Comparative profiling of microRNA expression in the developing seeds of high- and low-oil tea oil camellia (Camellia oleifera) cultivars

Abstract

KEYWORDStea oil camellia, small RNA sequencing, miRNA-mRNA function modules, lipid metabolism, seed size However, the seed yield of tea oil camellia is unstable, and the seed oil content varies greatly, which seriously restricts the sustainable development of the tea oil camellia industry in China. One 3 important strategy is the cultivation of tea oil camellia cultivars with high seed oil contents and high and stable seed yields. MicroRNAs (miRNAs) are a class of endogenous noncoding small RNAs with lengths of approximately 20-25 nucleotides and play crucial roles in mediating the posttranscriptional regulation of gene expression by targeting mRNA degradation or inhibiting target mRNA translational in eukaryotes. Studies have confirmed the key roles of miRNAs in various biological and metabolic processes in plants, such as fatty acid biosynthesis [6], lipid metabolism [7], growth and development [8], responses to stresses [9], and cellular proliferation and differentiation [10]. To date, a total of 5,141 miRNA sequences have been deposited in the database miRBase [11, 12], and many conserved and novel miRNAs have been identified in soybean [13], Arabidopsis [14], Brassica napus [15], rice [16], peony [17] and maize [18]. miRNAs control and influence a variety of physiological processes by regulating target genes. For example, the KAS and KAR genes targeted by miR159 and miR156, respectively, are important for lipid biosynthesis [19]. The FAD2 gene targeted by miR159b and miR5026 regulates and influences fatty acid biosynthesis [13, 20]. miR160 plays highly important roles in multiple aspects of shoot and root development by modulating ARF targeting [21]. In addition, transcription factors play important roles in regulating lipid biosynthesis [22], such as WRINKLED1 and LEAFY COTYLEDON, MYB, SPL, ARF and AP2 [23], which have been identified to be targeted by the major miRNAs [24]. Based on the high-throughput sRNA and degradome analyses of soybean seeds 15 days after flower, 55 annotated and 26 novel miRNAs, which targeted 145 genes, were identified [13]; 82% of the targeted genes were transcription factors, including the ARF, MYB, TCP, GRF and NAC families [13]. The expression level of TCPs that are targeted by miR319 controls the coordination and regulation of two sequential processes in leaf development: the negative regulation of leaf growth and positive regulation of leaf senescence in A. thaliana [25]. miR160 negatively regulates ARFs that significantly affect seed development in A. thaliana [26]. SPL10 and SPL11 are targeted by miR156 and involved in the early morphogenesis of Arabidopsis embryos [27]. MYBs targeted by miR159 are involved in seed size, and a double mutation of miR159 (miR159ab) increased MYB33 and MYB65 expression, which promoted the formation of small seeds [28]. Currently, miRNA-mediated regulatory networks controlling multiple biological and metabolic processes have been revealed via the functional analysis of some woody oil plants, such as oil palm [29], peony [17] and olive [30]. In d...

Hexakis(urea-O)iron Complex Salts as a Versatile Material Family: Overview of Their Properties and Applications

“…It is of enormous importance to use fertilizers for lotus trees to improve the roots’ quality by ensuring trace elements; however, due to the wet life environment, only slow- and controlled-release compounds such as the hexakis­(urea)­iron complexes can be used to avoid a potentially environmental pollution. − To ensure high-nutrition soils for sakura trees, transplantation of holly trees or garden seedlings, , these kinds of fertilizers were used with high efficiency. For flowers, like Camellia oleifera, − different kinds of roses, − or ornamental plants like Asparagus plumosus , or Epipremnum aureum, a comprehensive nutrition content and high utilization rate were reached with the use of these complexes.…”

“… 134 − 137 To ensure high-nutrition soils for sakura trees, 137 transplantation of holly trees 138 or garden seedlings, 136 , 139 these kinds of fertilizers were used with high efficiency. For flowers, like Camellia oleifera , 140 − 142 different kinds of roses, 143 − 145 or ornamental plants like Asparagus plumosus ( 146 , 147 ) or Epipremnum aureum , 148 a comprehensive nutrition content and high utilization rate were reached with the use of these complexes.…”

Current Flaxseed Dehulling Technology in China

“…Wang Jianhui et al [41] utilized a biological composite enzyme to remove the seed coat of lotus seeds, not only preserving the original color and flavor of the lotus seeds but also reducing production costs. Wu et al [42] studied an enzymatic method for removing the seed coat of oil-tea camellia seeds, which avoids nutritional losses in the kernels and features low consumption, environmental friendliness, and mild conditions. Overall, biological dehulling technology has the characteristics of high efficiency, mildness, and environmental friendliness.…”