Fig. 3. Expression of Meis-inactivating constructs reduces RPC proliferation and cyclin D1 expression. (A-E) HH15 chick eyes transfected with the listed expression constructs together with GFP (green) and stained for phosphorylated histone H3 (pH3, red). (A) Control siRNA construct containing a randomized targeting sequence. pH3⁺/GFP⁺ indicates percentage of transfected cells in mitosis. (F-J) HH15 chick eyes stained for cyclin D1 or cyclin D2 following transfection with the constructs indicated. (F,H) cyclin D1, (G,J) cyclin D2. (K-M) Retinae transfected with MeisEnR+GFP (K), GFP (L) or MeisEnR+GFP together with cyclin D1 (M), stained for GFP (green) and pH3 (red); cell nuclei are counterstained with DAPI (blue). The position of pH3-labeled cell nuclei is indicated in the right-hand and middle panels of K. (N) Percentage of cells in mitosis (y-axis) for each transfected construct (x-axis). (O-R) Expression of Ath5 (O,Q) following transfection with the constructs indicated. The boxed areas in O,Q are shown at high magnification in O',Q', respectively. F,G, H-J, O,P and Q,R show neighboring sections. (I,P,R) Transfection controls.