Journal: Frontiers in Cell and Developmental Biology
Article Title: CG4928 Is Vital for Renal Function in Fruit Flies and Membrane Potential in Cells: A First In-Depth Characterization of the Putative Solute Carrier UNC93A
doi: 10.3389/fcell.2020.580291
Figure Lengend Snippet: CG4928 is evolutionary conserved and crucial for normal renal function in D. melanogaster . Related proteins to UNC93A were searched for using a hidden Markov model. (A) UNC93A had orthologs in A. aegypti , A. carolinensis , C. elegans , C. intestinalis , D. rerio, D. melanogaster , G. aculeatus , G. gallus , and M. musculus . Closest relatives were UNC93B1 and MFSD11. CG4928 was ubiquitously knocked down using Da-Gal4 . (B) CG4928 knockdown males and females developed edema in 28°C compared with Driver control and RNAi control. Bright-field images displaying the Malpighian tubules obtained from Driver control, RNAi control, and CG4928 knockdown females were captured where (C) CG4928 knockdowns showed an accumulation of yellow-colored pigments in the Malpighian tubules, close-up (C) I–III. Ramsay assay was performed on Malpighian tubules from adult females ( n = 50). Secretion rate was measured after 2 h of secretion, average secretion rate (±SD) was plotted, and differences were calculated using one-way ANOVA with Bonferroni’s corrections (* p < 0.05, ** p < 0.01, *** p < 0.001). (D) CG4928 knockdown flies had a lower secretion rate compared with controls. Body and hemolymph samples were collected to measure osmolality, differences in body and hemolymph weight, and concentrations of sodium and potassium. Then, 20 μl of hemolymph sample from adult flies ( CG4928 knockdown n = 500, Driver control n = 800, RNAi control n = 800) was collected to measure osmolality and sodium and potassium concentrations. (E) CG4928 knockdowns had lower osmolality. Body and hemolymph weight were measured in males and females ( n = 30); weight was calculated against the number of flies. Graphs represent mean (±SD); differences were calculated with Kruskal–Wallis and Dunn’s correction (* p < 0.05, ** p > 0.01, *** p > 0.001). CG4928 knockdown flies were heavier, (F) body and (G) hemolymph weight, than controls and were found to have (H) 38.7% higher concentration of sodium and 8.6% lower concentration of potassium. Ion levels in Malpighian tubules from adult females were measured using ICP-SFMS ( n = 2–3 per genotype, with Malpighian tubules from 60 flies in each). Data are plotted with a scatter plot; differences were calculated using unpaired t -test with Bonferroni’s correction (adjusted p -values: * p < 0.0492, ** p < 0.0099, *** p < 0.0001). CG4928 knockdown flies had altered levels of (I) boron, (J) cadmium, (K) cobalt, and (L) potassium.
Article Snippet: According to NCBI and the human protein atlas , UNC93B1 is abundantly expressed in the body, whereas UNC93A is mainly expressed in the digestive tract and the kidney ( ; ).
Techniques: Knockdown, Control, Concentration Assay
Li et al., 2015 ; 