Dataset Information

Germination and Early Seedling Development in Quercus ilex Recalcitrant and Non-dormant Seeds: Targeted Transcriptional, Hormonal, and Sugar Analysis.

ABSTRACT: Seed germination and early seedling development have been studied in the recalcitrant species Quercus ilex using targeted transcriptional, hormonal, and sugar analysis. Embryos and seedlings were collected at eight morphologically defined developmental stages, S0-S7. A typical triphasic water uptake curve was observed throughout development, accompanied by a decrease in sucrose and an increase in glucose and fructose. Low levels of abscisic acid (ABA) and high levels of gibberellins (GAs) were observed in mature seeds. Post-germination, indole-3-acetic acid (IAA), increased, whereas GA remained high, a pattern commonly observed during growth and development. The abundance of transcripts from ABA-related genes was positively correlated with the changes in the content of the phytohormone. Transcripts of the drought-related genes Dhn3 and GolS were more abundant at S0, then decreased in parallel with increasing water content. Transcripts for Gapdh, and Nadh6 were abundant at S0, supporting the occurrence of an active metabolism in recalcitrant seeds at the time of shedding. The importance of ROS during germination is manifest in the high transcript levels for Sod and Gst, found in mature seeds. The results presented herein help distinguish recalcitrant (e.g., Q. ilex) seeds from their orthodox counterparts. Our results indicate that recalcitrance is established during seed development but not manifest until germination (S1-S3). Post-germination the patterns are quite similar for both orthodox and recalcitrant seeds.

SUBMITTER: Romero-Rodriguez MC

PROVIDER: S-EPMC6204751 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Germination and Early Seedling Development in <i>Quercus ilex</i> Recalcitrant and Non-dormant Seeds: Targeted Transcriptional, Hormonal, and Sugar Analysis.

Romero-Rodríguez M Cristina MC Archidona-Yuste Antonio A Abril Nieves N Gil-Serrano Antonio M AM Meijón Mónica M Jorrín-Novo Jesús V JV

Frontiers in plant science 20181022

Seed germination and early seedling development have been studied in the recalcitrant species <i>Quercus ilex</i> using targeted transcriptional, hormonal, and sugar analysis. Embryos and seedlings were collected at eight morphologically defined developmental stages, S0-S7. A typical triphasic water uptake curve was observed throughout development, accompanied by a decrease in sucrose and an increase in glucose and fructose. Low levels of abscisic acid (ABA) and high levels of gibberellins (GAs) ...[more]

PMID: 30405659

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Project description:Proteases and protease inhibitors have been analyzed in the non-orthodox Quercus ilex forest tree by using in silico and wet approaches. The in silico analysis showed that the species-specific transcriptome database included 2240 and 97 transcripts annotated as, respectively, proteases and protease inhibitors, with members of the different families according to the MEROPS protease database (http://www.merops.ac.uk) classification, mostly of serine- and metallo-type. Data for Q. ilex are compared with those previously published for other Quercus species, namely, Q. suber, Q. lobata, and Q. robur. A second approach was performed to assess the evolution of proteases and protease inhibitors along with seed germination in cotyledon and embryo tissues by determining changes at proteomics and activity levels, the last by mean of in vitro and in gel assays. Shotgun (LC-MSMS) analysis of acorn embryos and cotyledons of three developmental stages (NV, non-viable; T1, mature; and T3 germinated) allowed the identification of a total of 177 proteases and 12 protease inhibitors. In vitro protease activity was determined by using azocasein as substrate; the total activity was higher in cotyledons than embryos, showing the latter significant differences throughout germination. Gel protease activity assays showed common and differential bands between tissues and developmental stages. Shotgun analysis of 10 differential activity bands supported the results obtained from the whole proteome analysis, with some proteins highly represented in the same tissues and stages by both strategies. In overall, the combination of shotgun proteomics and protease activity approaches allowed the identification of tissue-specific (such as cysteine protease inhibitors), and stage-specific proteins (such as those related to storage proteins mobilization), with others being present in all the analyzed organs. Some of the proteases and protease inhibitors differentially identified between tissues and stages in this study could be used as indicators of seed quality and viability.

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Dataset Information

Germination and Early Seedling Development in Quercus ilex Recalcitrant and Non-dormant Seeds: Targeted Transcriptional, Hormonal, and Sugar Analysis.

Publications

Germination and Early Seedling Development in <i>Quercus ilex</i> Recalcitrant and Non-dormant Seeds: Targeted Transcriptional, Hormonal, and Sugar Analysis.

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