Analysis of the involvement of different carriers on Na+-independent Pi transport. A: real-time analysis of RNA expression of the indicated Slc26, Slc20, Slc17, and Slc34 family members. B: comparison of the relative abundance of the indicated RNAs after treatment with 1 or 4 mM Pi for 48 h. C: Pi transport after 48 h of small interfering (si)RNA transfections against the indicated Slc26 family members in Caco2BBE cells incubated with 1 or 4 mM Pi. C, nontransfected cells; C−, scrambled siRNA-transfected cells.