Genome-Wide Identification and Characterization of lncRNAs in sunflower endosperm

Abstract

Background: Long non-coding RNAs (lncRNAs), as important regulators, play important roles in plant growth and development. The expression and epigenetic regulation of lncRNAs remain uncharacterized generally in plant seeds, especially in the transient endosperm of the dicotyledons. Results: In this study, we identified 11,840 candidate lncRNAs in 12 day-after-pollination sunflower endosperm by analyzing RNA-seq data. These lncRNAs were evenly distributed in all chromosomes and had specific features that were distinct from mRNAs including tissue-specificity expression, shorter and fewer exons. By GO analysis of protein coding genes showing strong correlation with the lncRNAs, we revealed that these lncRNAs potential function in many biological processes of seed development. Additionally, genome-wide DNA methylation analyses revealed that the level of DNA methylation at the transcription start sites was negatively correlated with gene expression levels in lncRNAs. Finally, 36 imprinted lncRNAs were identified including 32 maternally expressed lncRNAs and four paternally expressed lncRNAs. In CG and CHG context, DNA methylation levels of imprinted lncRNAs in the upstream and gene body regions were slightly lower in the endosperm than that in embryo tissues, which indicated that the maternal demethylation potentially induce the paternally bias expression of imprinted lncRNAs in sunflower endosperm. Conclusion: Our findings not only identified and characterized lncRNAs on a genome-wide scale in the development of sunflower endosperm, but also provide novel insights into the parental effects and epigenetic regulation of lncRNAs in dicotyledonous seeds.

Estudio y evaluación de prestaciones estáticas y dinámicas de los integradores generalizados de segundo orden en las estructuras de control de inversores fotovoltaicos de dos etapas con conexión a red.

“…____ Figura 47: v DC (s)/i LfRef (s); P=230W; C DC =50μF,500μF ; t∈ [1,2,3,4,5]ms. _________ Figura 48: Ganancia de lazo Tv DC (s) con regulador Gv DC (s) (90) Azul: P∈ [30,80,130,180,230]W; C DC =500μF; t∈[0, 1,2,3,4,5]ms. Rojo: t=0ms.…”

“…Rojo: P=230W. _______ Figura 50: Respuesta en lazo cerrado v DC (s)⁄v DCRef (s)=Tv DC_CL (s) con regulador Gv DC (s) (90) Azul: P∈ [30,80,130,180,230]W; C DC =500μF; t∈[0, 1,2,3,4,5]ms. Rojo: t=0ms.…”

“…xxvii Figura 51: Respuesta en lazo cerrado v DC (s)⁄v DCRef (s)=Tv DC_CL (s) con regulador Gv DC (s) (90) Azul: P∈ [30,80,130,180,230]W; C DC =500μF; t∈[0, 1,2,3,4,5]ms. Rojo: P=230W.…”

“…Esta frecuencia se sitúa aproximadamente una década por encima del polo inestable (86) y una década por debajo de la frecuencia (F RDC ) del rizado de la DC-Link (V DC_R ). La función de transferencia del regulador Gv DC (s) para el inversor con la DC-Link de 500µF se muestra en (90).…”

“…En [90] se emplea un filtro Notch para aumentar la dinámica del control de tensión de la DC-Link, en un inversor de dos etapas sin conexión a la red eléctrica, con el objetivo de evitar que se acople la componente V DC_R al resto del sistema.…”