Disease relevance of Amfr

• Autocrine motility factor receptor (AMFR) is a cell surface glycoprotein of 78000 molecular weight (gp78), regulating cell motility signaling in vitro and metastasis in vivo [1].
• Expression of autocrine motility factor receptor in serum- and protein-independent fibrosarcoma cells: implications for autonomy in tumor-cell motility and metastasis [2].
• These results suggest the existence of an "autocrine motility cycle" which influences melanoma cell motility by gp78 activation, and production of second messengers which affect the cytoskeletal architecture and expression of the AMF receptor itself [3].

High impact information on Amfr

• Purified AMF stimulated B16-F1 cell migration in a dose-dependent fashion and bound directly in a protein-protein-binding assay to the AMF receptor, a cell surface glycoprotein of Mr 78,000 [glycoprotein (gp) 78] [4].
• Dynamin K44A expression further inhibits AMF-R-mediated endocytosis to the endoplasmic reticulum in untransformed and transformed NIH-3T3 cells [5].
• Adenoviral expression of caveolin-1 also induces caveolae in the transformed NIH-3T3 cells and reduces AMF-R-mediated endocytosis to the endoplasmic reticulum to levels observed in untransformed NIH-3T3 cells [5].
• Autocrine motility factor receptor (AMF-R) is stably localized to caveolae, and the cholesterol extracting reagent, methyl-beta-cyclodextrin, inhibits its internalization to the endoplasmic reticulum implicating caveolae in this distinct receptor-mediated endocytic pathway [5].
• Expression of the AMF receptor (AMF-R) in normal cells is regulated by cell contact whereas in transformed cells AMF-R is constitutively expressed irrespective of cell density [6].

Biological context of Amfr

• The cells stably expressing high levels of AMFR as a result of transfection displayed a complete morphological change and acquired the ability to grow even in low serum [1].
• Our findings provide a direct evidence that overexpression of the AMFR is associated with the acquisition of a transformation phenotype [1].
• On the other hand, AMF receptor activation induced significant decrease in overall serine-phosphorylation level of cellular proteins accompanied by serine phosphorylation of 200, 90, 78 and 65 kd proteins [7].

Anatomical context of Amfr

• Overexpression of autocrine motility factor receptor (AMFR) in NIH3T3 fibroblasts induces cell transformation [1].
• Caveolin-1 stabilizes the plasma membrane association of caveolae and thereby acts as a negative regulator of the caveolae-mediated endocytosis of AMF-R to the endoplasmic reticulum [5].

Associations of Amfr with chemical compounds

• Curiously, the rate of methyl-beta-cyclodextrin-sensitive endocytosis of AMF-R to the endoplasmic reticulum is increased in ras- and abl-transformed NIH-3T3 cells that express significantly reduced levels of caveolin and few caveolae [5].

Other interactions of Amfr

• However, alpha-MSH did neither prevent the secretion of AMF from B16-BL6 cells nor alter the expression level of AMF receptor (gp78) [8].

References