Open AccessGenes for the peptidoglycan synthesis pathway are essential for chloroplast division in moss
Author(s) -
Mariko Machida,
Katsuaki Takechi,
Hiroshi Sato,
Sung Jin Chung,
Haruko Kuroiwa,
Susumu Takio,
Motoaki Seki,
Kazuo Shinozaki,
Tomomichi Fujita,
Mitsuyasu Hasebe,
Hiroyoshi Takano
Publication year - 2006
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.0510693103
Subject(s) - physcomitrella patens , peptidoglycan , biology , plastid , chloroplast , arabidopsis thaliana , gene , nuclear gene , genetics , genome , mutant
The general consensus is that a cyanobacterium phagocytosed by a host cell evolved into the plastids of red and green algae, land plants, and glaucophytes. In contrast to the plastids of glaucophytes, which retain a cyanobacterial-type peptidoglycan layer, no wall-like structures have been detected in plastids from other sources. Although the genome ofArabidopsis thaliana contains five genes that are essential for peptidoglycan synthesis, MurE, MurG, two genes ford -Ala-d -Ala ligase (Ddl), and the gene for translocase I (MraY), their functions have not been determined. We report that the mossPhyscomitrella patens has nine homologous genes related to peptidoglycan biosynthesis: MurA, B, C, D, E, and F, Ddl, genes for the penicillin-binding protein Pbp, anddd -carboxypeptidase (Dac). Corroborating a computer prediction, analysis of the GFP fusion proteins with the N terminus of PpMurE or of PpPbp suggests that these proteins are located in the chloroplasts. Gene disruption of the PpMurE gene inP. patens resulted in the appearance of macrochloroplasts both in protonema and in leaf cells. Moreover, gene knockout of theP. patens Pbp gene showed inhibition of chloroplast division in this moss; however, no Pbp gene was found inA. thaliana .