An Arabidopsis pex10 null mutant is embryo lethal, implicating peroxisomes in an essential role during plant embryogenesis.
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.
Sparkes
Imogen A
IA
Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT United Kingdom.
Brandizzi
Federica
F
Slocombe
Stephen P
SP
El-Shami
Mahmoud
M
Hawes
Chris
C
Baker
Alison
A
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000235:genetics*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics*; D018388:Codon, Terminator; D017353:Gene Deletion; D005804:Genes, Lethal; D017343:Genes, Plant / Q000235:genetics*; D006580:Genetic Carrier Screening; D006720:Homozygote; D026901:Membrane Transport Proteins; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D000074401:Peroxins; D020675:Peroxisomes / Q000235:genetics / Q000502:physiology*; D012639:Seeds / Q000235:genetics / Q000502:physiology*
D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D018388:Codon, Terminator; D026901:Membrane Transport Proteins; C477605:PEX10 protein, Arabidopsis; D000074401:Peroxins