Fig. 2

Grp78/BiP is expressed at higher levels in laminitic tissues. a. Representative Grp78/BiP immunoblot, reprobed for alpha-tubulin as a loading control. A band of ~ 78 kd co-migrates with the Hela (human) protein. b). Two commercial antibodies to Grp78/BiP yield qualitatively similar results. Each antibody detects upregulation of Grp78/BiP in Hela cells (human cell line) treated with brefeldin A (BFA) to induce ER stress (see Methods and (Additional file 9: Figure S1 and Additional file 10: Legend to Figure S1A)). Lanes in (A,B) are labeled as: control (C), EL front limb (F) and EL hind limb (H). (c). Box plot of normalized Grp78/BiP band intensities in control (n = 6), EL front limbs (=12) and EL hind limbs (n = 8). Horizontal lines represent the median value for each group. Grp78/BiP expression was not significantly different between controls and EL hind limbs (p = 0.77) d. Comparison of Grp78/BiP expression in paired samples (n = 8) from EL front and hind limbs from the same horses. The inset shows the 4 sample pairs with small differences in Grp78/BiP band intensities between EL front and hind limb samples. The same pattern is apparent in 3 of 4 pairs, where the value for Grp78/BiP level in the front limb is greater than that in the hind limb