A promoter element active in run-off transcription controls the expression of two cistrons of nad and rps genes in Nicotiana sylvestris mitochondria
A promoter element active in run-off transcription controls the expression of two cistrons of nad and rps genes in Nicotiana sylvestris mitochondria
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DOI：
10.1093/nar/24.23.4798
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发表时间：
1996-12-01
影响因子：
14.9
通讯作者：
Chetrit, P
中科院分区：
文献类型：
--
作者：
Lelandais, C;Gutierres, S;Chetrit, P
研究了两个线粒体基因簇（orf 87-nad 3-nad 1/A和orf 87-nad 3-rps 12）在欧洲烟草（Nicotianasylvestris）中的表达。通过引物延伸和核酸酶S1保护定位转录物的5'和3'末端。通过体外磷酸化和加帽实验区分加工和转录起始位点。在orf 87上游213个核苷酸处发现了存在于两个基因簇中的转录起始位点。该启动子元件与双子叶植物线粒体启动子的共有基序匹配，并启动豌豆线粒体纯化蛋白组分中的径流转录。加工位点分别鉴定为nad 3、nad 1/A和rps 12的5'。这些结果表明：（i）两个顺反子的表达仅由一个重复的启动子元件控制，和（ii）需要多个加工事件来产生单顺反子nad 3，nad 1/A和rps 12转录本。
The expression of two mitochondrial gene clusters (orf87-nad3-nad1/A and orf87-nad3-rps 12) was studied in Nicotiana sylvestris. 5' and 3' termini of transcripts were mapped by primer extension and nuclease S1 protection. Processing and transcription initiation sites were differentiated by in vitro phosphorylation and capping experiments. A transcription initiation site, present in both gene clusters, was found 213 nucleotides upstream of orf87. This promoter element matches the consensus motif for dicotyledonous mitochondrial promoters and initiates run-off transcription in a pea mitochondrial purified protein fraction, Processing sites were identified 5' of nad3, nad1/A and rps12 respectively. These results suggest that (i) the expression of the two cistrons is only controlled by one duplicated promoter element, and (ii) multiple processing events are required to produce monocistronic nad3, nad1/A and rps12 transcripts.