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Transcriptomic changes during cell wall biogenesis and modifications during xylogenesis in stems and pioneer roots of Populus trichocarpa

ABSTRACT: We studied the changes that occur in gene transcription and the biosynthesis of cell-wall-related compounds during xylogenesis in Populus trichocarpa pioneer roots and stems. Transcriptional profiling was conducted with the use of microarrays to identify genes involved in xylem formation. Pioneer roots were examined in segments corresponding to their developmental stage: apical meristem (PR1), primary development (PR2), and secondary development (PR3). Comparative segments were used to analyze xylogenesis in stems: apical meristem with primary development (PS1), secondary development (PS2), and isolated secondary xylem (PS3). Results indicated that only approximately 10% of the genes that were identified to be differentially expressed during xylogenesis were common to both pioneer roots and stems. Despite the dissimilarity in gene expression, however, many fundamental mechanisms were similar, e.g. the pattern of expression of genes involved in the biosynthesis of cell wall proteins, polysaccharides and lignins. While hemicellulose degradation was typical for stems, possibly due to the intensive level of cell wall lignification. Our study is the first to conduct a comprehensive analysis, at the structural and molecular level, of xylogenesis, and clearly reveals the great complexity of molecular mechanisms underlying cell wall formation and modification during xylogenesis.

ORGANISM(S): Populus trichocarpa Populus sp.

PROVIDER: GSE126842 | GEO | 2019/10/14

REPOSITORIES: GEO

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Transcriptomic changes during cell wall biogenesis and modifications during xylogenesis in stems and pioneer roots of Populus trichocarpa

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