Transcriptome evaluation of gene expression changes during carotenoid accumulation in the storage root of carrot (Daucus carota)
ABSTRACT: In this study, a cross species hybridization (CSH) approach was used to evaluate whole transcriptome changes during carotenoid accumulation in the storage root of carrot (Daucus carota). Carotenoids are isoprenoid compounds providing red, yellow and orange color to plants. Previous gene expression analyses of carotenoid accumulation in non-model plant species have primarily used a candidate gene approach. Since global transcriptome analyses require extensive genome sequence, in the absence of these genomic resources an alternate approach uses platforms developed for model plant species. To assess transcriptome patterns associated with carotenoid pigmentation in carrot storage root, two carrot sibling inbred lines, B8788, true breeding for orange color and B8750, true breeding for white root color, were hybridized to the Medicago Affymetrix GeneChip microarray. Near isogenic recombinant inbred lines B8788 and B8750, derived from a cross between white rooted wild carrot (QAL) and orange-rooted B493 were used for comparative analyzes to minimize background genetic differences. B8788 is true breeding for orange color whereas B8750 is true breeding for white storage root color. Carrots were grown in three pots for each genotype under greenhouse conditions and carrots were selected arbitrarily from these pots for harvest. Roots were harvested at approximately 11 weeks post planting when carotenoid accumulation becomes apparent in the storage root. Storage root tissue from sixteen individual carrot roots was pooled into three one-gram tissue pools of four carrots for each genotype.
Project description:Boihai Red is new strains of inter-specific hybridizing the bay scallop (Argopecten irradians irradians) with the Peruvian scallop (Argopecten purpuratus). Orange color variant of adductor muscle have been developed through successive selective breeding in this strain. In the present study,proteomic were conducted on orange and white adductor muscle tissues.Notably, 74 differentially expressed proteins (DEPs) were identified by lable free proteomics, including 36 up and 38 down regulated. In DEGs, apolipophorin, CYP450 and tyrosinase were expressed highly in orange adductor muscle tissues, which related to carotenoids or melanin. In DEPs, high expression of VPS and TIF in orange adductor muscle tissues indicated that proteins outside the carotenoid pathway might also affect carotenoid biosynthesis. In addition, RAB11A related to melanin was also expressed highly in orange adductor muscle tissues at protein level. It is probable that not only carotenoids, but also melanin act on orange color of adductor muscle. This study provides valuable genetic resources for understanding underlying mechanisms and pathways of adductor muscle color.
Project description:Color is an important trait in nature, playing a role in selection and speciation. The most important colorants in crustaceans are carotenoids, which in complexes with carotenoid-binding proteins provide an astonishing variety of colors from red to violet. Over 350 species and subspecies of amphipods (Crustacea: Amphipoda) endemic to Lake Baikal exhibit an impressive variability of colors and coloration patterns. However, the mechanisms forming this diversity are underexplored. In this work, we analyze the coloration of two species of endemic Lake Baikal amphipods, Eulimnogammarus cyaneus and E. vittatus. These species are brightly colored and, even more importantly, characterized by intraspecific color variability. We showed that the color of either species strongly correlated with the abundance of two putative carotenoid-binding proteins (the relative abundance of these proteins was higher in blue or teal-colored animals than in the orange- or yellow-colored ones.). With LC-MS/MS, we were able to identifiy these proteins, which turned out to be similar to the pheromone/odorant-binding protein family.
Project description:Cultivated carrot (Daucus carota L. ssp. sativus) was domesticated from wild carrot (Daucus carota L. ssp. carota) with radical different traits. The aim of this study was to compare the root transcriptomes between cultivated and wild carrots for SNP discovery, inferring domestication process, and identifying domestication genes. Six cultivated carrots representing main European carrot root types and five wild carrot populations from widely dispersed sites were used. The root transcriptomes were sequenced with multiplexing paried-end sequencing in Illumina Genome Analyzer IIx.
Project description:Multigene families encoding diverse secreted peptide hormones play important roles in plant development. A need exists to efficiently elucidate the structures and post-translational-modifications of these difficult-to-isolate peptide hormones in planta so that their biological functions can be determined. A mass spectrometry and bioinformatics approach was developed to comprehensively analyse the secreted peptidome of Medicago hairy root cultures and xylem sap. We identified 759 spectra corresponding to the secreted products of twelve peptide hormones including four CEP (C-TERMINALLY ENCODED PEPTIDE), two CLE (CLV3/ENDOSPERM SURROUNDING REGION RELATED) and six XAP (XYLEM SAP ASSOCIATED PEPTIDE) peptides. The MtCEP1, MtCEP2, MtCEP5 and MtCEP8 peptides identified differed in post-translational-modifications. Most were hydroxylated at conserved proline residues but some MtCEP1 derivatives were tri-arabinosylated. In addition, many CEP peptides possessed unexpected N- and C-terminal extensions. The pattern of these extensions suggested roles for endo- and exoproteases in CEP peptide maturation. Longer -than -expected, hydroxylated and homogeneously modified mono- and tri-arabinosylated CEP peptides corresponding to their in vivo structures were chemically synthesised to probe the effect of these post-translational-modifications on function. The ability of CEP peptides to elevate root nodule number was increased by hydroxylation at key positions. MtCEP1 peptides with N-terminal extensions or with tri-arabinosylation modification, however, were unable to impart increased nodulation. The MtCLE5 and MtCLE17 peptides identified were of precise size, and inhibited main root growth and increased lateral root number. Six XAP peptides, each beginning with a conserved DY sulfation motif, were identified including MtXAP1a, MtXAP1b, MtXAP1c, MtXAP3, MtXAP5 and MtXAP7. MtXAP1a and MtXAP5 inhibited lateral root emergence. Transcriptional analyses demonstrated peptide hormone gene expression in the root vasculature and tip. Since hairy roots can be induced on many plants, their corresponding root cultures may represent ideal source materials to efficiently identify diverse peptide hormones in vivo in a broad range of species.
Project description:• To dissect how the genes are dynamically and differentially expressed during fruit development in sweet orange, a comprehensive transcriptomic study was performed in a pleiotropic mutant (MT) and its wild type (WT). • The detection of the fruit transcriptomic changes was conducted at five stages of fruit development by deep sequencing; the obtained millions of reliable tags were mapped on orange unigenes and subjected to cluster analysis and functional categorization. Sugar and organic acid contents were determined based on the prediction of differential biological processes. • The global clustering analysis revealed a total of 14 expression patterns for the genes involved in fruit development of sweet orange. More than 94% of the genes showed differential expression during fruit development. Comparative transcripts profiling between WT and MT revealed that between 410 and 634 genes were significantly differentially expressed at the five stages. Functional categorization indicated that TCA cycle, carotenoid biosynthesis, and pentose phosphate pathway (OPP) were among the most regulated pathways. • This study provided a dynamic-view of the transcriptome changes during fruit ripening in sweet orange; the results highlighted a set of molecular processes involved in the formation of the mutation trait in the orange fruits. Overall design: Investigate the transcriptome changes during five fruit developmental stages of two sweet orange genotypes
Project description:To gain new insight into the underlying mechanism that may be involved in carotenoid biosynthesis, global gene expression at the transcriptional level was also investigated by RNA-seq analysis. The comparative analysis revealed extensive changes in the gene expression level of the orange-pericarp mutant (MT), which resulted in the down-regulation of 168 genes and the up-regulation of 135 genes. Gene ontology (GO) and KEGG pathway analysis indicated seven reliable metabolic pathways are altered in the mutant, including carbon metabolism, starch and sucrose metabolism and biosynthesis of amino acids. Overall design: Total six sample pools: the pericarp of WT and MT in ripe stage, each three biological replicates. The orange-pericarp mutant accumulates large amounts of β-carotene in the pericarp.
Project description:• To dissect how the genes are dynamically and differentially expressed during fruit development in sweet orange, a comprehensive transcriptomic study was performed in a pleiotropic mutant (MT) and its wild type (WT). • The detection of the fruit transcriptomic changes was conducted at five stages of fruit development by deep sequencing; the obtained millions of reliable tags were mapped on orange unigenes and subjected to cluster analysis and functional categorization. Sugar and organic acid contents were determined based on the prediction of differential biological processes. • The global clustering analysis revealed a total of 14 expression patterns for the genes involved in fruit development of sweet orange. More than 94% of the genes showed differential expression during fruit development. Comparative transcripts profiling between WT and MT revealed that between 410 and 634 genes were significantly differentially expressed at the five stages. Functional categorization indicated that TCA cycle, carotenoid biosynthesis, and pentose phosphate pathway (OPP) were among the most regulated pathways. • This study provided a dynamic-view of the transcriptome changes during fruit ripening in sweet orange; the results highlighted a set of molecular processes involved in the formation of the mutation trait in the orange fruits. Investigate the transcriptome changes during five fruit developmental stages of two sweet orange genotypes
Project description:Drought avoidance mechanism is one of the component mechanisms contributing for drought tolerance in which roots serves as the master keys, but poorly understood. Comparative analysis of drought stress responsive root transcriptome between drought-tolerant Nootripathu and drought-susceptible IR20 In this study, we used microarrays to dissect out drought responsive changes in roots of two contrasting rice genotypes viz., IR 20 (a shallow rooted lowland indica genotype) and Nootripathu (a deep rooted upland indica genotype) at molecular level. Overall design: Plants of two contrasting genotypes i.e. IR20 and Nootripathu were grown in 1m long PVC pipes and subjected to gradual drought stress. Root samples were collected from control and drought stressed plants for RNA extraction and used for hybridization on 52K Affymetrix rice genome expression arrays.
Project description:Petal is not only the target of selection by horticulturalists to enhance the ornamental value of plants but also emerged as a unique model system for plant organogenesis studies. It is known that three major groups of pigments, betalains, carotenoids and anthocyanins, are responsible for the attractive natural display of flower colors. While carotenoids and betalains generally yield yellow or red colors, anthocyanins confer a diverse range of color from orange to red to violet and blue. In this study, we collected 11 species (Erysimum cheiri, Malcolmia maritime, Brassica oleracea, Raphanus sativus, Orychophragmus violaceus, Eruca sativa, Orychophragmus violaceus, Iberis amara, Aubrieta x cultorum, Lobularia maritime, Matthiola incana) belong to different tribe in Brassicaceae family with varied flower color and performed petal transcriptome analysis. de novo transcriptome assembly showed that average length of the contigs varied from 631bp in O. violaceus to 1212bp in Matthiola incana which indicated that the complexity of the genomes are different much. Protein homology between these species and those sequenced species in Brassicaceae family are consistent with the known phylogenetic relationships. However, O. violaceus has closer relationships with Sisymbrium irio than expected Brassica species. Clustering analysis of genes in anthocyanin and carotenoids synthesis pathway indicated that while silence or low expression of CCD4 (Carotenoid Cleavage Dioxygenase 4) leading to the yellow color formation in different species, purple or red color variation might result from different genes expression variation. These results not only provide transcriptome data for petal development study but also provide useful information for Brassica flower improvement for ornamental purpose. Overall design: 22 samples were used here, each with two biological replicates. Gene expression value was calculated using the Arabidopsis as reference.