Robinson Kathryn M, Delhomme Nicolas, Mähler Niklas, Schiffthaler Bastian, Onskog Jenny, Albrectsen Benedicte R, Ingvarsson Pär K, Hvidsten Torgeir R, Jansson Stefan, Street Nathaniel R
Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, Umeå, 901 87, Sweden.
BMC Plant Biol. 2014 Oct 16;14:276. doi: 10.1186/s12870-014-0276-5.
Evolutionary theory suggests that males and females may evolve sexually dimorphic phenotypic and biochemical traits concordant with each sex having different optimal strategies of resource investment to maximise reproductive success and fitness. Such sexual dimorphism would result in sex biased gene expression patterns in non-floral organs for autosomal genes associated with the control and development of such phenotypic traits.
We examined morphological, biochemical and herbivory traits to test for sexually dimorphic resource allocation strategies within collections of sexually mature and immature Populus tremula (European aspen) trees. In addition we profiled gene expression in mature leaves of sexually mature wild trees using whole-genome oligonucleotide microarrays and RNA-Sequencing.
We found no evidence of sexual dimorphism or differential resource investment strategies between males and females in either sexually immature or mature trees. Similarly, single-gene differential expression and machine learning approaches revealed no evidence of large-scale sex biased gene expression. However, two significantly differentially expressed genes were identified from the RNA-Seq data, one of which is a robust diagnostic marker of sex in P. tremula.
进化理论表明，雄性和雌性可能会进化出两性异形的表型和生化特征，这与每种性别拥有不同的资源投资最优策略以实现生殖成功率和适应性最大化相一致。这种两性异形会导致常染色体基因在非花器官中出现性别偏向的基因表达模式，这些基因与此类表型特征的控制和发育相关。
我们研究了形态、生化和食草动物相关性状，以测试欧洲山杨（Populus tremula）性成熟和未成熟树木群体内两性异形的资源分配策略。此外，我们使用全基因组寡核苷酸微阵列和RNA测序对性成熟野生树木成熟叶片中的基因表达进行了分析。
我们没有发现性未成熟或成熟树木中雄性和雌性之间存在两性异形或差异资源投资策略。同样，单基因差异表达和机器学习方法也没有揭示大规模性别偏向基因表达的证据。然而，从RNA测序数据中鉴定出两个显著差异表达的基因，其中一个是欧洲山杨性别可靠的诊断标记。
