Mutator transposon insertions within maize genes often provide a novel outward reading promoter
Mutator transposon insertions within maize genes often provide a novel outward reading promoter
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DOI：
10.1093/genetics/iyad171
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发表时间：
2023-11-01
期刊：
影响因子：
3.3
通讯作者：
Springer，Nathan M.
中科院分区：
文献类型：
--
作者：
Ellison，Erika L.;Zhou，Peng;Springer，Nathan M.
高度活跃的mutator (Mu) DNA转座子家族已被广泛用于玉米的正向和反向遗传。有一些基于mu活性导致条件表型效应的mu抑制等位基因的例子。这些emu抑制突变的表型在mu活性遗传背景下观察到，但在muactivity丢失时则不存在。对于一些emu抑制性等位基因，表型抑制可能是由mu1中的外读启动子引起的，该启动子仅在自主基因沉默或丢失时才有活性。我们从UniformMu群体中分离出35个代表24个不同基因插入的muallele。这些突变等位基因大多是由于基因编码序列内的插入，但也包括一些5 ' UTR和内含子插入。RNA-seq和de novo转录本组装被用来记录33个这些插入等位基因产生的转录本。对于33个等位基因中的20个，有证据表明转录本在通过基因读取的musequence中启动。这种外读启动子活性在多种类型的muelement中检测到，并且不依赖于mu的取向。对mu启动转录本的表达分析显示，mu启动子通常提供与野生型基因相似的基因表达水平和模式。这些结果表明，该启动子可能代表了一个最小的启动子，可以响应基因调控元件。这项研究的发现对使用UniformMu群体的玉米研究人员具有启示意义，并且更广泛地强调了转座子与宿主共存的策略。
The highly active family ofMutator(Mu) DNA transposons has been widely used for forward and reverse genetics in maize. There are examples ofMu-suppressible alleles that result in conditional phenotypic effects based on the activity ofMu. Phenotypes from theseMu-suppressible mutations are observed inMu-active genetic backgrounds, but absent whenMuactivity is lost. For someMu-suppressible alleles, phenotypic suppression likely results from an outward-reading promoter withinMuthat is only active when the autonomousMuelement is silenced or lost. We isolated 35Mualleles from the UniformMu population that represent insertions in 24 different genes. Most of these mutant alleles are due to insertions within gene coding sequences, but several 5′ UTR and intron insertions were included. RNA-seq and de novo transcript assembly were utilized to document the transcripts produced from 33 of theseMuinsertion alleles. For 20 of the 33 alleles, there was evidence of transcripts initiating within theMusequence reading through the gene. This outward-reading promoter activity was detected in multiple types ofMuelements and does not depend on the orientation ofMu. Expression analyses ofMu-initiated transcripts revealed theMupromoter often provides gene expression levels and patterns that are similar to the wild-type gene. These results suggest theMupromoter may represent a minimal promoter that can respond to genecis-regulatory elements. Findings from this study have implications for maize researchers using the UniformMu population, and more broadly highlight a strategy for transposons to co-exist with their host.