文部省 科学研究費補助金 新学術領域研究 植物発生ロジックの多元的開拓

PubMed ID 27345165 Pubmed 日付 2016/Jul/11
タイトル An Evolutionarily Conserved Plant RKD Factor Controls Germ Cell Differentiation.
ジャーナル Current biology : CB  2016/Jul/11  26(13)  1775-81 
著者 Koi Satoshi S,Hisanaga Tetsuya T,Sato Katsutoshi K,Shimamura Masaki M,Yamato Katsuyuki T KT,Ishizaki Kimitsune K,Kohchi Takayuki T,Nakajima Keiji K
抄録 In contrast to animals, in which the germ cell lineage is established during embryogenesis, plant germ cells are generated in reproductive organs via reprogramming of somatic cells. The factors that control germ cell differentiation and reprogramming in plants are poorly understood. Members of the RKD subfamily of plant-specific RWP-RK transcription factors have been implicated in egg cell formation in Arabidopsis based on their expression patterns and ability to cause an egg-like transcriptome upon ectopic expression [1]; however, genetic evidence of their involvement is lacking, due to possible genetic redundancy, haploid lethality, and the technical difficulty of analyzing egg cell differentiation in angiosperms. Here we analyzed the factors that govern germ cell formation in the liverwort Marchantia polymorpha. This recently revived model bryophyte has several characteristics that make it ideal for studies of germ cell formation, such as low levels of genetic redundancy, readily accessible germ cells, and the ability to propagate asexually via gemma formation [2, 3]. Our analyses revealed that MpRKD, a single RWP-RK factor closely related to angiosperm RKDs, is preferentially expressed in developing eggs and sperm precursors in M. polymorpha. Targeted disruption of MpRKD had no effect on the gross morphology of the vegetative and reproductive organs but led to striking defects in egg and sperm cell differentiation, demonstrating that MpRKD is an essential regulator of germ cell differentiation. Together with previous findings [1, 4-6], our results suggest that RKD factors are evolutionarily conserved regulators of germ cell differentiation in land plants.

 ゼニゴケ生殖細胞形成の論文

奈良先端科学技術大学院大学 植物発生シグナル 中島 敬二  投稿日時[2016-08-04 14:56:53]

植物に保存されたRKD転写因子が、生殖細胞形成の鍵因子であることをゼニゴケを用いて明らかにした論文です。ゼニゴケを用いることで、シロイヌナズナにおける遺伝子機能の冗長性や生殖細胞を観察することの困難を克服することができました。この研究成果は、本新学術領域の河内班との共同研究です。