Expression of At MND1 in male and female meiocytes. RNA in-situ hybridization of AtMND1 anti-sense RNA to flower buds. (A-F,H) Transverse sections of anthers. (G,I) Transverse sections of pistils. (A) Increased levels of expression first detected in stage 4 anther locules. (B) Magnification of inset in (A) showing increased expression in sporogenous cells (arrowhead). (C,D) Stage 5 anthers showing strong expression in pollen mother cells and tapetum. (E) Stage 6 anther containing meiotic cells. (F) Expression declines at the tetrad stage. (G) Increased expression in megaspore mother cell. (H,I) Sense controls. Scale bar: 25 μm.