Xue Bingye, Rooney Alejandro P, Kajikawa Masaki, Okada Norihiro, Roelofs Wendell L
Department of Entomology, New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456, USA.
Proc Natl Acad Sci U S A. 2007 Mar 13;104(11):4467-72. doi: 10.1073/pnas.0700422104. Epub 2007 Mar 5.
The biosynthesis of female moth sex pheromone blends is controlled by a number of different enzymes, many of which are encoded by members of multigene families. One such multigene family, the acyl-CoA desaturases, is composed of certain genes that function as key players in moth sex pheromone biosynthesis. Although much is known regarding the function of some of these genes, very little is known regarding how novel genes have evolved within this family and how this might impact the establishment of new sex pheromone blends within a species. We have discovered that several cryptic Delta11 and Delta14 desaturase genes exist in the genomes of the European and Asian corn borers (Ostrinia nubilalis and Ostrinia furnacalis, respectively). Furthermore, an entirely novel class of desaturase gene has arisen in the Ostrinia lineage and is derived from duplication of the Delta11 desaturase gene and subsequent fusion with a retroposon. Interestingly, the genes have been maintained over relatively long evolutionary time periods in corn borer genomes, and they have not been recognizably pseudogenized, suggesting that they maintain functional integrity. The existence of cryptic desaturase genes in moth genomes indicates that the evolution of moth sex pheromone desaturases in general is much more complex than previously recognized.
雌蛾性信息素混合物的生物合成受多种不同酶的控制，其中许多酶由多基因家族的成员编码。这样一个多基因家族，即酰基辅酶A去饱和酶，由某些在蛾类性信息素生物合成中起关键作用的基因组成。尽管对其中一些基因的功能已了解很多，但对于该家族中新基因是如何进化的以及这可能如何影响一个物种内新的性信息素混合物的形成却知之甚少。我们发现欧洲玉米螟和亚洲玉米螟（分别为Ostrinia nubilalis和Ostrinia furnacalis）的基因组中存在几个隐秘的Delta11和Delta14去饱和酶基因。此外，在玉米螟谱系中出现了一类全新的去饱和酶基因，它源自Delta11去饱和酶基因的复制以及随后与一个反转录转座子的融合。有趣的是，这些基因在玉米螟基因组中相对较长的进化时期内得以保留，并且它们没有明显地变成假基因，这表明它们保持着功能完整性。蛾类基因组中隐秘去饱和酶基因的存在表明，一般来说蛾类性信息素去饱和酶的进化比以前认为的要复杂得多。
