Project description:Lettuce (Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the 8 developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce.
Project description:Calcium deficiency response in liverwort, Arabidopsis and lettuce: (1) Marchantia polymorpha: M. polymorpha wildtype and Gβ-null mutant plants (Tak-1, gpb1-2) were grown in control liquid Yamagami media (2 mM Ca) for 6 days. For RNA-seq experiments, 6 day old gemmalings were transferred to calcium deficiency (0 mM Ca) media. Samples were collected at 48 h after the transfer. The transcriptomic profiles were collected from two independent batches. In total four biological replicates were used for each condition and each genotype for a total of 16 samples. (2) Arabidopsis thaliana: For Arabidopsis RNA-seq experiment, 6-day old seedlings grown on ½ strength MS media with sucrose were transferred to Yamagami media with 2 mM or 0 mM CaCl2 and treated for 7 days. (3) Lactuca Sativa: For lettuce RNA-seq, 4-day old seedlings grown on water agar (1%) were transferred to Yamagami media with 2 mM or 0.15 mM CaCl2 and treated for 7 days. In total four and three biological replicates were used for each condition for a total of 8 and 6 samples respectively for Arabidopsis and lettuce.
Project description:This study utilized the HIT-ISOseq method for high-throughput sequencing of RNA isoforms across multiple lettuce samples, generating millions of long reads per PacBio Sequel II SMRT Cell. Analysis of six tissue types revealed tissue-specific gene expression and RNA isoforms, facilitating updates to the lettuce reference genome annotation with expanded functional annotations.
Project description:Lettuce is one of most consumed vegetables globally. This crop is susceptible to abiotic stresses. To understand the molecular mechanisms of stress response in lettuce, global transcriptome analysis was conducted. This analysis revealed distinctive temporal expression patterns among the stress-regulated genes in lettuce plants exposed to abiotic stresses
Project description:The draft genome of L. sativa (lettuce) cv. Tizian was sequenced in two Illumina sequencing runs, mate pair and shotgun. This entry contains the RAW sequencing data.
Project description:Circular RNA (circRNA) is a covalently-closed single-stranded RNA molecule that plays an important role in transcriptional regulation of gene expression in a variety of species. Light intensity is a pivotal environmental factor affecting plant growth and development. However, little is known regarding photoresponsive plant circRNAs. Here, we aimed to investigate the expression and function of circRNAs in lettuce leaves in response to different light intensity treatments. We performed RNA sequencing (RNA-Seq) on leaves of lettuce (Lactuca sativa) to determine circRNA expression profiles and reverse-transcription polymerase chain reaction (PCR) to validate the candidate circRNA molecules. We then combined bioinformatics approach to explore the function of the parental genes of circRNA, including network, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway analysis. We identified 1650 circRNAs in lettuce, of which 1508 (86.40%) were derived from exons. Using real-time PCR, we characterized 10 validated differentially expressed circRNAs and their parental genes, all of which showed expression patterns consistent with RNA-Seq data. Interestingly, the expression of circRNA was, in some cases, inversely correlated with the expression of the parental gene. Furthermore, analysis of the circRNA–microRNA–mRNA network suggests that circRNAs may be involved in plant hormone signaling and chlorophyll metabolism during photoreactivity. These findings provide an essential reference basis for studying circRNAs’ biological mechanisms in light-treated plants.
Project description:Bolting is a key process in the growth and development of lettuce (Lactuca sativa L.). High temperature can induce earlier bolting which decreases in both quality and production of lettuce. However, knowledge underlying lettuce bolting is still lacking. To better understand the molecular basis of bolting, a comparative proteomics analysis was conducted on lettuce stems in the bolting period induced by high temperature (33 °C) compared with a control (20 °C) using iTRAQ-based proteomics, phenotypic measures, and biological verifications. High temperature induced lettuce bolting, while control temperature did not. Of the 6656 proteins identified, 758 proteins significantly altered their expression level induced by high-temperature relative to the control, of which 409 were up-regulated and 349 down-regulated. Proteins with abundance level change were mainly involved in photosynthesis, carbohydrate metabolism, stress response, hormone synthesis, and signal transduction. These differential proteins were mainly enriched in pathways associated with photosynthesis and tryptophan metabolism involving in auxin (IAA) biosynthesis. Among the differentially expressed proteins associated with photosynthesis and tryptophan metabolism were up-regulated. Moreover, in gibberellin (GA) biosynthesis pathway, 10 of main enzymes of P450 were up-regulated. Proteins related to SAUR and GRP, implicated in IAA and GA signal transduction were up-regulated, and the phosphorylation and ubiquitination related proteins regulating IAA and GA signal transduction were also induced. These findings indicate that a high temperature enhances the function of photosynthesis, IAA and GA synthesis and signal transduction to promote the process of bolting, which is in line with the physiology and transcription levels of IAA and GA metabolism. Our data provide a first comprehensive dataset for gaining novel understanding of the molecular basis underlying lettuce bolting induced by high temperature. It is potentially important for further functional analysis and genetic manipulation for molecular breeding to breed new cultivar of lettuce to restrain early bolting, which is vital for improving vegetable quality.
Project description:Whole genome microarray data were analyzed to describe the changes in gene transcription profile in human Caco-2 cancer cells under the influence of the extract from iodine-biofortified and non-fortified carrot and lettuce. These iodine-biofortified vegetables can be used as a functional food. Four-condition experiment: iodine-biofortified carrot, non-fortified carrot, iodine-biofortified lettuce, non-fortified lettuce vs. Caco-2 colorectal adenocarcinoma cell line. Three biological replicates and three technical replicates.