Hu Xian, Jalal Salma, Yao Mingxi, Bakke Oddmund, Margadant Felix, Sheetz Michael
Center for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway.
Department of Biosciences, University of Oslo, Oslo, Norway.
Front Cell Dev Biol. 2024 Jul 17;12:1430728. doi: 10.3389/fcell.2024.1430728. eCollection 2024.
This study investigates differences in focal adhesion (FA) morphology and Talin cleavage levels between transformed and non-transformed cell lines. Utilizing fluorescently tagged wild-type Talin and Talin mutants with calpain cleavage site mutations, FA structures were visualized. Mutations in different Talin cleavage sites showed varying impacts on FA morphology and distribution across melanoma cell lines (Meljuso, A375P, A2058) and a non-transformed cell line (HFF). Western blot analysis, ratiometric fluorescence intensity-based measurements, and FRAP experiments revealed higher Talin cleavage levels within FAs of transformed cell lines compared to non-transformed cells. Additionally, growth assays indicated that reducing calpain cleavage levels attenuated transformed cell growth. These findings suggest that Talin cleavage level is crucial for FA morphology and assembly, with higher levels observed in transformed cells, influencing their growth dynamics.
本研究调查了转化细胞系和未转化细胞系之间粘着斑（FA）形态和踝蛋白切割水平的差异。利用荧光标记的野生型踝蛋白和具有钙蛋白酶切割位点突变的踝蛋白突变体，对粘着斑结构进行了可视化。不同踝蛋白切割位点的突变对黑素瘤细胞系（Meljuso、A375P、A2058）和未转化细胞系（HFF）的粘着斑形态和分布产生了不同影响。蛋白质免疫印迹分析、基于比率荧光强度的测量以及荧光漂白恢复实验表明，与未转化细胞相比，转化细胞系粘着斑内的踝蛋白切割水平更高。此外，生长试验表明，降低钙蛋白酶切割水平会减弱转化细胞的生长。这些发现表明，踝蛋白切割水平对于粘着斑形态和组装至关重要，在转化细胞中观察到更高的水平，影响其生长动力学。
