High impact information on fn1

• During gastrulation, IMZ cells will spread and migrate on FN whereas presumptive pre-involuting mesoderm, vegetal pole endoderm, and animal cap ectoderm will not [1].
• This morphogenetic process involves cell adhesion to the extracellular matrix protein fibronectin (FN) [1].
• IMZ cell attachment to FN is mediated by the Arg-Gly-Asp (RGD) sequence located in the type III-10 repeat and by the Pro-Pro-Arg-Arg-Ala-Arg (PPRRAR) sequence in the type III-13 repeat of the Hep II domain [1].
• We isolated the Xenopus fibronectin gene (FN) promoter and found four putative LEF-TCF binding sites [2].
• Consistent with the lack of these transcription factors, the FN promoter was silent in the epithelial cells but was activated upon transfection of LEF-1 [2].

Biological context of fn1

• Apparently, interaction with the RGD cell-binding site of FN and concomitant spreading of head mesoderm cells is required for the stabilization of cell locomotion [3].
• These results suggest that the FN matrix potentiates synaptic transmission in response to PKA activation [4].
• Fibronectin (FN) is a highly conserved extracellular matrix protein that plays crucial roles in vertebrate embryogenesis [5].

Anatomical context of fn1

• These data suggest that mesoderm induction activates the position-specific recognition of the synergy site of FN in vivo [1].
• In premigratory stages of the crest, both in Xenopus (stage 22) and the axolotl (stage 25), FN was found subepidermally and in extracellular spaces around the neural tube, notochord and somites [6].
• FN is present in the embryonic ECM before the onset of neural crest migration.(ABSTRACT TRUNCATED AT 400 WORDS)[6]
• Normal gastrula cells lack integrin alpha4 and, correspondingly, are unable to adhere to the alpha4 ligand, the V-region of FN [7].
• In media supplemented with LM, FN or CO, the SPPs showed little change but the neurite bundle patterns were qualitatively different [8].

Associations of fn1 with chemical compounds

• It is shown that the adhesion of ectodermal cells is modified by their interaction with a heparin-binding domain of the FN molecule [9].
• Triflavin, an Arg-Gly-Asp-dependent disintegrin, inhibited potentiating action of isoproterenol in neurons grown on FN substratum, suggesting that integrin is involved in the potentiation of the PKA pathway in the regulation of acetylcholine (ACh) release [4].
• The substrates include plastic (UN), polylysine (PL), polyornithine (PO), laminin (LM), fibronectin (FN), and collagen type I (CO) [8].
• The adhesive glycoprotein fibronectin (FN), which is a component of the network of extracellular matrix fibrils on the inner surface of the blastocoel roof (BCR), has been proposed to play a major role in directing mesodermal cell migration during amphibian gastrulation [3].
• Serine and cysteinyl proteases play important roles in Fn disassembly caused by PKA activation, but not that caused by PKC inhibition [10].

Analytical, diagnostic and therapeutic context of fn1

• Fibronectin visualized by scanning electron microscopy immunocytochemistry on the substratum for cell migration in Xenopus laevis gastrulae [11].
• Fibronectin, a major component of the extracellular matrix is critical for processes of cell traction and cell motility [12].
• The soluble form of bovine Fn was bath-applied to the cell cultures, and fibroblasts changed the soluble form of Fn into the fibrillar form in a time-dependent manner [10].
• The distribution of fibronectin during the cell type conversion from iris into lens that occurs in newt lens regeneration was studied by immunofluorescence [13].

References