BMC Med Genet. 2013 Jun 28;14:65. doi: 10.1186/1471-2350-14-65.
Tensin3 is an intracellular cytoskeleton-regulating protein, the loss of which is associated with increased cell motility, as has been observed in some human cancers. A novel chromosomal translocation, t(2;7)(p13;p12), present in a patient with a complex syndromic phenotype, directly involves Tensin3 (TNS3) and EXOC6B genes. This translocation could impair the expression of Tensin3 and ExoC6B proteins, and potentially produce two novel fusion transcripts. In the present study, we have investigated the expression and phenotypic features of these potential products in cultured cells from the proband.
Skin fibroblasts isolated from the proband as well as an age-matched control were grown in cell culture. Cells were used for quantitative RT-PCR, western blot and immunofluorescent confocal microscopy, which determined Tensin3 gene and protein expression. Phase-contrast and confocal microscopy additionally revealed cellular phenotype differences. A scratch wound assay monitored by live cell imaging measured cellular migration rates.
The levels of Tensin3 at both mRNA and protein levels were lower in proband cells versus control fibroblasts. Proband cells displayed broader and shorter morphologies versus control fibroblasts, and immunofluorescent staining revealed additional Tensin3 expression along cytoskeletal filaments and the cell periphery only in control fibroblasts. In addition, proband fibroblasts showed a significantly higher migration rate than control cells over 24 h.
The phenotypic changes observed in proband cells may arise from TNS3 haploinsufficiency, causing partial loss of full-length Tensin3 protein. These results further expose a role for Tensin3 in cytoskeletal organisation and cell motility and may also help to explain the syndromic features observed in the patient.
Tensin3 是一种细胞内细胞骨架调节蛋白，其缺失与某些人类癌症中观察到的细胞迁移增加有关。在一位具有复杂综合征表型的患者中发现了一种新的染色体易位 t(2;7)(p13;p12)，该易位直接涉及 Tensin3 (TNS3) 和 EXOC6B 基因。这种易位可能会损害 Tensin3 和 ExoC6B 蛋白的表达，并可能产生两种新的融合转录本。在本研究中，我们研究了来自先证者的培养细胞中这些潜在产物的表达和表型特征。
从先证者中分离的皮肤成纤维细胞以及年龄匹配的对照细胞在细胞培养中生长。细胞用于定量 RT-PCR、western blot 和免疫荧光共聚焦显微镜，以确定 Tensin3 基因和蛋白表达。相差和共聚焦显微镜还揭示了细胞表型差异。通过活细胞成像监测划痕伤口测定测量细胞迁移率。
先证者细胞中 Tensin3 的 mRNA 和蛋白水平均低于对照成纤维细胞。与对照成纤维细胞相比，先证者细胞的形态更宽更短，免疫荧光染色仅在对照成纤维细胞中显示出额外的 Tensin3 沿着细胞骨架丝和细胞周围表达。此外，与对照细胞相比，先证者成纤维细胞在 24 小时内的迁移率显著更高。
先证者细胞中观察到的表型变化可能是由于 TNS3 杂合不足引起的，导致全长 Tensin3 蛋白部分缺失。这些结果进一步揭示了 Tensin3 在细胞骨架组织和细胞迁移中的作用，也可能有助于解释患者观察到的综合征特征。
