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A mitochondrial protein homologous to the mammalian peripheral‐type benzodiazepine receptor is essential for stress adaptation in plants
Author(s) -
Frank Wolfgang,
Baar KimMiriam,
Qudeimat Enas,
Woriedh Mayada,
Alawady Ali,
Ratnadewi Diah,
Gremillon Louis,
Grimm Bernhard,
Reski Ralf
Publication year - 2007
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1111/j.1365-313x.2007.03198.x
Subject(s) - hemin , physcomitrella patens , tetrapyrrole , biology , mitochondrion , microbiology and biotechnology , gene , heme , biochemistry , abiotic stress , mutant , enzyme
Summary The cloning of abiotic stress‐inducible genes from the moss Physcomitrella patens led to the identification of the gene PpTSPO1 , encoding a protein homologous to the mammalian mitochondrial peripheral‐type benzodiazepine receptor and the bacterial tryptophane‐rich sensory protein. This class of proteins is involved in the transport of intermediates of the tetrapyrrole biosynthesis pathway. Like the mammalian homologue, the PpTSPO1 protein is localized to mitochondria. The generation of PpTSPO1 ‐targeted moss knock‐out lines revealed an essential function of the gene in abiotic stress adaptation. Under stress conditions, the PpTSPO1 null mutants show elevated H 2 O 2 levels, enhanced lipid peroxidation and cell death, indicating an important role of PpTSPO1 in redox homeostasis. We hypothesize that PpTSPO1 acts to direct porphyrin precursors to the mitochondria for heme formation, and is involved in the removal of photoreactive tetrapyrrole intermediates.