Multi-site Neurogenin3 Phosphorylation Controls Pancreatic Endocrine Differentiation.
Multi-site Neurogenin3 Phosphorylation Controls Pancreatic Endocrine Differentiation.
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DOI：
10.1016/j.devcel.2017.04.004
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发表时间：
2017-05-08
影响因子：
11.8
通讯作者：
Philpott A
中科院分区：
文献类型：
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作者：
Azzarelli R;Hurley C;Sznurkowska MK;Rulands S;Hardwick L;Gamper I;Ali F;McCracken L;Hindley C;McDuff F;Nestorowa S;Kemp R;Jones K;Göttgens B;Huch M;Evan G;Simons BD;Winton D;Philpott A
前神经转录因子神经生成素3（Ngn 3）在胰腺内分泌细胞分化中起关键作用，尽管Ngn 3蛋白的调节在很大程度上未被探索。在这里，我们表明，Ngn 3蛋白进行细胞周期蛋白依赖性激酶（Cdk）介导的磷酸化多个丝氨酸-脯氨酸位点。用Ngn 3的磷酸化突变体形式取代野生型蛋白质增加了α细胞的生成，这是发育中胰腺中形成的最早的内分泌细胞类型。此外，在存在升高的c-Myc的情况下，未磷酸化的Ngn 3维持成人β细胞中的胰岛素表达，并增强导管重编程期间的内分泌特化。从机制上讲，防止多位点磷酸化可以增强Ngn 3的稳定性和DNA结合，促进驱动分化的靶基因的表达增加。因此，Ngn 3的多位点磷酸化控制其在促增殖因子存在下促进胰腺内分泌分化和维持β细胞功能的能力，并且可以被操纵以促进和维持体外和体内内分泌分化。Ngn 3可以在多个丝氨酸-脯氨酸位点上磷酸化Un（der）磷酸化Ngn 3比野生型Ngn 3更稳定和活性Ngn 3磷酸化调节体内胰腺内分泌细胞的生成Un（der）磷酸化Ngn 3促进类器官中的内分泌细胞重编程Azzarelli et al.显示神经生成素3的多位点磷酸化调节发育期间的胰腺内分泌分化，以及在病理性促增殖线索存在下维持成体β细胞功能。结果表明，神经生成素3的去磷酸化可以改善体外β细胞生成，并有助于维持疾病中的胰岛功能。
The proneural transcription factor Neurogenin3 (Ngn3) plays a critical role in pancreatic endocrine cell differentiation, although regulation of Ngn3 protein is largely unexplored. Here we demonstrate that Ngn3 protein undergoes cyclin-dependent kinase (Cdk)-mediated phosphorylation on multiple serine-proline sites. Replacing wild-type protein with a phosphomutant form of Ngn3 increases α cell generation, the earliest endocrine cell type to be formed in the developing pancreas. Moreover, un(der)phosphorylated Ngn3 maintains insulin expression in adult β cells in the presence of elevated c-Myc and enhances endocrine specification during ductal reprogramming. Mechanistically, preventing multi-site phosphorylation enhances both Ngn3 stability and DNA binding, promoting the increased expression of target genes that drive differentiation. Therefore, multi-site phosphorylation of Ngn3 controls its ability to promote pancreatic endocrine differentiation and to maintain β cell function in the presence of pro-proliferation cues and could be manipulated to promote and maintain endocrine differentiation in vitro and in vivo. Ngn3 can be phosphorylated on multiple serine-proline sites Un(der)phosphorylated Ngn3 is more stable and active than wild-type Ngn3 Ngn3 phosphorylation regulates pancreatic endocrine cell generation in vivo Un(der)phosphorylated Ngn3 promotes endocrine cell reprogramming in organoids Azzarelli et al. show that multi-site phosphorylation of Neurogenin3 regulates pancreatic endocrine differentiation during development, and maintenance of adult β cell function in the presence of pathological pro-proliferative cues. The results suggest that dephosphorylation of Neurogenin3 may improve β cell generation in vitro and help maintain islet function in disease.