A Selection of Reliable Reference Genes for Gene Expression Analysis in the Female and Male Flowers of Salix suchowensis.

Fangwei Zhou,Tongming Yin,Yingnan Chen,Huaitong Wu

doi:10.3390/plants11050647

Abstract

Salix is a dioecious plant. Research on the molecular regulation mechanism of male and female inflorescence differentiation and development is necessary to analyze sex differentiation in the willow and the underlying mechanisms of unisexual flower development. However, at present, there are no reference genes suitable for stable expression in the process of willow inflorescence development. In this study, Salix suchowensis was used as the research material, nine candidate reference genes (α-TUB1, α-TUB2, ACT, H2A, DnaJ, CDC2, GAPDH, TIP41, β-TUB) were selected, and qRT-PCR technology was used to detect the expression of each candidate reference gene in female and male flowers at different developmental stages and using five algorithms (geNorm, Normfinder, Delta Ct, BestKeeper, and RefFinder) to comprehensively evaluate the stability of candidate reference genes. The results showed that ACT and DnaJ were stably expressed in all samples and could be used as reference genes. In addition, the reliability of the screening results was further verified via an expression pattern analysis of the CFS gene that encodes flower specific transcription factor in different samples. The stable reference genes selected in this study provide the basis for future research on the expression analysis of functional genes related to the development of male and female flowers of S. suchowensis.

Highlights

Salix is widely distributed in the northern hemisphere
> DnaJ > TIP41 > α-TUB2 > H2A > α-TUB1 > glyceraldehyde-3-phosphate dehydrogenase (GAPDH) > β-TUB > CDC2 (Table 3). These results suggested that ACT and DnaJ were the ideal reference genes
The is a dioecious tree, tree, and the differences are primarily reflected in the variation of the flower organ morphology [28,29]

Summary

Introduction

Due to its rapid growth, easy asexual reproduction, and strong environmental adaptability, it is often used as a landscaping and economic timber tree species [1–3]. The reproductive characteristics of willow are dioecious. The female willow tree has good material qualities, and its growth performance is generally better than the male plant and so the elite clones of willow trees that are selected and promoted are mainly female plants. The gender dimorphism of willow trees is mainly reflected in the differences in the flower organs [4]. After the female flower is pollinated, the capsules mature and produce catkins that are released into the air and can cause breathing difficulties in humans [5]. After the male flower matures, it produces a large amount of pollen. The pollen grains are small and light and can be spread by wind, acting as a potential allergen upon contact and inhalation in humans [6,7]

Methods

Results

Conclusion