Project description:To investigate the roles of sRNAs in keeping embryo dormancy or germination in Larix leptolepis, we deciphered the endogenous "sRNAome" in dormant and germinated embryos. High-throughput sequencing of the sRNA libraries showed that dormant embryos exhibited a length bias towards 24-nt, while germinated embryos showed a bias towards a 21-nt and/or 22-nt length. Both of proportions for miRNAs to the non-redundant and redundant sRNAs were higher in germinated embryos than those in dormant embryos, while the ratio of unknown sRNAs was higher in dormant embryos than in germinated embryos. The proportion of 21-nt and 22-nt sRNAs increased in germinated embryos, which might attribute to the higher expression level of miRNAs. We identified a total of 160 conserved miRNAs from 39 families, 16 novel miRNAs, and 14 plausible miRNA candidates, of which novel and non-conserved known miRNAs might be the main contributors. These findings indicate that larch and possibly other gymnosperms have complex mechanisms of gene regulation involving sRNAs and miRNAs operating transcriptionally and post-transcriptionally during embryo dormancy and germination. One embryogenic cell line of Japanese larch (Larix leptolepis), designated as D878, with a high embryo maturation capacity was used in this study. Embryogenic callus were induced from immature embryos of larch on induction medium, followed by sub-culture, and culture on ABA-containing mature medium in a dark environment at 25 2 C. After cultured 45 days in mature medium, embryogenic calli developed into mature somatic embryos. In our study, the samples were harvested at day 57, one sample was collected after mature embryos continued to stay for 12 days on ABA-containing medium, and the other one was harvested after cultured for 12 days on ABA-removing medium. All samples were snap-frozen in liquid nitrogen, and stored in liquid nitrogen until RNA extraction.
Project description:Somatic embryogenesis is an important biological process in several plant species, including sugarcane. Proteomics approaches have shown that H+ pumps are differentially regulated during somatic embryogenesis; however, the relationship between H+ flux and embryogenic competence is still unclear. This work aimed to elucidate the association between extracellular H+ flux and somatic embryo maturation in sugarcane. We performed a microsomal proteomics analysis and analyzed changes in extracellular H+ flux and H+ pump (P-H+-ATPase, V-H+-ATPase and H+-PPase) activity in embryogenic and non-embryogenic callus. A total of 657 proteins were identified, 16 of which were H+ pumps. We observed that P-H+-ATPase and H+-PPase were more abundant in embryogenic callus. Compared with non-embryogenic callus, embryogenic callus showed high H+ influx, especially at maturation day 14 as well as higher H+ pump activity, mainly P-H+-ATPase and H+-PPase activity. The H+-PPase appears to be the major H+ pump in embryogenic callus during somatic embryo formation, functioning in both vacuole acidification and PPi homeostasis. These results provide evidence for an association between higher H+ pump protein abundance and, consequently, higher H+ flux and embryogenic competence acquisition in the callus of sugarcane.
Project description:Small non-coding RNAs (sncRNAs) are emerging as key regulators of embryogenesis. To investigate the roles of sRNAs in regulating synchronism of somatic embryogenesis in Larix leptolepis, we deciphered the endogenous "sRNAome" in synchronous and desynchronous embryos. The 24-nt class sRNAs were overrepresented in both synchronous embryos and desynchronous embryos, accounting for 85.29% and 44.79%. A total of 29 miRNAs were upregulated in synchronous embryos, whereas 59 miRNAs were upregulated in desynchronous embryos. We describe the emerging theme for sncRNAs function: inhibiting the precocious expression, thus regulating the synchronism of somatic embryogenesis. These findings indicate that larch and possibly other gymnosperms have complex mechanisms of gene regulation involving sRNAs and miRNAs operating transcriptionally and post-transcriptionally during the regulation of synchronism. One embryogenic cell line of Japanese larch (Larix leptolepis), designated as D878, with a high embryo maturation capacity was used in this study. Embryogenic callus was induced from immature embryos of Japanese larch on induction medium followed by sub-culture. Calli at the proembryogenic mass III stage were cultured on maturation medium in a dark environment at 25 M-BM-1 2M-BM-0C. Samples were cultured on ABA-plus or ABA-minus maturation medium for 45 days. All samples were snap-frozen in liquid nitrogen, and stored in liquid nitrogen until RNA extraction.
Project description:Purpose: Maize somatic embryogenesis is usually required to achieve genetic transformation and represents an important alternative in plant development. Although many embryogenesis-related genes have been studied in this model, the molecular mechanisms underlying cell dedifferentiation and further plant regeneration are not completely understood. Methods: Immature embryos smRNA profiles of 15-day-after-pollination (IE) and Embryogenic Callus from one (C1), four (C4), and ten months (C10) were generated by deep sequencing, using Illumina GAIIx. The sequence reads that passed quality filters were analyzed with two methods: Bowtie 1.1.2 and ShortStack 3.4. qRT–PCR validation for selected miRNAs was performed using SYBR Green assays. Results: We used high throughput sequencing to explore the sRNA populations during maize embryogenic callus induction and established subcultures from the Mexican cultivar VS-535, Tuxpeño landrace. We detected readjustments in 24 nt and 21-22 nt sRNA populations during the embryogenic callus establishment and maintenance. miRNAs related to stress response substantially increased upon callus proliferation establishment, correlating with a reduction in some of their target levels. On the other hand, while 24 nt-long hc-siRNAs derived from transposable retroelements transiently decreased in abundance during the embryogenic callus establishment, a population of 22 nt- hc-siRNAs increased. This was accompanied by reduction in transposon expression in the established callus subcultures. Conclusions: Stress- and development-related miRNAs are highly expressed upon maize EC callus induction and during maintenance subcultures, while miRNAs involved in hormone response only transiently increase during induction. The establishment of proliferative maize embryogenic callus is accompanied by important readjustments in the length of hc-siRNAs mapping to LTR retrotransposons, and their expression regulation.
Project description:gnp07_regeneome_embryogenesis - embryogenesis col0 - Identify genes involved in somatic embryogenesis - compare embryogenic areas of a callus with undifferenciate area in the same callus
Project description:gnp07_regeneome_embryogenesis - embryogenesis ws - Identify genes involved in somatic embryogenesis - To compare embryogenic areas of a callus with undifferenciate area in the same callus
Project description:Objectives: to characterize and to better understand differences at a protein level in embryonic and non-embryogenic tissues of embryonal masses in Douglas-fir. In Europe, Douglas-fir is a major species for reforestation with increasing demand for its wood. Harvested stems provide timber of outstanding wood quality, mechanical properties and durability. Commercial Douglas-fir plantations in France are limited by the ability to produce seed from the latest breeding developments. Somatic embryogenesis is considered a promising biotechnology for large-scale clonal propagation of forest trees, due to the high multiplication rates it can provide. Moreover, embryogenic cultures are amenable to both cryogenic storage for long-term preservation of genetic resources and genetic engineering (including genome editing) for functional characterization of genes expressed during embryogenesis. In conifers, embryogenic cultures take the form of embryonal mass made up of early differentiated cells forming immature somatic embryos that proliferate via cleavage polyembryony. In Douglas-fir embryogenic lines consisting in embryonal mass have been compared to non-embryogenic callus during their proliferation. Comparison of proteomes (free-gel proteomics) of embryonal mass vs non-embryogenic callus were performed.
2019-05-17 | PXD011176 | Pride
Project description:Transcriptome Analysis of Embryogenic and Non-Embryogenic Callus of Picea mongolica