Housekeeping Proteins: Limitations as References During Neuronal Differentiation

Abstract

The use of "Housekeeping proteins" as loading controls in western blots requires that they do not change their level of expression. However, deviations from this rule have been observed. This study investigated the expression of the commonly used proteins HSP60, -tubulin,  -actin and GAPDH by western blot during retinoic acid-induced differentia- tion of the embryonal carcinoma NTera-2 and the neuroblastoma SH-SY5Y cell lines. -actin was found to be a poor loading control, increasing significantly during differentiation, whereas HSP60 and GAPDH were the more evenly ex- pressed of those analysed. Our results underline the importance of selecting accurate loading controls in this biological context.