利用选择性剪切机制来构建雌性致死品系

本文梳理"利用选择性剪切机制来构建雌性致死品系"的实验历史脉络。

Release of Insects carrying a Dominant Lethal (RIDL)：显性致死基因（dominant lethal，只要有一个拷贝就会导致个体死亡即杂合致死。
tTAV：（抑制四环素转录激活因子突变），能够引起更多的tTAV突变，使得蚊子基因表达变成一个致命循环。这种蛋白质能阻塞昆虫细胞内的细胞器活动，使其他基因无法激活，从而导致昆虫死亡。

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四环素系统概念的提出：
Gong, P., Epton, M.J., Fu, G., Scaife, S., Hiscox, A., Condon, K.C., Condon, G.C., Morrison, N.I., Kelly, D.W., Dafa'alla, T., et al. (2005) A dominant lethal genetic system for autocidal control of the Mediterranean fruitfly. Nat Biotechnol 23:453-456.

1. 2007首次提出

Female-specific insect lethality engineered using alternative splicing
Nat Biotechnol， 2007，Luke Alphey

存在问题：过去的SIT策略，需要大规模饲喂昆虫，雌雄并存，而实验只需要雄虫，雄虫不育需要采用辐照，降低生存适合度和交配竞争力。

解决办法：

The release generation would be reared under restrictive conditions (without the repressor), killing the females and providing a male-only population for release. These released males would mate with wild females, and their female progeny, lacking the repressor chemical, would die. This would reduce the reproductive capacity of the population, thereby potentially controlling it.

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The tra coding region is interrupted by additional exons in males; only females produce a splice variant encoding functional Tra protein. We have exploited this female-specific excision of a cassette exon to prevent expression of an engineered protein in males, thereby making its expression female-specific.
将雌雄选择性剪切的一部分intron插入到X基因序列中，如果在雌性中，选择剪切掉这部分intron，会产生有功能的X蛋白。

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The tTAV expression cassette acts by a positive feedback mechanism to induce lethality, but here its expression and therefore lethality is limited to females by a Cctraderived alternative splicing system.

2. 2010应用于埃及伊蚊

Female-specific flightless phenotype for mosquito control
Proc Natl Acad Sci U S A，2010，Luke Alphey

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3. 2011应用于埃及伊蚊

Genetic elimination of dengue vector mosquitoes.
PNAS，2011，Black, W.C.t.
have a repressible female-specific flightless phenotype.
种群实验数据为主

4. 2012应用于实蝇科昆虫

Control of the olive fruit fly using genetics-enhanced sterile insect technique.
BMC Biol，2012，Luke Alphey
应用于Bactrocera oleae橄榄果实蝇

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Only females produce the F1 splice variant, corresponding to the reconstitution of the tTAV open reading frame and leading to production of functional tTAV.

5. 2013应用于鳞翅目害虫

Engineered female-specific lethality for control of pest Lepidoptera.
ACS Synth Biol，2013，Luke Alphey

应用于Pectinophora gossypiella棉红铃虫和Plutella xylostella小菜蛾

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优化了选择剪切的机制（OX4319），片段包含了dsx基因，在3号外显子上插入了tTAV，并且tetO操作子由21个重复减少到7个。
所建立的品系中，并不是所有的品系在抗生素存在时雌性致死都被抑制，原因是：
This variability between strains is likely a result of transgene position effect.

6. 2013应用于家蚕

Transgene-based, female-specific lethality system for genetic sexing of the silkworm, Bombyx mori.
Proc Natl Acad Sci U S A，2013 ，Yongping Huang

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