Role of plasma-membrane-bound sialidase NEU3 in clathrin-mediated endocytosis

RODRIGUEZ WALKER M.; VILCAES A.; GARBARINO-PICO, E.; DANIOTTI J.L.

PORTLAND PRESS LTD

Lugar: Londres; Año: 2015 vol. 470 p. 131 - 131

angliosides are sialic acid-containing glycosphingolipidsmainly expressed at the outer leaflet of the plasma membrane.Sialidase NEU3 is a key enzyme in the catabolism of gangliosideswith its up-regulation having been observed in human cancercells. In the case of CME (clathrin-mediated endocytosis),although this has been widely studied, the role of NEU3 andgangliosides in this cellular process has not yet been established.In the present study, we found an increased internalizationof Tf (transferrin), the archetypical cargo for CME, in cellsexpressing complex gangliosides with high levels of sialylation.The ectopic expression of NEU3 led to a drastic decrease inTf endocytosis, suggesting the participation of gangliosides inthis process. However, the reduction in Tf endocytosis causedby NEU3 was still observed in glycosphingolipid-depleted cells,indicating that NEU3 could operate in a way that is independentof its action on gangliosides. Additionally, internalization of α2-macroglob