Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber

Abstract

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.

Bursaphelenchus xylophilus and B. mucronatus secretomes: a comparative proteomic analysis

“…15,000 nematodes as previously described39. A fraction of 2.0 μg was used as starting material for cDNA synthesis using the MINT cDNA synthesis kit (Evrogen), where a strategy based on SMART double stranded cDNA synthesis was applied40. cDNA was quantified by fluorescence and sequenced in a half a plate of the 454 GS-FLX Titanium system, according to the standard manufacturer’s instructions (Roche-454 Life Sciences).…”

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Mycorrhization of Fagaceae Forests Within Mediterranean Ecosystems

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Transcriptome Analysis of a Female-sterile Mutant (fsm) in Chinese Cabbage (Brassica campestris ssp. pekinensis)

“…The previous studies indicated that the genes involved in the hormone signaling may play important roles in plant sex determination (Chandler, 2011). In recent years, several different transcriptome analyses showed that numerous hormone-related genes were differently expressed between different flower types, which further indicated hormones had roles in the sexual differentiation and development of floral organ (Wu et al, 2010; Ramos et al, 2014; Rocheta et al, 2014; Sobral et al, 2016). For example, auxin enjoyed a critically regulatory function in the process of floral growth and development in plants (Aloni et al, 2006; Cheng and Zhao, 2007).…”