David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139.
Columbia Center for Human Development and Division of Pulmonary, Allergy and Critical Care, Department of Medicine, and.
Mol Biol Cell. 2021 Oct 1;32(20):ar1. doi: 10.1091/mbc.E21-01-0039. Epub 2021 Jul 14.
Multiciliated cells play critical roles in the airway, reproductive organs, and brain. Generation of multiple cilia requires both activation of a specialized transcriptional program and subsequent massive amplification of centrioles within the cytoplasm. The E2F4 transcription factor is required for both roles and consequently for multiciliogenesis. Here we establish that E2F4 associates with two distinct components of the centriole replication machinery, Deup1 and SAS6, targeting nonhomologous domains in these proteins. We map Deup1 and SAS6 binding to E2F4's N-terminus and show that this domain is sufficient to mediate E2F4's cytoplasmic role in multiciliogenesis. This sequence is highly conserved across the E2F family, but the ability to bind Deup1 and SAS6 is specific to E2F4 and E2F5, consistent with their shared roles in multiciliogenesis. By generating E2F4/E2F1 chimeras, we identify a six-residue motif that is critical for Deup1 and SAS6 binding. We propose that the ability of E2F4 and E2F5 to recruit Deup1 and/or SAS6, and enable centriole replication, contributes to their cytoplasmic roles in multiciliogenesis.
纤毛细胞在气道、生殖器官和大脑中发挥着关键作用。生成多个纤毛需要激活专门的转录程序，随后在细胞质中大量扩增中心粒。E2F4 转录因子对于这两个作用以及纤毛发生都很重要。在这里，我们确定 E2F4 与中心粒复制机制的两个不同组件 Deup1 和 SAS6 相关联，针对这些蛋白质中的非同源结构域。我们将 Deup1 和 SAS6 的结合映射到 E2F4 的 N 端，并表明该结构域足以介导 E2F4 在纤毛发生中的细胞质作用。该序列在整个 E2F 家族中高度保守，但与 Deup1 和 SAS6 结合的能力是 E2F4 和 E2F5 所特有的，这与其在纤毛发生中的共同作用一致。通过生成 E2F4/E2F1 嵌合体，我们确定了一个对 Deup1 和 SAS6 结合至关重要的六残基基序。我们提出，E2F4 和 E2F5 招募 Deup1 和/或 SAS6 的能力以及允许中心粒复制有助于它们在纤毛发生中的细胞质作用。
