Project description:Bud dormancy is a crucial stage in perennial trees and allows survival over winter and optimal subsequent flowering and fruit production. Environmental conditions, and in particular temperature, have been shown to influence bud dormancy. Recent work highlighted some physiological and molecular events happening during bud dormancy in trees. However, we still lack a global understanding of transcriptional changes happening during bud dormancy. We conducted a fine tune temporal transcriptomic analysis of sweet cherry (Prunus avium L.) flower buds from bud organogenesis until the end of bud dormancy using next-generation sequencing. We observe that buds in organogenesis, paradormancy, endodormancy and ecodormancy are characterised by distinct transcriptional states, and associated with different pathways. We further identified that endodormancy can be separated in two phases based on its transcriptomic state: early and late endodormancy. We also found that transcriptional profiles of just 7 genes are enough to predict the main cherry tree flower buds dormancy stages. Our results indicate that transcriptional changes happening during dormancy are robust and conserved between different sweet cherry cultivars. Our work also sets the stage for the development of a fast and cost effective diagnostic tool to molecularly define the flower bud stage in cherry trees.
Project description:Current knowledge of the molecular regulation of the blastocyst implantation event has been largely derived from studies in the mouse that requires ovarian estrogen for initiation of the implantation event. However, there are species such as the hamster, guinea pig, pig, horse, rhesus monkey and perhaps the human where the blastocyst implantation event initiates only in the progesterone-primed uterus. Despite this fundamental difference in the requirement of ovarian hormones in initiating blastocyst implantation among species, efforts to identify gene networks relevant for the blastocyst implantation event in progesteroneM-bM-^@M-^Sdependent species are limited. In this study, cDNA prepared from RNAs of day 5 blastocyst implantation and interimplantation sites were hybridized with mouse and human oligonucleotide microarray platforms to discern the transcriptional networks underlying the regulation of blastocyst implantation in hamsters. Compared with the inter-implantation site, blastocyst implantation sites showed upregulation and downregulation of a sizable number of genes by both cross-species arrays.The merit of the cross-species hybridization and reliability of the identified up- and down-regulated genes at the implantation sites were validated by detecting differential expression of a few randomly selected genes from both arrays by real-time PCR. Function gene ontology and pathway analysis revealed that differentially expressed genes are associated with several biological events and molecular pathways that are likely to be taking place at the blastocyst implantation site. This is the first study that identified the differential gene expression profile at the blastocyst implantation site of the hamsters, and revealed molecular pathways that are possibly associated with the progesterone-dependent blastocyst implantation process. We used microarrays to detail the expression differences in hamster implantation and interimplantation sites. Total RNAs were prepared from the hamster day 5 blastocyst implantation and interimplantation sites. Three sets of RNAs were isolated from three different animals and were subjected to microarray analysis using Affymetrix mouse and human array platforms.
Project description:Current knowledge of the molecular regulation of the blastocyst implantation event has been largely derived from studies in the mouse that requires ovarian estrogen for initiation of the implantation event. However, there are species such as the hamster, guinea pig, pig, horse, rhesus monkey and perhaps the human where the blastocyst implantation event initiates only in the progesterone-primed uterus. Despite this fundamental difference in the requirement of ovarian hormones in initiating blastocyst implantation among species, efforts to identify gene networks relevant for the blastocyst implantation event in progesteroneM-bM-^@M-^Sdependent species are limited. In this study, cDNA prepared from RNAs of day 5 blastocyst implantation and interimplantation sites were hybridized with mouse and human oligonucleotide microarray platforms to discern the transcriptional networks underlying the regulation of blastocyst implantation in hamsters. Compared with the inter-implantation site, blastocyst implantation sites showed upregulation and downregulation of a sizable number of genes by both cross-species arrays.The merit of the cross-species hybridization and reliability of the identified up- and down-regulated genes at the implantation sites were validated by detecting differential expression of a few randomly selected genes from both arrays by real-time PCR. Function gene ontology and pathway analysis revealed that differentially expressed genes are associated with several biological events and molecular pathways that are likely to be taking place at the blastocyst implantation site. This is the first study that identified the differential gene expression profile at the blastocyst implantation site of the hamsters, and revealed molecular pathways that are possibly associated with the progesterone-dependent blastocyst implantation process. We used microarrays to detail the expression differences in hamster implantation and interimplantation sites. Total RNAs were prepared from the hamster day 5 blastocyst implantation and interimplantation sites. Three sets of RNAs were isolated from three different animals and were subjected to microarray analysis using Affymetrix mouse and human array platforms.
Project description:Pre-implantation embryo development is an intricate and precisely regulated process orchestrated by maternally inherited proteins and newly synthesized proteins following zygotic genome activation. Although genomic and transcriptomic studies have enriched our understanding of genetic programs underlying this process, the protein expression landscape remains unexplored. Using quantitative mass spectrometry, we identified nearly 5000 proteins from 8000 mouse embryos of each stage (zygote, 2-cell, 4-cell, 8-cell, morula, blastocyst). We found that protein expression of zygote, morula and blastocyst show apparent difference from 2- to 8-cell embryos. Analysis of protein phosphorylation led to extraction of critical kinases and signal transduction pathways. We identified novel factors and proved that they play important roles in early embryo development. Combined analysis of transcriptomic and proteomic data reveals coordinated control of RNA degradation, transcription and translation, and identifies novel exon junction-derived peptides. Our study provides an invaluable resource for further mechanistic studies and suggests novel players governing pre-implantation embryo development.
Project description:Global transcriptome analysis identifies regulated transcripts and pathways activated during oogenesis and early embryogenesis in Atlantic cod
Project description:Current knowledge of the molecular regulation of the blastocyst implantation event has been largely derived from studies in the mouse that requires ovarian estrogen for initiation of the implantation event. However, there are species such as the hamster, guinea pig, pig, horse, rhesus monkey and perhaps the human where the blastocyst implantation event initiates only in the progesterone-primed uterus. Despite this fundamental difference in the requirement of ovarian hormones in initiating blastocyst implantation among species, efforts to identify gene networks relevant for the blastocyst implantation event in progesterone–dependent species are limited. In this study, cDNA prepared from RNAs of day 5 blastocyst implantation and interimplantation sites were hybridized with mouse and human oligonucleotide microarray platforms to discern the transcriptional networks underlying the regulation of blastocyst implantation in hamsters. Compared with the inter-implantation site, blastocyst implantation sites showed upregulation and downregulation of a sizable number of genes by both cross-species arrays.The merit of the cross-species hybridization and reliability of the identified up- and down-regulated genes at the implantation sites were validated by detecting differential expression of a few randomly selected genes from both arrays by real-time PCR. Function gene ontology and pathway analysis revealed that differentially expressed genes are associated with several biological events and molecular pathways that are likely to be taking place at the blastocyst implantation site. This is the first study that identified the differential gene expression profile at the blastocyst implantation site of the hamsters, and revealed molecular pathways that are possibly associated with the progesterone-dependent blastocyst implantation process. We used microarrays to detail the expression differences in hamster implantation and interimplantation sites.
Project description:Current knowledge of the molecular regulation of the blastocyst implantation event has been largely derived from studies in the mouse that requires ovarian estrogen for initiation of the implantation event. However, there are species such as the hamster, guinea pig, pig, horse, rhesus monkey and perhaps the human where the blastocyst implantation event initiates only in the progesterone-primed uterus. Despite this fundamental difference in the requirement of ovarian hormones in initiating blastocyst implantation among species, efforts to identify gene networks relevant for the blastocyst implantation event in progesterone–dependent species are limited. In this study, cDNA prepared from RNAs of day 5 blastocyst implantation and interimplantation sites were hybridized with mouse and human oligonucleotide microarray platforms to discern the transcriptional networks underlying the regulation of blastocyst implantation in hamsters. Compared with the inter-implantation site, blastocyst implantation sites showed upregulation and downregulation of a sizable number of genes by both cross-species arrays.The merit of the cross-species hybridization and reliability of the identified up- and down-regulated genes at the implantation sites were validated by detecting differential expression of a few randomly selected genes from both arrays by real-time PCR. Function gene ontology and pathway analysis revealed that differentially expressed genes are associated with several biological events and molecular pathways that are likely to be taking place at the blastocyst implantation site. This is the first study that identified the differential gene expression profile at the blastocyst implantation site of the hamsters, and revealed molecular pathways that are possibly associated with the progesterone-dependent blastocyst implantation process. We used microarrays to detail the expression differences in hamster implantation and interimplantation sites.
Project description:TF1a AML cell line was selected for in vitro modelling of dormancy in AML. TF1-a were subjected to AML-niche-mimicking in vitro conditioning by culture with TGFB1 and the mTOR inhibitor rapamycin. Also TF1a cells were in vitro cultured with prolonged sublethal doses of Etoposide. The molecular signature of untreated, dormancy induced and genotoxicity-surviving TF1a cells were investigated using global human genome GEP to identify drivers of dormancy in different conditioning scenarios in comparison to untreated counterparts.
Project description:Studies using low-resolution methods to assess gene expression during preimplantation mouse development indicate that changes in gene expression either precede or occur concomitantly with the major morphological transitions, that is, conversion of the oocyte to totipotent 2-cell blastomeres, compaction, and blastocyst formation. Using microarrays, we characterized global changes in gene expression and used Expression Analysis Systematic Explorer (EASE) to identify biological and molecular processes that accompany and likely underlie these transitions. The analysis confirmed previously described processes or events, but more important, EASE revealed new insights. Response to DNA damage and DNA repair genes are overrepresented in the oocyte compared to 1-cell through blastocyst stages and may reflect the oocyte's response to selective pressures to insure genomic integrity; fertilization results in changes in the transcript profile in the 1-cell embryo that are far greater than previously recognized; and genome activation during 2-cell stage may not be as global and promiscuous as previously proposed, but rather far more selective, with genes involved in transcription and RNA processing being preferentially expressed. These results validate this hypothesis-generating approach by identifying genes involved in critical biological processes that can be the subject of a more traditional hypothesis-driven approach.