Willin/FRMD6 is part of a family of proteins with a 4.1 ezrin-radixin-moesin (FERM) domain. It has been identified as an upstream activator of the Hippo pathway and, when aberrant in its expression, is associated with human diseases and disorders. Even though Willin/FRMD6 was originally discovered in the rat sciatic nerve, most studies have focused on its functional roles in cells outside of the nervous system, where Willin/FRMD6 is involved in the formation of apical junctional cell-cell complexes and in regulating cell migration. Here, we investigate the biochemical and biophysical role of Willin/FRMD6 in neuronal cells, employing the commonly used SH-SY5Y neuronal model cell system and combining biochemical measurements with Elastic Resonator Interference Stress Micropscopy (ERISM). We present the first direct evidence that Willin/FRMD6 expression influences both the cell mechanical phenotype and neuronal differentiation. By investigating cells with increased and decreased Willin/FRMD6 expression levels, we show that Willin/FRMD6 not only affects proliferation and migration capacity of cells but also leads to changes in cell morphology and an enhanced formation of neurite-like membrane extensions. These changes were accompanied by alterations of biophysical parameters such as cell force, the organization of actin stress fibers and the formation of focal adhesions. At the biochemical level, changes in Willin/FRMD6 expression inversely affected the activity of the extracellular signal-regulated kinases (ERK) pathway and downstream transcriptional factor NeuroD1, which seems to prime SH-SY5Y cells for retinoic acid (RA)-induced neuronal differentiation.

Willin / FRMD6是具有4.1 ezrin-radixin-moesin（FERM）结构域的蛋白质家族的一部分。它已被鉴定为河马途径的上游激活剂，并且在其表达异常时与人类疾病和失调有关。尽管Willin / FRMD6最初是在大鼠坐骨神经中发现的，但大多数研究都集中在其在神经系统外部细胞中的功能上，其中Willin / FRMD6参与了顶端连接细胞-细胞复合物的形成和调节细胞。移民。在这里，我们研究了Willin / FRMD6在神经元细胞中的生化和生物物理作用，采用了常用的SH-SY5Y神经元模型细胞系统，并将生化测量结果与弹性谐振器干扰应力显微镜（ERISM）相结合。我们提供了Willin / FRMD6表达影响细胞机械表型和神经元分化的第一个直接证据。通过研究具有增加和减少的Willin / FRMD6表达水平的细胞，我们表明Willin / FRMD6不仅影响细胞的增殖和迁移能力，而且导致细胞形态的变化和神经突样膜延伸的形成增强。这些变化伴随着生物物理参数的改变，例如细胞力，肌动蛋白应激纤维的组织和粘着斑的形成。在生化水平上，Willin / FRMD6表达的变化反过来影响细胞外信号调节激酶（ERK）通路和下游转录因子NeuroD1的活性，