Journal article

Publication year: 2008

Pages: 1436-1452

Journal: Plant Physiology

Volume number: 148

Issue number: 3

ISSN: 0032-0889

eISSN: 1532-2548

DOI Link: https://doi.org/10.1104/pp.108.127001

Publisher: Oxford University Press

Abstract: 
Nucellar projection (NP) and endosperm transfer cells (ETC) are essential tissues in growing barley (Hordeum vulgare) grains, responsible for nutrient transfer from maternal to filial tissues, endosperm/embryo nutrition, and grain development. A laser microdissection pressure catapulting-based transcriptome analysis was established to study NP and ETC separately using a barley 12K macroarray. A major challenge was to isolate high-quality mRNA from preembedded, fixed tissue while maintaining tissue integrity. We show that probes generated from fixed and embedded tissue sections represent largely the transcriptome (>70%) of nonchemically treated and nonamplified references. In NP, the top-down gradient of cellular differentiation is reflected by the expression of C3HC4-type ubiquitin ligases and different histone genes, cell wall biosynthesis and expansin/extensin genes, as well as genes involved in programmed cell death-related proteolysis coupled to nitrogen remobilization, indicating distinct areas simultaneously undergoing mitosis, cell elongation, and disintegration. Activated gene expression related to gibberellin synthesis and function suggests a regulatory role for gibberellins in establishment of the differentiation gradient. Upregulation of plasmalemma-intrinsic protein and tonoplast-intrinsic protein genes indicates involvement in nutrient transfer and/or unloading. In ETC, AP2/EREBP-like transcription factors and ethylene functions are transcriptionally activated, a response possibly coupled to activated defense mechanisms. Transcriptional activation of nucleotide sugar metabolism may be attributed to ascorbate synthesis and/or cell wall biosynthesis. These processes are potentially controlled by trehalose-6-P synthase/phosphatase, as suggested by expression of their respective genes. Up-regulation of amino acid permeases in ETC indicates important roles in active nutrient uptake from the apoplastic space into the endosperm.

Harvard Citation style: Thiel, J., Weier, D., Sreenivasulu, N., Strickert, M., Weichert, N., Melzer, M., et al. (2008) Different Hormonal Regulation of Cellular Differentiation and Function in Nucellar Projection and Endosperm Transfer Cells: A Microdissection-Based Transcriptome Study of Young Barley Grains, Plant Physiology, 148(3), pp. 1436-1452. https://doi.org/10.1104/pp.108.127001

APA Citation style: Thiel, J., Weier, D., Sreenivasulu, N., Strickert, M., Weichert, N., Melzer, M., Czauderna, T., Wobus, U., Weber, H., & Weschke, W. (2008). Different Hormonal Regulation of Cellular Differentiation and Function in Nucellar Projection and Endosperm Transfer Cells: A Microdissection-Based Transcriptome Study of Young Barley Grains. Plant Physiology. 148(3), 1436-1452. https://doi.org/10.1104/pp.108.127001