Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, 75014, France.
Inserm U1016, CNRS UMR8104, Cochin Institute, Paris, France.
Cell Microbiol. 2019 Mar;21(3):e12973. doi: 10.1111/cmi.12973. Epub 2018 Dec 5.
Constitutive c-Jun N-terminal kinase (JNK) activity characterizes bovine T and B cells infected with Theileria parva, and B cells and macrophages infected with Theileria annulata. Here, we show that T. annulata infection of macrophages manipulates JNK activation by recruiting JNK2 and not JNK1 to the parasite surface, whereas JNK1 is found predominantly in the host cell nucleus. At the parasite's surface, JNK2 forms a complex with p104, a GPI-(GlycosylPhosphatidylInositol)-anchor T. annulata plasma membrane protein. Sequestration of JNK2 depended on Protein Kinase-A (PKA)-mediated phosphorylation of a JNK-binding motif common to T. parva and a cell penetrating peptide harbouring the conserved p104 JNK-binding motif competitively ablated binding, whereupon liberated JNK2 became ubiquitinated and degraded. Cytosolic sequestration of JNK2 suppressed small mitochondrial ARF-mediated autophagy, whereas it sustained nuclear JNK1 levels, c-Jun phosphorylation, and matrigel traversal. Therefore, T. annulata sequestration of JNK2 contributes to both survival and dissemination of Theileria-transformed macrophages.
组成型 c-Jun N 端激酶(JNK)活性是感染巴贝斯虫的牛 T 和 B 细胞以及感染环形泰勒虫的 B 细胞和巨噬细胞的特征。在这里,我们表明,环形泰勒虫感染巨噬细胞通过将 JNK2而不是 JNK1募集到寄生虫表面来操纵 JNK 激活,而 JNK1主要存在于宿主细胞核内。在寄生虫表面,JNK2 与 p104 形成复合物,p104 是一种 GPI-(糖基磷脂酰肌醇)锚定的环形泰勒虫质膜蛋白。JNK2 的隔离取决于蛋白激酶 A(PKA)介导的 JNK 结合基序的磷酸化,该基序在 T. 中常见 parva 和一个含有保守 p104 JNK 结合基序的细胞穿透肽,竞争地消除了结合,随后释放的 JNK2 被泛素化和降解。JNK2 的细胞质隔离抑制了小线粒体 ARF 介导的自噬,而维持了核 JNK1 水平、c-Jun 磷酸化和基质胶穿透。因此,环形泰勒虫对 JNK2 的隔离有助于感染的巨噬细胞的存活和传播。