Sipl1 and Rbck1 are novel Eya1-binding proteins with a role in craniofacial development.
The eyes absent 1 protein (Eya1) plays an essential role in the development of various organs in both invertebrates and vertebrates. Mutations in the human EYA1 gene are linked to BOR (branchio-oto-renal) syndrome, characterized by kidney defects, hearing loss, and branchial arch anomalies. For a better understanding of Eya1's function, we have set out to identify new Eya1-interacting proteins. Here we report the identification of the related proteins Sipl1 (Shank-interacting protein-like 1) and Rbck1 (RBCC protein interacting with PKC1) as novel interaction partners of Eya1. We confirmed the interactions by glutathione S-transferase (GST) pulldown analysis and coimmunoprecipitation. A first mechanistic insight is provided by the demonstration that Sipl1 and Rbck1 enhance the function of Eya proteins to act as coactivators for the Six transcription factors. Using reverse transcriptase PCR (RT-PCR) and in situ hybridization, we show that Sipl1 and Rbck1 are coexpressed with Eya1 in several organs during embryogenesis of both the mouse and zebrafish. By morpholino-mediated knockdown, we demonstrate that the Sipl1 and Rbck1 orthologs are involved in different aspects of zebrafish development. In particular, knockdown of one Sipl1 ortholog as well as one Rbck1 ortholog led to a BOR syndrome-like phenotype, with characteristic defects in ear and branchial arch formation.
Leibniz Institute for Age Research-Fritz Lipmann Institute, Jena, Germany.
Kathrin
K
Landgraf
Frank
F
Bollig
Mark-Oliver
MO
Trowe
Birgit
B
Besenbeck
Christina
C
Ebert
Dagmar
D
Kruspe
Andreas
A
Kispert
Frank
F
Hänel
Christoph
C
Englert
D000818:Animals; D019280:Branchio-Oto-Renal Syndrome / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004622:Embryo, Mammalian / Q000033:anatomy & histology / Q000502:physiology; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology / Q000502:physiology; D006257:Head / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014018:Tissue Distribution; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
D002352:Carrier Proteins; D018398:Homeodomain Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; C099236:SIX1 protein, human; C554944:Sipl1 protein, mouse; C490947:Six1 protein, mouse; C498351:Six1 protein, zebrafish; D014157:Transcription Factors; D029961:Zebrafish Proteins; C425287:sharpin; C504507:RBCK1 protein, human; D044767:Ubiquitin-Protein Ligases; C104381:EYA1 protein, human; C501156:Eya1 protein, mouse; D017027:Protein Tyrosine Phosphatases; C501158:eya1 protein, zebrafish