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Genome-Wide Identification of WUSCHEL-Related Homeobox Gene Family and their Expression Analysis During Somatic Embryogenesis in Oil Palm (Elaeis guineensis)


WUSCHEL-related homeobox (WOX) genes have been shown to play important roles in the regulation of gene transcription involved in the early phases of embryogenesis. In this study, a total of 15 EgWOXs were identified from the oil palm genome and their physicochemical properties were analyzed. Phylogenetic analysis divided 15 EgWOXs into three different clades i.e. modern, ancient, and intermediate. EgWOXs contain ten conserved motifs and two conserved domains. Further, cis-acting elements analysis identified the presence of light, stress, and phytohormone responsive elements in the promoter regions of EgWOXs. RNA-seq analysis of EgWOX genes in different embryogenesis stages of oil palm embryogenic callus (EC), non-embryogenic callus (NEC), and somatic embryo (SE), indicated the significant expression of EgWOXs in EC and SE stages. Real-time PCR analysis results showed the significant expression of EgWOX2, EgWOX7, EgWOX8, EgWOX9, and EgWOX12 genes in somatic embryogenesis stage, indicating their roles in regulating oil palm somatic embryogenesis.

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Data Availability

Raw reads of RNA-seq have been uploaded in Sequence Read Archive (SRA) database (BioProject accession number: PRJNA699335).


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This work was supported by the Hainan Provincial Natural Science Foundation of China (No. 20RC738), and the Central Public-Interest Scientific Institution Basal Research Fund for the Chinese Academy of Tropical Agricultural Sciences (No. 1630152021004, 1630052021028).

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LJ conceived and supervised the project. AZ and YL conducted the experiments, RL and HC analyzed the data, LJ and RY participated in the original draft preparation. All authors reviewed, revised, and approved the manuscript.

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Correspondence to Longfei Jin.

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Authors declared no competing financial interests.

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Communicated by: Diego Mauricio M. Riaño Pachón

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Zhang, A., Li, Y., Yarra, R. et al. Genome-Wide Identification of WUSCHEL-Related Homeobox Gene Family and their Expression Analysis During Somatic Embryogenesis in Oil Palm (Elaeis guineensis). Tropical Plant Biol. 15, 55–64 (2022).

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  • WOX
  • Oil palm
  • Somatic embryogenesis
  • Gene expression