Nemo-like kinase suppresses Notch signalling by interfering with formation of the Notch active transcriptional complex.
The Notch signalling pathway has a crucial function in determining cell fates in multiple tissues within metazoan organisms. On binding to ligands, the Notch receptor is cleaved proteolytically and releases its intracellular domain (NotchICD). The NotchICD enters the nucleus and acts cooperatively with other factors to stimulate the transcription of target genes. High levels of Notch-mediated transcriptional activation require the formation of a ternary complex consisting of NotchICD, CSL (CBF-1, suppressor of hairless, LAG-1) and a Mastermind family member. However, it is still not clear how the formation of the ternary complex is regulated. Here we show that Nemo-like kinase (NLK) negatively regulates Notch-dependent transcriptional activation by decreasing the formation of this ternary complex. Using a biochemical screen, we identified Notch as a new substrate of NLK. NLK-phosphorylated Notch1ICD is impaired in its ability to form a transcriptionally active ternary complex. Furthermore, knockdown of NLK leads to hyperactivation of Notch signalling and consequently decreases neurogenesis in zebrafish. Our results both define a new function for NLK and reveal a previously unidentified mode of regulation in the Notch signalling pathway.
Ishitani
Tohru
T
Unit on Nervous Development Systems, Nagoya 464-8602, Japan. tish@bioreg.kyushu-u.ac.jp
Hirao
Tomoko
T
Suzuki
Maho
M
Isoda
Miho
M
Ishitani
Shizuka
S
Harigaya
Kenichi
K
Kitagawa
Motoo
M
Matsumoto
Kunihiro
K
Itoh
Motoyuki
M
D019943:Amino Acid Substitution / Q000502:physiology; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D004247:DNA / Q000378:metabolism; D051959:ELAV Proteins / Q000378:metabolism; D000067778:ELAV-Like Protein 3; D004625:Embryo, Nonmammalian / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000235:genetics / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D055495:Neurogenesis / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D016376:Oligonucleotides, Antisense / Q000235:genetics; D010766:Phosphorylation / Q000502:physiology; D011485:Protein Binding / Q000502:physiology; D054730:Protein Interaction Domains and Motifs / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D051881:Receptor, Notch1 / Q000235:genetics / Q000378:metabolism; D051880:Receptors, Notch / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D000072056:Transcription Factor HES-1; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014981:Xenopus; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
D051792:Basic Helix-Loop-Helix Proteins; D004247:DNA; D051959:ELAV Proteins; D000067778:ELAV-Like Protein 3; D018398:Homeodomain Proteins; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; D047908:Intracellular Signaling Peptides and Proteins; D020928:Mitogen-Activated Protein Kinases; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D016376:Oligonucleotides, Antisense; D017346:Protein Serine-Threonine Kinases; D034741:RNA, Small Interfering; D051881:Receptor, Notch1; D051880:Receptors, Notch; D000072056:Transcription Factor HES-1; D014157:Transcription Factors; D029961:Zebrafish Proteins; C489734:Hes1 protein, mouse; C486455:Maml1 protein, mouse; C497761:NOTCH1 protein, human; C497762:Notch1 protein, mouse; C497571:Rbpj protein, mouse; C088635:elavl3 protein, zebrafish; C119433:her4.1 protein, zebrafish; C437805:notch1a protein, zebrafish; C470551:NLK protein, human; C408347:Nlk protein, mouse; C488360:nemo-like kinase, zebrafish