title: Kruppel-like factor family genes are expressed during Xenopus embryogenesis and involved in germ layer formation and body axis patterning.
abstract: BACKGROUND
  Kruppel-like factors (Klfs) are a family of transcription factors consisting of 17 members in mammals, Klf1-Klf17, which are involved in fundamental cellular physiological procedures, such as cell proliferation, differentiation, and apoptosis. However, their functions in embryonic development have been poorly understood. Our previous study has demonstrated that the pluripotency factor Klf4 participates in germ layer formation and axis patterning of Xenopus embryos by means of the regulation of key developmental signals. In the present study, we further investigated comprehensively the expression and functions of the klf family genes, klf2, klf5, klf6, klf7, klf8, klf11, klf15, and klf17, during the embryogenesis of Xenopus laevis.
  
  
  RESULTS
  Spatio-temporal expression analyses demonstrate that these genes are transcribed both maternally and zygotically in Xenopus embryos, and during organogenesis and tissue differentiation, they are localized to a variety of placodes and tissues. Gain and loss of function studies manifest that Klf factors play different roles in germ layer formation and body axis patterning. Moreover, each Klf factor exhibits distinct regulatory effects on the expression of genes that are essential for germ layer formation and body axis patterning.
  
  
  CONCLUSIONS
  These results suggest that Klf factors are involved in the fine-tuning of these genes during early embryogenesis.
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Cao
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lu
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Xuena
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Zan
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Dong
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Wenshuang
authors.initials: W
authors.lastname: Jia
authors.affiliation: Model Animal Research Center of Nanjing University and MOE Key Laboratory of Model Animals for Disease Study, Pukou High-Tech Zone, Nanjing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Cao
mesh_terms: D000818:Animals; D019521:Body Patterning; D004625:Embryo, Nonmammalian / Q000378:metabolism*; D047108:Embryonic Development; D015870:Gene Expression; D055785:Gene Knockdown Techniques; D005855:Germ Layers / Q000196:embryology*; D051741:Kruppel-Like Transcription Factors / Q000235:genetics / Q000378:metabolism*; D005810:Multigene Family; D014981:Xenopus
chemical_list: D051741:Kruppel-Like Transcription Factors
keywords: African clawed frog; Klf factors; embryo; expression patterns; phenotypes