Induction of Multichotomous Branching by CLAVATA Peptide in Marchantia polymorpha
Induction of Multichotomous Branching by CLAVATA Peptide in Marchantia polymorpha
复制标题
DOI：
10.1016/j.cub.2020.07.016
复制
发表时间：
2020-10-05
期刊：
影响因子：
9.2
通讯作者：
Bowman, John L.
中科院分区：
文献类型：
--
作者：
Hirakawa, Yuki;Fujimoto, Toko;Bowman, John L.
陆地植物的一个关键创新是分生组织的进化，其中干细胞具有多个切割面（分裂面），在单倍体（配子体）和二倍体（孢子体）世代中均衍生出三维生长[1-3]。每个分生组织内都存在一个干细胞库，必须保持相对恒定的大小才能适当发育[4-6]。在开花植物中，二倍体世代的干细胞通过CLAVATA 3/胚胎周围区域相关（CLE）肽信号传导维持[7，8]。在地钱多形物中，单倍体体经历二歧分枝，这是来自分生组织的生长的祖先特征，其中两个等同的体轴通过干细胞分裂发育，由未知的分子机制调节。我们在这里表明，在M。在多形藻中，用MpCLE 2/CLAVATA 3（CLV 3）肽处理导致未分化的细胞在顶端分生组织中积累，以MpYUC 2表达为标志。去除MpCLE 2肽导致从积累的细胞的多分支。遗传分析表明，CLAVATA 1（MpCLV 1）受体，而不是WUSCHEL相关的HOMEOBOX（MpWOX）转录因子，负责MpCLE 2肽信号传导。在顶端分生组织中，MpCLV 1广泛表达于中央区域，包括MpYUC 2阳性区域，而MpCLE 2以与MpYUC 2相比在很大程度上互补的方式表达，表明MpCLE 2介导局部细胞间通讯。CLV 3/CLE肽是开花植物中二倍体干细胞的负调控因子，在M. polymorpha，暗示了这一途径在陆地植物体平面进化中的关键作用。
A key innovation in land plants was the evolution of meristems with stem cells possessing multiple cutting faces (division planes) from which three-dimensional growth is derived in both haploid (gametophyte) and diploid (sporophyte) generations [1-3]. Within each meristem exists a pool of stem cells that must be maintained at a relatively constant size for development to occur appropriately [4-6]. In flowering plants, stem cells of the diploid generation are maintained by CLAVATA3/EMBRYO SURROUNDING REGION-related (CLE) peptide signaling [7, 8]. In the liverwort Marchantia polymorpha, the haploid body undergoes dichotomous branching, an ancestral characteristic of growth derived from the meristem, in which two equivalent body axes are developed via stem cell division, regulated by unknown molecular mechanisms. We show here that in M. polymorpha, treatment with MpCLE2/CLAVATA3 (CLV3) peptide resulted in the accumulation of undifferentiated cells, marked by MpYUC2 expression, in the apical meristem. Removal of MpCLE2 peptide resulted in multichotomous branching from the accumulated cells. Genetic analysis demonstrated that the CLAVATA1 (MpCLV1) receptor, but not the WUSCHEL-related HOMEOBOX (MpWOX) transcription factor, is responsible for MpCLE2 peptide signaling. In the apical meristem, MpCLV1 was expressed broadly in the central region, including the MpYUC2-positive area, whereas MpCLE2 was expressed in a largely complementary manner compared to MpYUC2, suggesting MpCLE2 mediates local cell-to-cell communication. CLV3/CLE peptide, a negative regulator of diploid stem cells in flowering plants, acts as a haploid stem cell-promoting signal in M. polymorpha, implicating a critical role for this pathway in the evolution of body plan in land plants.