FIGURE 4. Regional distribution of GPR91 and GPR99.
From the following article:
Citric acid cycle intermediates as ligands for orphan G-protein-coupled receptors
Weihai He, Frederick J.-P. Miao, Daniel C.-H. Lin, Ralf T. Schwandner, Zhulun Wang, Jinhai Gao, Jin-Long Chen, Hui Tian and Lei Ling
Nature 429, 188-193(13 May 2004)
doi:10.1038/nature02488
a, b, Q-RT–PCR analysis of GPR91 (a) and GPR99 (b) in mouse tissue. Data are shown as means 
s.e.m. for triplicate determinations. c, Localization of GPR91 and GPR99 in mouse kidney sections by in situ hybridization. Scale bar, 1 mm. d, Localization of GPR91 (black grains) in the proximal tubules. PT, proximal tubule; DT, distal tubule; glom, glomerulus. Sections were prestained with anti-calbindin (brown) before hybridizing to GPR91 probe. Periodic acid–Schiff (PAS) staining identified proximal tubules. Scale bar, 25 
m. e, f, Localization of GPR99 (black grains in e and white signals in f) in the distal tubules. Scale bar: 25 m (e); 0.25 mm (f).
