Tion state of proteins. Phosphatases are widely expressed enzymes that mediate the functional regulation of many proteins, including some renal channels and transporters such as the inwardly rectifying K+ channel, Na+-K+Cl2 cotransporter (NKCC1), CFTR, epithelial Na+ channel (ENaC), aquaporin-2 (AQP2) and Na+/H+ exchanger 3 (NHE3) [30,31,32,33,34,35,36]. In general, these ions and water channels are responsible to maintain the urine normal volume and acidbase status under varying physiological conditions and are under direct or CB-5083 biological activity indirect phosphorylation state control [37,38]. It was shown that the prevention of phosphorylation of specific sites in AQP2 increases localization of AQP2 vesicles to the apical plasma membrane leading to water reabsorption and urine concentration [38]. Thus, we could speculate that the fact that 129P3/J mice excrete less urine could be possibly explained by the PP1-mediatedenhancement of AQP2 vesicles trafficking, 12926553 which should be confirmed in future studies. PDZK1 is a scaffold protein that connects plasma membrane proteins and regulatory components, regulating their surface expression in epithelial cells apical domains. 25331948 Within the kidney, PDZK1 is localized exclusively in the brush border of the proximal tubule and interacts with several renal proteins including NHE3, a Na-H exchanger, and CFEX, a Cl-anion exchanger [39]. These exchanger transporters play principal roles in the reabsorption of Na+ and Cl2 in the proximal tubule of the mammalian kidney. Besides regulating reabsorption of filtered solutes, PDZK1 also plays a direct and essential role in maintaining normal brush border expression and function of CFEX in the proximal tubule in vivo [39]. The diminished expression of PDZK1 in kidney of 129P3/J mice may indicate an undisclosed impaired ability of ion reabsorption by this strain, which is consistent with the lower volume of urine excreted by these mice. We conclude that the renal proteome indicates several specific target proteins, both strain and F-induced, which possibly regulate the water and F metabolism in kidney of mice with distinct susceptibilities to F. In addition, although we did not focus in the correlation between target kidney proteins and DF, we found that some of those changed proteins are also codified by chromosomes 2 (13 proteins: sarcosine dehydrogenase, catalase, sorbitol dehydrogenase, isovaleryl-CoA dehydrogenase, creatine kinase U-type, phosphotriesterase-related protein, proteasome subunit beta type7, adenoxylhomocysteinase, protein disulfide-isomerase A3, argininosuccinate synthase, glycine amidinotransferase, biliverdin reductase A and sorting nexin-5) and 11 (3 proteins: peroxisomal acyl-coenzyme A oxidase 1, ATP synthase subunit d and Rho GDP-dissociation inhibitor 1), previously characterized to determine susceptibility and resistance to DF in A/J and 129P3/J mice, Microcystin-LR site respectively [40,41]. This correlation may provide a database for future hypothesis-driven researches.Supporting InformationFigure S1 2D gel analysis of renal proteome. Representative 2D maps of control kidneys. Selected spots in green represent those with differential expression in the comparison between control A/J (A) vs control 129P3/J mice (B). In Figure B, spot identification numbers in boundaries or not represents increases or decreases in protein expression when compared to A/J, respectively (Figure A). Dashed lines represent unique spots in the AJ group (A) and 129P3/J group (B), regardless exposure.Tion state of proteins. Phosphatases are widely expressed enzymes that mediate the functional regulation of many proteins, including some renal channels and transporters such as the inwardly rectifying K+ channel, Na+-K+Cl2 cotransporter (NKCC1), CFTR, epithelial Na+ channel (ENaC), aquaporin-2 (AQP2) and Na+/H+ exchanger 3 (NHE3) [30,31,32,33,34,35,36]. In general, these ions and water channels are responsible to maintain the urine normal volume and acidbase status under varying physiological conditions and are under direct or indirect phosphorylation state control [37,38]. It was shown that the prevention of phosphorylation of specific sites in AQP2 increases localization of AQP2 vesicles to the apical plasma membrane leading to water reabsorption and urine concentration [38]. Thus, we could speculate that the fact that 129P3/J mice excrete less urine could be possibly explained by the PP1-mediatedenhancement of AQP2 vesicles trafficking, 12926553 which should be confirmed in future studies. PDZK1 is a scaffold protein that connects plasma membrane proteins and regulatory components, regulating their surface expression in epithelial cells apical domains. 25331948 Within the kidney, PDZK1 is localized exclusively in the brush border of the proximal tubule and interacts with several renal proteins including NHE3, a Na-H exchanger, and CFEX, a Cl-anion exchanger [39]. These exchanger transporters play principal roles in the reabsorption of Na+ and Cl2 in the proximal tubule of the mammalian kidney. Besides regulating reabsorption of filtered solutes, PDZK1 also plays a direct and essential role in maintaining normal brush border expression and function of CFEX in the proximal tubule in vivo [39]. The diminished expression of PDZK1 in kidney of 129P3/J mice may indicate an undisclosed impaired ability of ion reabsorption by this strain, which is consistent with the lower volume of urine excreted by these mice. We conclude that the renal proteome indicates several specific target proteins, both strain and F-induced, which possibly regulate the water and F metabolism in kidney of mice with distinct susceptibilities to F. In addition, although we did not focus in the correlation between target kidney proteins and DF, we found that some of those changed proteins are also codified by chromosomes 2 (13 proteins: sarcosine dehydrogenase, catalase, sorbitol dehydrogenase, isovaleryl-CoA dehydrogenase, creatine kinase U-type, phosphotriesterase-related protein, proteasome subunit beta type7, adenoxylhomocysteinase, protein disulfide-isomerase A3, argininosuccinate synthase, glycine amidinotransferase, biliverdin reductase A and sorting nexin-5) and 11 (3 proteins: peroxisomal acyl-coenzyme A oxidase 1, ATP synthase subunit d and Rho GDP-dissociation inhibitor 1), previously characterized to determine susceptibility and resistance to DF in A/J and 129P3/J mice, respectively [40,41]. This correlation may provide a database for future hypothesis-driven researches.Supporting InformationFigure S1 2D gel analysis of renal proteome. Representative 2D maps of control kidneys. Selected spots in green represent those with differential expression in the comparison between control A/J (A) vs control 129P3/J mice (B). In Figure B, spot identification numbers in boundaries or not represents increases or decreases in protein expression when compared to A/J, respectively (Figure A). Dashed lines represent unique spots in the AJ group (A) and 129P3/J group (B), regardless exposure.
