title: Protein inhibitor of activated STAT3 (PIAS3) protein promotes SUMOylation and nuclear sequestration of the intracellular domain of ErbB4 protein.
abstract: ErbB4 is a receptor tyrosine kinase implicated in the development and homeostasis of the heart, central nervous system, and mammary gland. Cleavable isoforms of ErbB4 release a soluble intracellular domain (ICD) that can translocate to the nucleus and function as a transcriptional coregulator. In search of regulatory mechanisms of ErbB4 ICD function, we identified PIAS3 as a novel interaction partner of ErbB4 ICD. In keeping with the small ubiquitin-like modifier (SUMO) E3 ligase function of protein inhibitor of activated STAT (PIAS) proteins, we showed that the ErbB4 ICD is modified by SUMO, and that PIAS3 stimulates the SUMOylation. Upon overexpression of PIAS3, the ErbB4 ICD generated from the full-length receptor accumulated into the nucleus in a manner that was dependent on the functional nuclear localization signal of ErbB4. In the nucleus, ErbB4 colocalized with PIAS3 and SUMO-1 in promyelocytic leukemia nuclear bodies, nuclear domains involved in regulation of transcription. Accordingly, PIAS3 overexpression had an effect on the transcriptional coregulatory activity of ErbB4, repressing its ability to coactivate transcription with Yes-associated protein. Finally, knockdown of PIAS3 with siRNA partially rescued the inhibitory effect of the ErbB4 ICD on differentiation of MDA-MB-468 breast cancer and HC11 mammary epithelial cells. Our findings illustrate that PIAS3 is a novel regulator of ErbB4 receptor tyrosine kinase, controlling its nuclear sequestration and function.
authors.affiliation: MediCity Research Laboratory and Department of Medical Biochemistry and Genetics, University of Turku, 20520 Turku, Finland.
authors.forename: Maria
authors.initials: M
authors.lastname: Sundvall
authors.forename: Anna
authors.initials: A
authors.lastname: Korhonen
authors.forename: Katri
authors.initials: K
authors.lastname: Vaparanta
authors.forename: Julius
authors.initials: J
authors.lastname: Anckar
authors.forename: Kalle
authors.initials: K
authors.lastname: Halkilahti
authors.forename: Zaidoun
authors.initials: Z
authors.lastname: Salah
authors.forename: Rami I
authors.initials: RI
authors.lastname: Aqeilan
authors.forename: Jorma J
authors.initials: JJ
authors.lastname: Palvimo
authors.forename: Lea
authors.initials: L
authors.lastname: Sistonen
authors.forename: Klaus
authors.initials: K
authors.lastname: Elenius
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000502:physiology*; D000818:Animals; D001943:Breast Neoplasms; D019556:COS Cells; D002467:Cell Nucleus / Q000378:metabolism; D002522:Chlorocebus aethiops; D066246:ErbB Receptors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005260:Female; D057809:HEK293 Cells; D006801:Humans; D042361:Mammary Glands, Human / Q000166:cytology / Q000378:metabolism; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D000075223:Poly-ADP-Ribose Binding Proteins; D000071156:Promyelocytic Leukemia Protein; D050828:Protein Inhibitors of Activated STAT / Q000235:genetics / Q000378:metabolism*; D054730:Protein Interaction Domains and Motifs / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000502:physiology; D034741:RNA, Small Interfering / Q000235:genetics; D066247:Receptor, ErbB-4; D015398:Signal Transduction / Q000502:physiology; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism; D058207:Sumoylation / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism
chemical_list: D018832:Molecular Chaperones; D009687:Nuclear Proteins; C484745:PIAS3 protein, human; C485891:PIAS4 protein, human; D000075223:Poly-ADP-Ribose Binding Proteins; D000071156:Promyelocytic Leukemia Protein; D050828:Protein Inhibitors of Activated STAT; D034741:RNA, Small Interfering; C117909:SUMO2 protein, human; D025841:Small Ubiquitin-Related Modifier Proteins; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human; C587689:ERBB4 protein, human; D066246:ErbB Receptors; D066247:Receptor, ErbB-4