Fig. 4.
RNA-binding properties of IRP1 in chicken versus murine cells.
Apparent (−2-ME) and total (+2-ME) IRP activities in chicken SCF progenitors and murine L cells (Ltk−) were compared by IRE/IRP EMSAs using IRE probes derived from pSPT-Fer and pSPT-TR34 (see “Materials and methods”). The PhosphoImages show the respective migration properties of IRP1 and IRP2. In multiple measurements, the accuracy of this assay was at least ± 12% provided a linear quantification method of the 32P signals, that is, PhosphoImage analysis, was used.