Fig. 8: Ciliary deficiency and EphA hyperphosphorylation block insulin secretion in human islets.
From: Glucose homeostasis is regulated by pancreatic β-cell cilia via endosomal EphA-processing
a RFP (red) expression in human primary islets (scale bar 50 µm) b Immunoblotting of pEPHA3 (Tyr 779), IFT88, and actin protein levels in primary human islets, mean ± s.d. c Glucose-stimulated insulin secretion on human primary islets expressing shIFT88 or scrambled RNA (N.C. RNA) from four different donors (prep ID:R229, n = 6, N.C.RNA high glucose: 2.5 ± 0.5 ng ng−1 μL−1 insulin/DNA; shIFT88 high glucose: 1.38 ± 0.37 ng ng−1 μL−1 insulin/DNA; p = 0.005 (t test); prep ID: R232, n = 6, N.C.RNA high glucose: 0.64 ± 0.11 ng ng−1 μL−1 insulin/DNA; shIFT88 high glucose: 0.28 ± 0.11 ng ng−1 μL−1 insulin/DNA; p = 0.002 (t test); prep ID:R230, n = 6, N.C.RNA high glucose: 0.79 ± 0.07 ng ng−1 μL−1 insulin/DNA; shIFT88 high glucose: 0.56 ± 0.12 ng ng−1 μL−1 insulin/DNA; p = 0.0023 (t test); prep ID: R233, n = 6, N.C.RNA high glucose: 0.56 ± 0.13 ng ng−1 μL−1 insulin/DNA; shIFT88 high glucose: 0.36 ± 0.06 ng ng−1 μL−1 insulin/DNA; p = 0.02 (t test) [R229 = 22 y/o, F, BMI = 23.0; R230 = 58 y/0, M, BMI = 29.4; R232 = 66 y/o, F, BMI = 18.5; R233 = 76 y/o, F, BMI = 19.3], mean ± s.d. d Immunoblotting of phosphorylated (Tyr 779), IFT88, and actin of primary human islets lysates [(R268 = 29.2 y/o, F, BMI = 29.2; R262 = 54 y/o, F, BMI = 22.; R263 = 71 y/o, M, BMI= 38.3; R259 = 45 y/o, F, BMI = 33.1; R271 = 60 y/o, F, BMI = 26.0], mean ± s.d.
