Premium
Mitochondrial type‐I prohibitins of Arabidopsis thaliana are required for supporting proficient meristem development
Author(s) -
Van Aken Olivier,
Pečenková Tamara,
Van De Cotte Brigitte,
De Rycke Riet,
Eeckhout Dominique,
Fromm Hillel,
De Jaeger Geert,
Witters Erwin,
Beemster Gerrit T. S.,
Inzé Dirk,
Van Breusegem Frank
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.2007.03276.x
Subject(s) - prohibitin , biology , arabidopsis , meristem , microbiology and biotechnology , mitochondrion , arabidopsis thaliana , cell division , mitochondrial dna , mitochondrial biogenesis , genetics , transgene , wild type , gene , organelle biogenesis , biogenesis , mutant , cell
Summary The Arabidopsis thaliana genome expresses five evolutionarily conserved prohibitin (PHB) genes that are divided into type‐I ( AtPHB3 and AtPHB4 ) and type‐II ( AtPHB1 , AtPHB2 and AtPHB6 ) classes, based on their phylogenetic relationships with yeast PHB1 and PHB2, respectively. Yeast and animal PHBs are reported to have diverse roles in the cell cycle, mitochondrial electron transport, aging and apoptosis. All transcribed Arabidopsis PHB genes are primarily expressed in both shoot and root proliferative tissues, where they are present in mitochondrial multimeric complexes. Loss of function of the type‐I AtPHB4 had no phenotypic effects, while loss of function of the homologous AtPHB3 caused mitochondrial swelling, decreased meristematic cell production, increased cell division time and reduced cell expansion rates, leading to severe growth retardation. Double knockout atphb3 atphb4 plants were not viable, but transgenic lines overexpressing AtPHB3 or AtPHB4 showed leaf shape aberrations and an increased shoot branching phenotype. Genome‐wide microarray analysis revealed that both knockout and overexpression perturbations of AtPHB3 and AtPHB4 provoked an altered abundance of mitochondrial and stress‐related transcripts. We propose that plant type‐I PHBs take part in protein complexes that are necessary for proficient mitochondrial function or biogenesis, thereby supporting cell division and differentiation in apical tissues.