A novel distal convoluted tubule-specific Cre-recombinase driven by the NaCl cotransporter gene

Am J Physiol Renal Physiol. 2020 Sep 1;319(3):F423-F435. doi: 10.1152/ajprenal.00101.2020. Epub 2020 Jul 13.


Cre-lox technology has revolutionized research in renal physiology by allowing site-specific genetic recombination in individual nephron segments. The distal convoluted tubule (DCT), consisting of distinct early (DCT1) and late (DCT2) segments, plays a central role in Na+ and K+ homeostasis. The only established Cre line targeting the DCT is Pvalb-Cre, which is limited by noninducibility, activity along DCT1 only, and activity in neurons. Here, we report the characterization of the first Cre line specific to the entire DCT. CRISPR/Cas9 targeting was used to introduce a tamoxifen-inducible IRES-Cre-ERT2 cassette downstream of the coding region of the Slc12a3 gene encoding the NaCl cotransporter (NCC). The resulting Slc12a3-Cre-ERT2 mice were crossed with R26R-YFP reporter mice, which revealed minimal leakiness with 6.3% of NCC-positive cells expressing yellow fluorescent protein (YFP) in the absence of tamoxifen. After tamoxifen injection, YFP expression was observed in 91.2% of NCC-positive cells and only in NCC-positive cells, revealing high recombination efficiency and DCT specificity. Crossing to R26R-TdTomato mice revealed higher leakiness (64.5%), suggesting differential sensitivity of the floxed site. Western blot analysis revealed no differences in abundances of total NCC or the active phosphorylated form of NCC in Slc12a3-Cre-ERT2 mice of either sex compared with controls. Plasma K+ and Mg2+ concentrations and thiazide-sensitive Na+ and K+ excretion did not differ in Slc12a3-Cre-ERT2 mice compared with controls when sex matched. These data suggest genetic modification had no obvious effect on NCC function. Slc12a3-Cre-ERT2 mice are the first line generated demonstrating inducible Cre recombinase activity along the entire DCT and will be a useful tool to study DCT function.

Keywords: Cre recombinase; NaCl cotransporter; distal convoluted tubule; potassium; sodium.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Estrogen Antagonists / pharmacology
  • Gene Expression Regulation / drug effects
  • Kidney Tubules, Distal / enzymology*
  • Mice
  • Recombinases / genetics
  • Recombinases / metabolism*
  • Sodium Chloride Symporters / genetics
  • Sodium Chloride Symporters / metabolism*
  • Solute Carrier Family 12, Member 3 / genetics
  • Solute Carrier Family 12, Member 3 / metabolism
  • Tamoxifen / pharmacology


  • Estrogen Antagonists
  • Recombinases
  • Slc12a3 protein, mouse
  • Sodium Chloride Symporters
  • Solute Carrier Family 12, Member 3
  • Tamoxifen