Rocheta Margarida, Sobral Rómulo, Magalhães Joana, Amorim Maria I, Ribeiro Teresa, Pinheiro Miguel, Egas Conceição, Morais-Cecílio Leonor, Costa Maria M R
Departamento de Recursos Naturais Ambiente e Território, Instituto Superior de Agronomia, Universidade de Lisboa Lisboa, Portugal.
Centre for Biodiversity, Functional & Integrative Genomics, Plant Functional Biology Centre, University of Minho Braga, Portugal.
Front Plant Sci. 2014 Nov 6;5:599. doi: 10.3389/fpls.2014.00599. eCollection 2014.
Monoecious species provide a comprehensive system to study the developmental programs underlying the establishment of female and male organs in unisexual flowers. However, molecular resources for most monoecious non-model species are limited, hampering our ability to study the molecular mechanisms involved in flower development of these species. The objective of this study was to identify differentially expressed genes during the development of male and female flowers of the monoecious species Quercus suber, an economically important Mediterranean tree. Total RNA was extracted from different developmental stages of Q. suber flowers. Non-normalized cDNA libraries of male and female flowers were generated using 454 pyrosequencing technology producing a total of 962,172 high-quality reads with an average length of 264 nucleotides. The assembly of the reads resulted in 14,488 contigs for female libraries and 10,438 contigs for male libraries. Comparative analysis of the transcriptomes revealed genes differentially expressed in early and late stages of development of female and male flowers, some of which have been shown to be involved in pollen development, in ovule formation and in flower development of other species with a monoecious, dioecious, or hermaphroditic sexual system. Moreover, we found differentially expressed genes that have not yet been characterized and others that have not been previously shown to be implicated in flower development. This transcriptomic analysis constitutes a major step toward the characterization of the molecular mechanisms involved in flower development in a monoecious tree with a potential contribution toward the knowledge of conserved developmental mechanisms in other species.
雌雄同株物种提供了一个全面的系统，用于研究单性花中雌蕊和雄蕊器官形成的发育程序。然而，大多数雌雄同株非模式物种的分子资源有限，这阻碍了我们对这些物种花发育所涉及分子机制的研究。本研究的目的是鉴定经济上重要的地中海树木——栓皮栎雌雄同株物种中雄花和雌花发育过程中的差异表达基因。从栓皮栎花的不同发育阶段提取总RNA。利用454焦磷酸测序技术构建了雄花和雌花的非标准化cDNA文库，共产生962,172条高质量 reads，平均长度为264个核苷酸。reads的组装产生了雌花文库的14,488个重叠群和雄花文库的10,438个重叠群。转录组的比较分析揭示了在雌花和雄花发育早期和晚期差异表达的基因，其中一些基因已被证明参与了花粉发育、胚珠形成以及其他具有雌雄同株、雌雄异株或雌雄同体性别系统物种的花发育。此外，我们还发现了尚未被表征的差异表达基因以及其他先前未显示与花发育有关的基因。这种转录组分析是朝着表征雌雄同株树木花发育所涉及分子机制迈出的重要一步，可能有助于了解其他物种中保守的发育机制。
