Viney Mark E, Gardner Michael P, Jackson Joseph A
School of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK.
Dev Growth Differ. 2003 Aug;45(4):389-96. doi: 10.1046/j.1440-169x.2003.00703.x.
Dauer larvae of Caenorhabditis elegans are formed when young larvae experience conditions of low food availability and high conspecific population density; non-dauer, third stage larvae are formed in conditions of plenty. This developmental response to environmental conditions is an example of phenotypic plasticity; that is, an environmentally induced change in phenotype and, as such, a manifestation of a genotype-environment interaction. Extensive variation was found in reaction norms of phenotypic plasticity of dauer formation among wild lines of C. elegans. Recombinant-inbred lines were constructed from parental lines with very different reaction norms of dauer formation. These recombinant-inbred lines had a wide range of reaction norms, of a range greater than that set by the parental lines. The natural variation in reaction norms of dauer formation in C. elegans is, presumably, an adaptation to enhance fitness under the lines' different natural prevailing conditions. The genetic basis of this variation, as well as its phenotypic consequences, are now ripe for further investigation.
秀丽隐杆线虫的 dauer 幼虫是在幼虫经历食物供应不足和同种种群密度高的条件时形成的；非 dauer 的第三阶段幼虫则是在食物充足的条件下形成的。这种对环境条件的发育反应是表型可塑性的一个例子；也就是说，这是一种由环境诱导的表型变化，因此也是基因型 - 环境相互作用的一种表现。在秀丽隐杆线虫的野生品系中，发现 dauer 形成的表型可塑性反应规范存在广泛差异。从 dauer 形成反应规范非常不同的亲本品系构建了重组自交系。这些重组自交系具有广泛的反应规范，其范围大于亲本品系所设定的范围。秀丽隐杆线虫 dauer 形成反应规范的自然变异大概是一种适应，以增强这些品系在不同自然环境条件下的适应性。这种变异的遗传基础及其表型后果，现在已具备进一步研究的条件。
