RNA 加工是一种重要的转录后现象，可在翻译前提供必要的转录多样性复杂性。这一过程中的畸变可能会导致肿瘤发生，我们之前曾报道过骨巨细胞瘤 (GCTB) 中剪接改变的增加，该肿瘤携带组蛋白变体 H3.3 的突变，编码甘氨酸 34 取代色氨酸 (H3.3-G34W) 。 G34W 与多种剪接因子相互作用，尤其是反式作用剪接因子 hnRNPA1L2。为了更深入地了解 GCTB 和 H3.3-G34W 等基因 HeLa 细胞中的 RNA 加工，我们从 hnRNPA1L2 和 H3.3-G34W 相关 RNA 中生成了 RNA 免疫沉淀测序数据，该数据表明 80% 的基因区域重叠，并且经常注释为 E2F 转录因子结合位点。 H3.3-G34W 的 GCTB 和 HeLa 细胞中已知的 hnRNPA1L2 结合基序的剪接畸变显着富集（p 值 < 0.01）。这种剪接畸变与 hnRNPA1L2 敲除不同，后者显示出独立于 H3.3-G34W 的改变。具有功能意义的是，hnRNPA1L2 被重新分布以紧密匹配 H3.3 模式（可能由 G34W 驱动），并且分布到正常亲本细胞中未占据的位点。综上所述，我们的数据揭示了 hnRNPA1L2 和 H3.3-G34W 之间的功能重叠，可能对 GCTB 发病机制期间的 RNA 加工产生重大影响。这为未来的治疗干预方式提供了新的机会。© 2024。作者。

RNA processing is an essential post-transcriptional phenomenon that provides the necessary complexity of transcript diversity prior to translation. Aberrations in this process could contribute to tumourigenesis, and we have previously reported increased splicing alterations in giant cell tumor of bone (GCTB), which carries mutations in the histone variant H3.3 encoding glycine 34 substituted for tryptophan (H3.3-G34W). G34W interacts with several splicing factors, most notably the trans-acting splicing factor hnRNPA1L2. To gain a deeper understanding of RNA processing in GCTB and isogenic HeLa cells with H3.3-G34W, we generated RNA-immunoprecipitation sequencing data from hnRNPA1L2 and H3.3-G34W associated RNAs, which showed that 80% overlapped across genic regions and were frequently annotated as E2F transcription factor binding sites. Splicing aberrations in both GCTB and HeLa cells with H3.3-G34W were significantly enriched for known hnRNPA1L2 binding motifs (p value < 0.01). This splicing aberration differed from hnRNPA1L2 knockouts, which showed alterations independent of H3.3-G34W. Of functional significance, hnRNPA1L2 was redistributed to closely match the H3.3 pattern, likely driven by G34W, and to loci not occupied in normal parental cells. Taken together, our data reveal a functional overlap between hnRNPA1L2 and H3.3-G34W with likely significant consequences for RNA processing during GCTB pathogenesis. This provides novel opportunities for therapeutic intervention in future modus operandi.© 2024. The Author(s).