death, whereas in unicellular yeasts, peroxisomes are dispensable unless required for growth of specific substrates. PEX10 encodes an integral membrane protein required for peroxisome biogenesis in mammals and yeast. To investigate the importance of PEX10 in plants, we characterized a Ds insertion mutant in the PEX10 gene of Arabidopsis (AtPEX10). Heterozygous AtPEX10::dissociation element mutants show normal vegetative phenotypes under optimal growth conditions, but produce about 20% abnormal seeds. The embryos in the abnormal seeds are predominantly homozygous for the disruption allele. They show retarded development and some morphological abnormalities. No viable homozygous mutant plants were obtained. AtPEX10 fused to yellow fluorescent protein colocalized with green fluorescent protein-serine-lysine-leucine, a well-documented peroxisomal marker, suggesting that AtPEX10 encodes a peroxisomal protein that is essential for normal embryo development and viability.