Detailed profile of bmo-let-7 accumulation from ova to the late fifth instar. (A). Expression profile from pre-laid egg (ova) to to early 3rd molt. In the first test, the oviduct attached to egg was not discarded. In the second test, the oviduct was completely removed. T-1 stand for the first test (Test 1), T-2 means the second test (Test 2). The mulberry leaf was mainly used as a control to eliminate the potential contamination. U6 and 5srRNA hybridizations were used as loading controls and levels of let-7 RNA are quantified relative to 5srRNA. (B). Expression profile from early 4th instar to day-7 5th instar. The female and male silkworms were differentiated on the basis of gonad while harvesting the materials. U6 and 5srRNA hybridizations were used as loading controls and levels of let-7 RNA are quantified relative to U6.