Keiko Sakakibara, Sayuri Ando, Hoichong Karen Yip, Yosuke Tamada, Yuji Hiwatashi, Takashi Murata, Hironori Deguchi, Mitsuyasu Hasebe, John L Bowman
Department of Biological Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan. bara@hiroshima-u.ac.jp
Science (New York, N.Y.) 2013 Mar 1Unlike animals, land plants undergo an alternation of generations, producing multicellular bodies in both haploid (1n: gametophyte) and diploid (2n: sporophyte) generations. Plant body plans in each generation are regulated by distinct developmental programs initiated at either meiosis or fertilization, respectively. In mosses, the haploid gametophyte generation is dominant, whereas in vascular plants-including ferns, gymnosperms, and angiosperms-the diploid sporophyte generation is dominant. Deletion of the class 2 KNOTTED1-LIKE HOMEOBOX (KNOX2) transcription factors in the moss Physcomitrella patens results in the development of gametophyte bodies from diploid embryos without meiosis. Thus, KNOX2 acts to prevent the haploid-specific body plan from developing in the diploid plant body, indicating a critical role for the evolution of KNOX2 in establishing an alternation of generations in land plants.
Keiko Sakakibara, Sayuri Ando, Hoichong Karen Yip, Yosuke Tamada, Yuji Hiwatashi, Takashi Murata, Hironori Deguchi, Mitsuyasu Hasebe, John L Bowman. KNOX2 genes regulate the haploid-to-diploid morphological transition in land plants. Science (New York, N.Y.). 2013 Mar 1;339(6123):1067-70
PMID: 23449590
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