Project description:affy_floralangers_rose - affy_floral_rose - - Which genes are induced during floral initiation? - Are the genes involved in floral initiation identical between our 3 genotypes? - Which genes are involved in the control of recurrent blooming in rose? - Which genes are diferentially expressed between buds that will become floral and buds that will remain vegetative?-This project aims to find in rose genes involved in flowering control (floral initiation and recurrent flowering). First, the floral initiation will be observed in 3 genotypes. Then we will check if same genes are regulated within genotypes for this process. Concerning recurrent blooming, we will compare flower bud versus vegetative buds in non-recurrent conditions and finally bud from non-recurrent and recurrent genotypes. Keywords: time course 26 arrays - rose
Project description:affy_floralangers_rose - affy_floral_rose - - Which genes are induced during floral initiation? - Are the genes involved in floral initiation identical between our 3 genotypes? - Which genes are involved in the control of recurrent blooming in rose? - Which genes are diferentially expressed between buds that will become floral and buds that will remain vegetative?-This project aims to find in rose genes involved in flowering control (floral initiation and recurrent flowering). First, the floral initiation will be observed in 3 genotypes. Then we will check if same genes are regulated within genotypes for this process. Concerning recurrent blooming, we will compare flower bud versus vegetative buds in non-recurrent conditions and finally bud from non-recurrent and recurrent genotypes. Keywords: time course
Project description:affy_cinetique_lyon_rose. The objective is to identify genes involved in petal development and senescence. R. chinensis cv Old Blush (OB) was used for the following reasons: it is a diploid Chinese rose that participated in the generation of modern roses (recurrent flowering, scent, etc.). The objective here is to identify genes whose expression is associated with different flower development stages, from floral meristem to senescing flower. These genes are putative candidates involved in floral initiation, development and senescence. All samples were collected at the same time early in the afternoon. Meristems and early flower development stages were dissected under a microscope. Total RNA was extracted from harvested tissues using the Plant RNA kit (Macherey Nagel), and then used to hybridize Rosa-Affymetrix microarrays. Keywords: time course 12 arrays - rose 6 developmental stages, 2 replicates each.
Project description:The MADS-domain transcription factor APETALA1 (AP1) is a key regulator of Arabidopsis flower development. To understand the molecular mechanisms underlying AP1 function, we identified its target genes during floral initiation using a combination of gene expression profiling and genome-wide binding studies. Many of its targets encode transcriptional regulators, including known floral repressors. The latter genes are down-regulated by AP1, suggesting that it initiates floral development by abrogating the inhibitory effects of these genes. While AP1 acts predominantly as a transcriptional repressor during the earliest stages of flower development, regulatory genes known to be required for floral organ formation were found to be activated by AP1 at more advanced stages, indicating a dynamic mode of action. Our results further imply that AP1 orchestrates floral initiation by integrating growth, patterning and hormonal pathways.
Project description:The MADS-domain transcription factor APETALA1 (AP1) is a key regulator of Arabidopsis flower development. To understand the molecular mechanisms underlying AP1 function, we identified its target genes during floral initiation using a combination of gene expression profiling and genome-wide binding studies. Many of its targets encode transcriptional regulators, including known floral repressors. The latter genes are down-regulated by AP1, suggesting that it initiates floral development by abrogating the inhibitory effects of these genes. While AP1 acts predominantly as a transcriptional repressor during the earliest stages of flower development, regulatory genes known to be required for floral organ formation were found to be activated by AP1 at more advanced stages, indicating a dynamic mode of action. Our results further imply that AP1 orchestrates floral initiation by integrating growth, patterning and hormonal pathways. We used the AP1-GR system to conduct chromatin immunoprecipitation experiments with AP1-specific antibodies followed by deep-sequencing (ChIP-Seq) in order to determine AP1 binding sites on a genome-wide scale. Samples were generated from tissue in which the AP1-GR protein was induced for 2h using a single treatment of 1 uM DEX to the shoot apex. As control, we performed ChIP experiments using the same antibody on uninduced tissue. Experiments were done in two biological replicates.
Project description:affy_cinetique_lyon_rose. The objective is to identify genes involved in petal development and senescence. R. chinensis cv Old Blush (OB) was used for the following reasons: it is a diploid Chinese rose that participated in the generation of modern roses (recurrent flowering, scent, etc.). The objective here is to identify genes whose expression is associated with different flower development stages, from floral meristem to senescing flower. These genes are putative candidates involved in floral initiation, development and senescence. All samples were collected at the same time early in the afternoon. Meristems and early flower development stages were dissected under a microscope. Total RNA was extracted from harvested tissues using the Plant RNA kit (Macherey Nagel), and then used to hybridize Rosa-Affymetrix microarrays. Keywords: time course
Project description:The transition to flowering is characterized by a shift of the shoot apical meristem (SAM) from leaf production to the initiation of a floral meristem. In this study, we addressed the nature of SAM gene networks involved in the early floral initiation process in the crop legume soybean. Unique aspects (such as pod development and nitrogen fixation) of legume development make them appealing for plant development studies. Soybean, a major oilseed crop, possesses varied maturity groups; hence, understanding and unravelling initial transition control has implications in manipulating crop yield. To this end, we performed global gene expression analysis using Affymetrix® soybean GeneChip® with RNA isolated from micro-dissected soybean SAMs at various time points after plants were shifted from long-day to short-day growth conditions. Analysis of the resulting microarray data revealed a total of 331 transcripts that have differential expression profiles. Intriguingly, about 20% of the transcripts affected by the switch in the development program have orthologs reported to be responsive to abscisic acid (ABA), suggesting an increase in ABA levels in the SAM during this developmental change. A subsequent immunoassay verified this, thereby implicating its possible function as an endogenous signal during the floral evocation process. The striking occurrence of abiotic stress-related transcripts, including trehalose metabolism genes, in SAMs during the early transition to floral meristems points to an overlap of abiotic stress and floral signalling pathways in soybean. In addition, other hormones - auxin, jasmonic acid and brassinosteroids - and a number of candidate protein kinases may also act in the signalling process prior to or concurrently with the induction of the putative floral homeiotic transcripts. This indicates that molecular events mediated by multiple hormonal pathways are part of the mechanism employed by soybean to regulate the floral transition process. Keywords: transcript profiling floral transition soybean shoot apical meristem
Project description:Our results showed that hundreds of differentially expressed genes (DEGs) were detected in floral sex initiation period, but thousands of DEGs were involved in stamens and ovules development process. Moreover, the DEGs were mainly showed up-regulation in male floral initiation, but mainly down-regulation in female floral initiation. Male floral initiation was associated with the flavonoid biosynthesis pathway while female floral initiation was related to the phytohormone signal transduction pathway. In addition, the floral organ identity genes played important roles in floral sex differentiation process and displayed a general conservation of the ABCDE model in J. curcas.
Project description:The transcription factors LEAFY (LFY) and APETALA1 (AP1), together with the AP1 paralog CAULIFLOWER (CAL), control the onset of flower development in a partially redundant manner. This redundancy is thought to be mediated, at least in part, through the regulation of a shared set of target genes. However, whether these genes are independently or cooperatively regulated by LFY and AP1/CAL, is currently unknown. To better understand the regulatory relationship between LFY and AP1/CAL during floral initiation, we monitored the activity of LFY in the absence of AP1/CAL function. We found that the regulation of several known LFY target genes is unaffected by AP1/CAL perturbation, while others appear to require AP1/CAL activity. Furthermore, we obtained evidence that LFY and AP1/CAL control the expression of some genes in an antagonistic manner. Notably, these include key regulators of floral initiation such TERMINAL FLOWER1 (TFL1), which had been previously reported to be directly repressed by both LFY and AP1. We show here that TFL1 expression is suppressed by AP1 but promoted by LFY. We further demonstrate that LFY has an inhibitory effect on flower formation in the absence of AP1/CAL activity. We propose that LFY and AP1/CAL may act as part of an incoherent feed-forward loop to control the establishment of a stable developmental program for the formation of flowers.
Project description:Photoautotrophically grown wild type Chlamydomonas reinhardtii cultures were either "treated" with 2uM rose bengal at 50 umol photons m-2 s-1 or "untreated" with the same volume of water at the same light intensity. The purpose is to identify genes that are regulated by singlet oxygen. Keywords: stress response