Then the cryld - lacz was introduced into different hosts . analysis of activity of p - galactosidase showed that the cryld and crylab expressed differently in different hosts . comparison of expression of cryld with crylab in the same host revealed that different upstream and competition for < j - factor were involved in the difference of cryld and crylab expression 結(jié)果表明,在不同遺傳背景的菌株中, cry1d - lacz和cry1ab - lacz融合基因的表達(dá)完全不同,表明同一基因在不同菌株中轉(zhuǎn)錄調(diào)控不同,也許一些宿主專一性的因子參與了轉(zhuǎn)錄調(diào)控;而在同一菌株中cry1d - lacz和cry1ab - lacz的表達(dá)差異是由于上游區(qū)的不同以及競爭有限的因子所致。