title: Zebrafish KLF4 is essential for anterior mesendoderm/pre-polster differentiation and hatching.
abstract: Gene knockout studies of Krüppel-like factors (KLFs) in mice have shown essential roles in organogenesis. A screen for KLF family members in zebrafish identified many KLFs. One of these, zebrafish KLF4 (zKLF4) is the homologue of neptune, a Xenopus laevis KLF. zKLF4 is expressed from approximately 80% epiboly a patch of dorsal/anterior mesendodermal cells called the pre-polster and, subsequently, in the polster and hatching gland. Here we investigate the function of zKLF4 using morpholino-based antisense oligonucleotides. Knockdown of zKLF4 resulted in complete absence of hatching gland formation and subsequent hatching in zebrafish. In addition, there was early knockdown of expression of the pre-polster/anterior mesendoderm markers CatL, cap1, and BMP4. These results indicate zKLF4 is expressed within the pre-polster, an early mesendodermal site, and that it plays a critical role in the differentiation of these cells into hatching gland cells.
authors.affiliation: Queensland Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia.
authors.forename: Melissa R
authors.initials: MR
authors.lastname: Gardiner
authors.forename: David F
authors.initials: DF
authors.lastname: Daggett
authors.forename: Leonard I
authors.initials: LI
authors.lastname: Zon
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Perkins
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D004707:Endoderm / Q000378:metabolism / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000378:metabolism*; D016376:Oligonucleotides, Antisense; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000378:metabolism*
chemical_list: C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D016376:Oligonucleotides, Antisense; D029961:Zebrafish Proteins; C418487:klf4 protein, zebrafish