Exon III splicing switch of fibroblast growth factor (FGF) receptor-2 and -3 can be induced by FGF-1 or FGF-2
Exon III splicing switch of fibroblast growth factor (FGF) receptor-2 and -3 can be induced by FGF-1 or FGF-2
复制标题
成纤维细胞生长因子 (FGF) 受体-2 和 -3 的外显子 III 剪接开关可由 FGF-1 或 FGF-2 诱导
作者：
E. Scotet;E. Houssaint
成纤维细胞生长因子受体（FGFR）的一个基本特征是存在多种可能的选择性剪接。其中之一涉及编码IG结构域3的C-末端一半的mRNA序列，其对应于配体结合位点的一部分：两个可选外显子IIIb和IIIc编码IG结构域3的C-末端一半。FGFR-2和FGFR-3中的IIIb/IIIc选择是严格组织特异性的，IIIb外显子仅在上皮细胞中表达。我们在此描述了在外源性和内源性FGF-1或FGF-2的影响下FGFR-2和FGFR-3从IIIb到IIIc的可逆转换。我们观察到FGF诱导的FGF受体外显子转换（i）早在暴露于FGF后1小时发生（ii）是受体介导的（iii）依赖于细胞融合，并显示与细胞周期的联系（iv）与上皮特性的可逆性丧失相关。这些结果支持FGF在调节选择性剪接的FGFR mRNA表达中的作用。
An essential feature of fibroblast growth factor receptors (FGFRs) is the existence of multiple possibilities of alternative splicing. One of these concerns sequences of the mRNA coding for the C-terminal half of Ig domain 3 which corresponds to a part of the ligand-binding site: two alternative exons, IIIb and IIIc, encode the C-terminal half of Ig domain 3. The IIIb/IIIc choice in the FGFR-2 and FGFR-3 is strictly tissue-specific, the IIIb exon being expressed exclusively in epithelial cells. We describe here a reversible switch from IIIb to IIIc for FGFR-2 and FGFR-3 under the influence of exogenous and endogenous FGF-1 or FGF-2. We observed that FGF-induced FGF receptor exon switching (i) occurred as early as 1 h after exposure to FGF (ii) was receptor-mediated (iii) was dependent on cell confluency and showed a link with the cell cycle (iv) was correlated with a reversible loss of epithelial properties. These results support a role for FGF in the regulation of expression of alternatively spliced FGFR mRNA.