Figure 4. Investigating the role of Bcd in hb transcriptional events on the local scale.

(A) A zoom-in merged view of a nucleus showing a single detected hb intron dot (green) and Bcd intensities (red). (B) Shown are the probability density functions of Bcd pixel intensity, P(B _pix), inside the inactive nuclei (blue), the active nuclei (red), or the areas of the detected intron dot sites (green). Data from three different A-P positions are shown in different colors. (C) Ratio of P(B _pix) inside the areas of the detected intron dot sites to P(B _pix) within the active nuclei. A base line at ratio of 1 is drawn (see text for details). Different colors represent data at different A-P positions: x/L = 0.2∼0.22 (blue), x/L = 0.3∼0.32 (red) and x/L = 0.4∼0.42 (green).