title: Peter Pan functions independently of its role in ribosome biogenesis during early eye and craniofacial cartilage development in Xenopus laevis.
abstract: The Xenopus oocyte possesses a large maternal store of ribosomes, thereby uncoupling early development from the de novo ribosome biosynthesis required for cell growth. Brix domain-containing proteins, such as Peter Pan (PPan), are essential for eukaryotic ribosome biogenesis. In this study, we demonstrate that PPan is expressed maternally as well as in the eye and cranial neural crest cells (NCCs) during early Xenopus laevis development. Depletion of PPan and interference with rRNA processing using antisense morpholino oligonucleotides resulted in eye and cranial cartilage malformations. Loss of PPan, but not interference with rRNA processing, led to an early downregulation of specific marker genes of the eye, including Rx1 and Pax6, and of NCCs, such as Twist, Slug and FoxD3. We found that PPan protein is localized in the nucleoli and mitochondria and that loss of PPan results in increased apoptosis. These findings indicate a novel function of PPan that is independent of its role in ribosome biogenesis.
authors.affiliation: Institute for Biochemistry and Molecular Biology, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Bugner
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Tecza
authors.forename: Susanne
authors.initials: S
authors.lastname: Gessert
authors.forename: Michael
authors.initials: M
authors.lastname: Kühl
mesh_terms: D000818:Animals; D017209:Apoptosis; D002356:Cartilage / Q000196:embryology*; D002466:Cell Nucleolus / Q000378:metabolism; D015536:Down-Regulation; D029721:Drosophila Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D004627:Embryonic Induction; D005123:Eye / Q000196:embryology*; D005136:Eye Proteins / Q000235:genetics; D051858:Forkhead Transcription Factors / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D057809:HEK293 Cells; D018398:Homeodomain Proteins / Q000235:genetics; D006801:Humans; D017403:In Situ Hybridization; D020287:In Situ Nick-End Labeling; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D009432:Neural Crest / Q000196:embryology; D054258:Neural Plate / Q000196:embryology; D020319:Oligodeoxyribonucleotides, Antisense; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors / Q000235:genetics; D016133:Polymerase Chain Reaction; D012097:Repressor Proteins / Q000235:genetics; D012270:Ribosomes / Q000378:metabolism*; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000235:genetics; D051879:Twist-Related Protein 1 / Q000235:genetics; D051153:Wnt Proteins / Q000378:metabolism; D029867:Xenopus Proteins / Q000235:genetics; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D005136:Eye Proteins; D051858:Forkhead Transcription Factors; D018398:Homeodomain Proteins; D036341:Intercellular Signaling Peptides and Proteins; D020319:Oligodeoxyribonucleotides, Antisense; D000071841:PAX6 Transcription Factor; C000605730:PAX6 protein, human; D051761:Paired Box Transcription Factors; C524416:Rax protein, Xenopus; D012097:Repressor Proteins; C000604407:SNAI1 protein, human; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; D051879:Twist-Related Protein 1; D051153:Wnt Proteins; D029867:Xenopus Proteins; C491003:foxd3b-A protein, Xenopus; C120177:ppan protein, Drosophila; C000604451:sna protein, Drosophila