Lal S K, Hannah L C
Program in Plant Molecular and Cellular Biology and Horticultural Sciences, University of Florida, Gainesville, Florida, 32611-0690, USA.
Biochem Biophys Res Commun. 1999 Aug 11;261(3):798-801. doi: 10.1006/bbrc.1999.1119.
The process by which transposable elements are spliced from the host gene transcripts remains poorly understood. We previously reported that a maize transposable element Ds (dissociation) and a copy of its host site duplication are perfectly spliced from the shrunken-2 transcript in the endosperm. Here, we have monitored splicing of the Ds element and its flanking Sh2 sequence following transient expression in maize suspension cells. The pattern of Ds splicing in suspension cells differs dramatically from that in the endosperm. In contrast to splicing in the endosperm, Ds in suspension cells was completely spliced from the transcripts using multiple donor and acceptor splice sites outside the element. In addition, noncanonical splice sites were utilized in suspension cells. Our results indicate that this difference in splicing is due to the context of Ds placement in the construct and/or to tissue specific differences in splicing.
转座元件从宿主基因转录本中剪接出来的过程仍知之甚少。我们之前报道过,玉米转座元件Ds(解离)及其宿主位点重复的一个拷贝从胚乳中的皱缩-2转录本中完美剪接出来。在这里,我们监测了Ds元件及其侧翼Sh2序列在玉米悬浮细胞中瞬时表达后的剪接情况。悬浮细胞中Ds剪接的模式与胚乳中的模式有很大不同。与胚乳中的剪接不同,悬浮细胞中的Ds是利用元件外的多个供体和受体剪接位点从转录本中完全剪接出来的。此外,悬浮细胞中还利用了非规范剪接位点。我们的结果表明,这种剪接差异是由于构建体中Ds的放置背景和/或剪接的组织特异性差异所致。