Fig. 1

Analysis of TRPP2 in normal and ADPKD cells by Western blotting. a TRPP2 is expressed in two different normal kidney cell lines (4/5 and HEK293) as well as in T and B lymphocytes generated by healthy controls (TL and LCL, respectively). TRPP2 expression, is lower in T lymphocytes compared with the other cell types (0.49 ± 0.12 for TL, 0.89 ± 0.21 for LCL, 1.31 ± 0.36 for HEK and 2.14 ± 0.16 for 4/5 cells. TL vs LCL, HEK and 4/5: * p < 0.05, ** p < 0.01 and *** p < 0.001, respectively). Data represent the mean ± standard deviation obtained from two different experiments in duplicate. Statistical significance was calculated by using the unpaired t-test. b T lymphocytes derived from ADPKD2 subjects carrying R872X mutation synthesise a stable truncated protein detectable by Western blotting. TM = transmembrane domain; EF = EF hand domain; CC = coiled coil motif. c TRPP2 expression is lower in T lymphocytes of ADPKD2 subjects compared with non-genetically defined ADPKD, ADPKD1 and control subjects (0.50 ± 0.18 in PKD2, 1.01 ± 0.26 in PKD1, 0.88 ± 0.29 in PKD, 0.97 ± 0.28 in RRT and 1.0 ± 0.35 in CTRL cells. PKD2 vs CTRL: ***p < 0.001). CTRL = healthy controls (n = 10); RRT = non-ADPKD subjects undergoing renal replacement therapy (n = 14); PKD = non-genetically defined ADPKD subjects (n = 12); PKD1 = ADPKD1 subjects (n = 11); PKD2 = ADPKD2 subjects (n = 16).TRPP2 values were calculated as ratio between the band intensity of TRPP2 and β-actin. Bars of graph C represent the values of TRPP2 (mean ± standard deviation) calculated as ratio between TRPP2 levels of different samples and the average of those obtained from healthy controls (CTRL). The values of TRPP2 and PC1 expression in analysed ADPKD subjects and controls are inserted in Additional file 2: Table S2