title: Proteomic analysis of fibroblastema formation in regenerating hind limbs of Xenopus laevis froglets and comparison to axolotl.
abstract: BACKGROUND
  To gain insight into what differences might restrict the capacity for limb regeneration in Xenopus froglets, we used High Performance Liquid Chromatography (HPLC)/double mass spectrometry to characterize protein expression during fibroblastema formation in the amputated froglet hindlimb, and compared the results to those obtained previously for blastema formation in the axolotl limb.
  
  
  RESULTS
  Comparison of the Xenopus fibroblastema and axolotl blastema revealed several similarities and significant differences in proteomic profiles. The most significant similarity was the strong parallel down regulation of muscle proteins and enzymes involved in carbohydrate metabolism. Regenerating Xenopus limbs differed significantly from axolotl regenerating limbs in several ways: deficiency in the inositol phosphate/diacylglycerol signaling pathway, down regulation of Wnt signaling, up regulation of extracellular matrix (ECM) proteins and proteins involved in chondrocyte differentiation, lack of expression of a key cell cycle protein, ecotropic viral integration site 5 (EVI5), that blocks mitosis in the axolotl, and the expression of several patterning proteins not seen in the axolotl that may dorsalize the fibroblastema.
  
  
  CONCLUSIONS
  We have characterized global protein expression during fibroblastema formation after amputation of the Xenopus froglet hindlimb and identified several differences that lead to signaling deficiency, failure to retard mitosis, premature chondrocyte differentiation, and failure of dorsoventral axial asymmetry. These differences point to possible interventions to improve blastema formation and pattern formation in the froglet limb.
authors: Nandini
authors: N
authors: Rao
authors: Fengyu
authors: F
authors: Song
authors: Deepali
authors: D
authors: Jhamb
authors: Mu
authors: M
authors: Wang
authors: Derek J
authors: DJ
authors: Milner
authors: Nathaniel M
authors: NM
authors: Price
authors: Teri L
authors: TL
authors: Belecky-Adams
authors: Mathew J
authors: MJ
authors: Palakal
authors: Jo Ann
authors: JA
authors: Cameron
authors: Bingbing
authors: B
authors: Li
authors: Xiaoping
authors: X
authors: Chen
authors: Department of Biology, and Center for Developmental and Regenerative Biology, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA. dstocum@iupui.edu.
authors: David L
authors: DL
authors: Stocum
mesh_terms: D000557:Ambystoma / Q000254:growth & development / Q000378:metabolism*; D000818:Animals; D001861:Bone Regeneration / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D018507:Gene Expression Regulation, Developmental; D006614:Hindlimb / Q000378:metabolism*; D013058:Mass Spectrometry; D040901:Proteomics; D015398:Signal Transduction; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis / Q000254:growth & development / Q000378:metabolism*
chemical_list: D029867:Xenopus Proteins