Alu Tandem Sequences Inhibit GFP Gene Expression by Triggering Chromatin Wrapping

作者：Wang Xiu Fang; Wang Xiaoyan; Liu Jing; Feng Jingjing; Mu Wenli; Shi Xiaojuan; Yang QnQing; Duan Xiaocui; Xie Ying; Lu Zhanjun^*

来源：Genes & Genomics, 2009, 31(3): 209-215.

DOI：10.1007/bf03191192

• Alu
• GFP
• chromatin wrapping
• premature transcriptional termination

Alu elements belonging to the short interspersed nuclear elements (SINE) of repetitive elements are present in more than one million copies which altogether represent 10% of the whole human genome. In this study, the roles of Alu tandem sequences in the process of GFP gene (GFP) expression and packing into chromatin of its DNA were studied. To detect the effect of Alu repeats on gene expression, different copies of Alus were inserted GFP downstream respectively in pEGFT-C1 vector. We found that Alu sequences decreased the amount of GFP transcription, the percentage of GFP positive cells and the accessibility to DNase I in length-dependent manner. Inserting Alu caused the production of higher-molecular-mass RNA, indicating Ala sequence did not induce premature transcriptional termination. Tight packing chromatins keep silent and resist to DNase I digestion, which is a general phenomenon. We suggested that head and tail tandem Ala sequences suppressed GFP expression in length dependent manner by triggering chromatin packing.

• 出版日期2009-6
• 单位河北医科大学