Integrin-linked kinase can facilitate syncytialization and hormonal differentiation of the human trophoblast-derived BeWo cell line
Integrin-linked kinase can facilitate syncytialization and hormonal differentiation of the human trophoblast-derived BeWo cell line
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DOI：
10.1186/1477-7827-7-51
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发表时间：
2009-05-22
影响因子：
4.4
通讯作者：
MacPhee, Daniel J.
中科院分区：
文献类型：
--
作者：
Butler, Trina M.;Elustondo, Pia A.;MacPhee, Daniel J.
背景资料：在滋养层分化的融合途径中，干绒毛细胞滋养层细胞增殖，子细胞分化并与现有的合体滋养层融合以维持多核层。整合素连接激酶（ILK）是高度表达在第1和第2个三月绒毛细胞滋养层细胞，但几乎检测不到合胞体滋养层，因此，我们研究了ILK的潜在作用，帮助滋养层fusion.Methods：ILK的时间/空间表达和活性的BeWo细胞进行syncytization免疫印迹和免疫荧光分析。BeWo细胞也用含有野生型或两种突变ILK cDNA构建体的pEGFP表达载体转染。然后通过E-钙粘蛋白免疫染色的存在或不存在对在合胞化条件下生长的转染细胞中细胞融合的发生率进行评分。β-hCG在转染细胞中的表达，一个标志物的syncytiotrophoblast激素分化，也进行了类似assessed.Results：ILK催化活性增加，ILK开始越来越多地定位于BeWo细胞核在syncytialization与增加的pAkt和Snail蛋白表达。与含有空载体或dn-ILK的细胞相比，在表达组成型活性（ca）-ILK的BeWo细胞中，合胞化也显著升高（p < 0.05）。结论：ILK介导的细胞内β-hCG的合成至少部分依赖于ILK的催化活性，而激素分化则依赖于ILK相关蛋白的相互作用和催化活性。这项研究表明，ILK在BeWo合胞和分化中起着新的作用，可能是通过ILK-Akt-Snail途径，并暗示ILK在体内绒毛细胞滋养层细胞的相同过程中。
Background: In the fusion pathway of trophoblast differentiation, stem villous cytotrophoblast cells proliferate and daughter cells differentiate and fuse with existing syncytiotrophoblast to maintain the multi-nucleated layer. Integrin-linked kinase (ILK) is highly expressed in 1st and 2nd trimester villous cytotrophoblast cells, yet barely detectable in syncytiotrophoblast, thus we examined the potential role of ILK in aiding trophoblast fusion.Methods: The temporal/spatial expression and activity of ILK were determined in BeWo cells undergoing syncytialization by immunoblot and immunofluorescence analyses. BeWo cells were also transfected with pEGFP expression vectors containing wildtype or two mutant ILK cDNA constructs. The incidence of cell fusion in transfected cells grown under syncytialization conditions was then scored by the presence or absence of E-cadherin immunostaining. Beta-hCG expression in transfected cells, a marker of syncytiotrophoblast hormonal differentiation, was also similarly assessed.Results: ILK catalytic activity increased and ILK began to increasingly localize to BeWo cell nuclei during syncytialization in correlation with increased pAkt and Snail protein expression. Syncytialization was also significantly elevated (p < 0.05) in BeWo cells expressing constitutively active (ca)-ILK vs cells containing empty vector or dn-ILK. Furthermore, cytoplasmic Beta-hCG expression markedly increased (p < 0.05) in cells expressing wt- and ca-ILK.Conclusion: ILK-facilitated syncytialization is dependent, at least in part, on ILK catalytic activity while hormonal differentiation appears dependent on both ILK-associated protein interactions and catalytic activity. This study demonstrates that ILK plays a novel role in BeWo syncytialization and differentiation, perhaps through an ILK-Akt-Snail pathway, and implicates ILK in the same process in villous cytotrophoblasts in vivo.