A nuclear mutation that post-transcriptionally blocks accumulation of a yeast mitochondrial gene product can be suppressed by a mitochondrial gene rearrangement.
A nuclear mutation that post-transcriptionally blocks accumulation of a yeast mitochondrial gene product can be suppressed by a mitochondrial gene rearrangement.
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转录后阻止酵母线粒体基因产物积累的核突变可以通过线粒体基因重排来抑制。
DOI：
10.1016/0022-2836(84)90178-5
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发表时间：
1984
影响因子：
5.6
通讯作者：
Fox,TD
中科院分区：
文献类型：
--
作者：
Müller,PP;Reif,MK;Zonghou,S;Sengstag,C;Mason,TL;Fox,TD
核琥珀突变，pet 494 -1，专门阻止线粒体geneox 2，细胞色素氧化酶亚基III的产物的积累。pet 494 -1突变并不阻止线粒体基因的转录，因为RNA-凝胶印迹杂交显示突变细胞含有正常量的anoxi 2转录物，其大小与野生型无区别。分离出部分抑制核突变的线粒体突变。这个“线粒体回复突变体”表现得好像它含有两种不同的线粒体DNA：一个是+，另一个是-。抑制突变携带在线粒体DNA上，显然是oxi 2和另一个线粒体基因oxi 3之间的基因融合的结果。该基因重排将foxi 2的正常5′-非翻译序列替换为foxi 3第二内含子的开放阅读框的一部分。在线粒体回复突变体中检测到重排基因的新转录物，其包含位于p23上游的oxi 3序列。该菌株积累了一种细胞色素氧化酶亚基III的遗传变异形式，可能是从一个新的起始密码子翻译而来。这些数据与PET 494蛋白在线粒体内特异性促进theoxi 2信使RNA翻译的模型一致。
The nuclear amber mutation,pet494-1, specifically blocks the accumulation of the product of the mitochondrial geneoxi2, cytochrome oxidase subunit III. Thepet494-1 mutation does not prevent transcription of the mitochondrial gene since RNA-gel blot hybridizations showed that mutant cells contain normal amounts of anoxi2transcript, indistinguishable in size from wild-type. A mitochondrial mutation that partially suppresses the nuclear mutation was isolated. The “mitochondrial revertant” behaved as though it contained two different mitochondrial DNAs: onerho+, the otherrho−. The suppressor mutation is carried on therho−mitochondrial DNA and is apparently the result of a gene fusion betweenoxi2and another mitochondrial gene.oxi3. This gene rearrangement replaced the normal 5′-non-translated sequence ofoxi2with a portion of the open reading frame of the second intron ofoxi3. Novel transcripts of the rearranged gene, containingoxi3sequences upstream fromoxi2were detected in the mitochondrial revertant. The strain accumulated an electrophoretically variant form of cytochrome oxidase subunit III, probably translated from a new initiation codon. The data are consistent with models in which thePET494protein acts within the mitochondria to specifically promote the translation of theoxi2messenger RNA.