Silhavy D, Maliga P
Waksman Institute, Rutgers, The State University of New Jersey, 190 Frelinghuysen Road, Piscataway, NJ 08854-8010, USA.
Curr Genet. 1998 Jul;34(1):67-70. doi: 10.1007/s002940050367.
Plastid promoter utilization was characterized in rice by mapping transcript 5'-ends in samples derived from leaves and cultured embryogenic cells. We have found that rbcL, atpB and the rRNA operon are transcribed by the plastid-encoded plastid RNA polymerase (PEP), while clpP is transcribed by the nucleus-encoded plastid RNA polymerase (NEP) in both chloroplasts and the non-green plastids of embryogenic cultured cells. This finding is in contrast to reports on BY2 tobacco, in which NEP promoter activity in cultured cells was enhanced relative to leaves, facilitating identification of NEP promoters which are undetectable in chloroplasts. Therefore, it appears that activation of plastid NEP promoters in rice is not essential for adaptation to cell culture.
通过绘制来自叶片和培养的胚性细胞的样本中转录本5′末端图谱，对水稻中质体启动子的利用情况进行了表征。我们发现，rbcL、atpB和rRNA操纵子由质体编码的质体RNA聚合酶（PEP）转录，而clpP在胚性培养细胞的叶绿体和非绿色质体中均由核编码的质体RNA聚合酶（NEP）转录。这一发现与关于BY2烟草的报道形成对比，在BY2烟草中，培养细胞中NEP启动子的活性相对于叶片有所增强，便于鉴定在叶绿体中无法检测到的NEP启动子。因此，看来水稻中质体NEP启动子的激活对于适应细胞培养并非必不可少。
