The Study on Cell Migration using Mouse Embryonic Fibroblasts derived from Fxyd5 Deficient Mouse

Abstract

Cell migration is a process that is an essential mechanism of maintaining cellular homeostasis, thus, contributes to diverse biological functions in the multicellular organism. Aberrant regulation of cell migration drives the progression of diverse diseases including lung fibrosis, autoimmune syndromes, neuronal migration disorders, and cancer metastasis. Therefore, identifications of the factors that control cell migration are important. FXYD domain-containing ion transport regulator 5 (FXYD5), a modulator of ion transport or Na, K-ATPase, is correlated with various types of cancers and is associated with cancer cell invasion. FXYD5 down-regulates E-cadherin and progress cancer metastasis. Although studies on FXYD5 in various types of cancer has been actively conducted, studies on biological function of FXYD5 in normal cells are insufficient. In this study, the biological roles of Fxyd5 on cell migration were examined using Fxyd5 knock-out mice. Mouse embryonic fibroblasts (MEFs) were isolated to compare between wild-type and knock-out of Fxyd5 (Fxyd5-/-) groups. Then, collective cell migration, single cell migration, and morphological changes of single cell were identified using wild-type and Fxyd5-/- MEFs. As a result, knock-out of Fxyd5 attenuated chemotaxis in response to chemoattractant gradient in transwell migration assay and prolonged in vitro wound closure time, indicating that deletion of Fxyd5 decreased collective cell migration, in wound-healing assay. Also, knock-out of Fxyd5 reduced single cell migration capacity by decreasing the speed and distance of moving cells. In light of this, further microscope observations revealed that depletion of Fxyd5 decreased the density and length of filopodia, which is a fundamental protrusive structure at the leading edge of motile cells. Taken together, Fxyd5 functions as an essential factor of collective cell migration and single cell migration. These results should help a better understanding of the biological functions of the Fxyd5 on cell migration.