title: Atypical PKC, regulated by Rho GTPases and Mek/Erk, phosphorylates Ezrin during eight-cell embryocompaction.
abstract: Phosphorylation of Ezrin T567 plays an important role in eight-cell embryo compaction. Yet, it is not clear how Ezrin phosphorylation is regulated during embryo compaction. Here, we demonstrated that inhibition of Mek/Erk or protein kinase C (PKC) signaling reduced the phosphorylation level of Ezrin T567 in eight-cell compacted embryos. Interestingly, the Rho GTPase inhibitor C3-transferase caused basolateral enrichment of atypical PKC (aPKC), as well as basolateral shift of phosphorylated Ezrin, suggesting aPKC may be a key regulator of Ezrin phosphorylation. Moreover, inhibition of PKC, but not Mek/Erk or Rho GTPases, affected the maintenance of Ezrin phosphorylation in compacted embryos. We further identified that aPKC is indeed required for Ezrin phosphorylation in eight-cell embryos. Taken together, Rho GTPases facilitate the apical distribution of aPKC and Ezrin. Subsequently, aPKC and Mek/Erk work together to promote Ezrin phosphorylation at the apical region, which in turn mediates the apical enrichment of filamentous actin, stabilizing the polarized apical region and allowing embryo compaction. Our data also suggested that aPKC might be the Ezrin kinase during eight-cell embryo compaction.
authors: The State Key Laboratory of Medicinal Chemical Biology, the 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics and College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China.
authors: Hongjie
authors: H
authors: Liu
authors: Zhaoting
authors: Z
authors: Wu
authors: Xianle
authors: X
authors: Shi
authors: Wenzhi
authors: W
authors: Li
authors: Chang
authors: C
authors: Liu
authors: Dekun
authors: D
authors: Wang
authors: Xiaoying
authors: X
authors: Ye
authors: Lin
authors: L
authors: Liu
authors: Jie
authors: J
authors: Na
authors: Hong
authors: H
authors: Cheng
authors: Lingyi
authors: L
authors: Chen
mesh_terms: D036002:ADP Ribose Transferases / Q000378:metabolism; D000199:Actins / Q000096:biosynthesis; D000818:Animals; D001905:Botulinum Toxins / Q000378:metabolism; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian / Q000378:metabolism*; D047108:Embryonic Development; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005260:Female; D005419:Flavonoids / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008813:Mice, Inbred ICR; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D015398:Signal Transduction; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000099149:Ezrin
chemical_list: D036002:ADP Ribose Transferases; D000199:Actins; D001905:Botulinum Toxins; D003598:Cytoskeletal Proteins; D048049:Extracellular Signal-Regulated MAP Kinases; D005419:Flavonoids; D020929:Mitogen-Activated Protein Kinase Kinases; D011493:Protein Kinase C; D020742:rhoA GTP-Binding Protein; D000099149:Ezrin; C063007:exoenzyme C3, Clostridium botulinum; C115015:PKC-3 protein; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one