Project description:We conducted micro-array analysis to quantify the global transcriptome variations in floral organs of a male and female tree allowing for identification of sex-linked transcripts. We used RNA samples from male floral buds in August and female floral buds in Spetemeber. Bud scale were removed. While the sampling time differed, the developmental stage of the floral organs was similar between the male and female.
Project description:We conducted micro-array analysis to quantify the global transcriptome variations in floral buds through the course of the year allowing for identification of changing developmental signals. We used RNA samples from floral buds, with bud scale removed, in the upper crown of a sexually mature Populus deltoides tree 2 hours after sunrise. Three independent samples of floral bud tissues with bud scales removes were collected from the upper crown of a single sexually mature male tree. RNA was extracted from tissues and hybridized on Affymetrix Genechip Poplar Genome Array.
Project description:We conducted micro-array analysis to quantify the global transcriptome variations in floral buds through the course of the year allowing for identification of changing developmental signals. We used RNA samples from floral buds, with bud scale removed, in the upper crown of a sexually mature Populus deltoides tree 2 hours after sunrise.
Project description:We conducted micro-array analysis to quantify the global transcriptome variations in floral organs of a male and female tree allowing for identification of sex-linked transcripts. We used RNA samples from male floral buds in August and female floral buds in September. Bud scale were removed. While the sampling time differed, the developmental stage of the floral organs was similar between the male and female. Five independent samples of floral bud tissues with bud scales removes were collected from the upper crown of a sexually mature male tree and female tree. RNA was extracted from tissues and hybridized on Affymetrix Genechip Poplar Genome Array.
Project description:Identification of differentially expressed genes from RNA-seq of normal and mantled male floral organs (staminodia) obtained from laser capture microdissection. Differential expression analysis was also conducted on normal and mantled female floral organs (carpel) using the same approach.
Project description:This study examined the transcriptome level attributes of a variety of Populus balsmifera tissues and organs. The tissues include seedlings grown under three light regimes, young leaves, mature leaves, roots, differentiating xylem, female catkins, and male catkins.
Project description:Poplar GeneChip was employed to detect genes expressed during the whole floral developmental process, in order to improve understanding of poplar flower development, since current knowledge on flower development was mainly from model plant Arabidopsis. Male and female floral buds of Populus tomentosa were selected at successive stages of the whole development process for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain genes contributed to floral development, but not the dynamic expression changes. To that end, equal amount of floral buds RNA per gender from different stages were mixed for the detection of expressed genes.
Project description:The debate on the origin and evolution of flowers has recently entered the field of developmental genetics, with focus on the design of the ancestral floral regulatory program. Flowers can differ dramatically among angiosperm lineages, but in general, sterile perianth organs surrounding stamens (male reproductive organs) and carpels (female reproductive organs) constitute the basic floral structure. However, the basal angiosperm lineages exhibit spectacular diversity in the number, arrangement, and structure, of floral organs, while the evolutionarily derived monocot and eudicot lineages share a far more uniform floral ground plan. As such, regulatory mechanisms underlying the archetypal floral plan, for instance that of the eudicot genetic model Arabidopsis thaliana, are unlikely to apply to the original flowers. Here we show that broadly overlapping transcriptional programs characterise the floral transcriptome of the basal angiosperm Persea americana (avocado), while floral gene expression domains are typically organ-specific in Arabidopsis. Our findings extend the “fading borders” model for basal angiosperms from organ identity genes to the downstream floral transcriptome, and suggest that the combinatorial mechanism for organ identity may not operate in basal angiosperms as it does in Arabidopsis. Furthermore, fading expression of components of the stamen transcriptome in central and peripheral regions of Persea flowers resembles the developmental program of the hypothesized gymnosperm “floral progenitor”. Accordingly, in contrast to the canalized organ-specific regulatory apparatus of Arabidopsis, floral development may have been originally regulated by overlapping transcriptional cascades with fading gradients of influence from focal to bordering organs.
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:One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performance of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust pathogen (Melampsora spp.), and a late frost event. This bodes well for the potential utility of these lines as advanced biofuels feedstocks.