Figure 3. Intrathyroidal expression and localization of the Mct8 protein.

(A) Immunoconfocal images from cryosections of thyroid glands prepared from WT and Mct8-KO mice colabeled with anti-Mct8 antibody (red) and PNA lectin (green). Merged images are shown overlaid on the differential interference contrast image. Mct8 immunolabeling was detected at the basolateral membrane of thyrocytes (arrow) of WT mice, while no labeling was detected in thyroid sections from Mct8-KO mice. PNA lectin labeled the thyrocyte plasma membranes in sections from both WT and Mct8-KO mice. F, follicle. Scale bars: 20 μm. (B) Immunoblot analysis of detergent-soluble protein lysates prepared from thyroid glands of WT and Mct8-KO mice probed with antibodies to Mct8 and to β-actin as a loading control. Samples from WT mice show a band of 52 kDa, corresponding to Mct8. This band was absent in samples from Mct8-KO mice.