Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, F-35000 Rennes, France.
Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, F-35000 Rennes, France; Univ Rennes, CNRS, Inserm, BIOSIT-UMS 3480, US_S 018, F-35000 Rennes, France.
Biochem Biophys Res Commun. 2022 Oct 20;626:79-84. doi: 10.1016/j.bbrc.2022.07.073. Epub 2022 Jul 30.
CD44 mRNA contains nine consecutive cassette exons, v2 to v10. Upon alternative splicing, several isoforms are produced with different impacts on tumor biology. Here, we demonstrate the involvement of the RNA-binding proteins CELF1 and ELAVL1 in the control of CD44 splicing. We show by FRET-FLIM that these proteins directly interact in the nucleus. By combining RNAi-mediated depletion and exon array hybridization in HeLa cells, we observe that the exons v7 to v10 of CD44 are highly sensitive to CELF1 and ELAVL1 depletion. We confirm by RT-PCR that CELF1 and ELAVL1 together stimulate the inclusion of these exons in CD44 mRNA. Finally, we show in eight different tumor types that high expression of CELF1 and/or ELAVL1 is correlated with the inclusion of CD44 variable exons. These data point to functional interactions between CELF1 and ELAVL1 in the control of CD44 splicing in human cancers.
CD44 mRNA 包含九个连续的外显子盒，即 v2 到 v10。通过选择性剪接，可产生多种异构体，对肿瘤生物学产生不同的影响。在这里，我们证明了 RNA 结合蛋白 CELF1 和 ELAVL1 参与了 CD44 剪接的调控。通过 FRET-FLIM 实验，我们证明这些蛋白质在细胞核中直接相互作用。通过在 HeLa 细胞中结合 RNAi 介导的敲低和外显子芯片杂交实验，我们观察到 CD44 的 v7 到 v10 外显子对 CELF1 和 ELAVL1 的敲低非常敏感。通过 RT-PCR，我们证实 CELF1 和 ELAVL1 共同促进了这些外显子在 CD44 mRNA 中的包含。最后，我们在八种不同的肿瘤类型中表明，CELF1 和/或 ELAVL1 的高表达与 CD44 可变外显子的包含相关。这些数据表明 CELF1 和 ELAVL1 之间在人类癌症中 CD44 剪接的调控中存在功能相互作用。
