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Red leaf lettuce (Lactuca sativaL.) is popular due to its high anthocyanin content, but poor leaf coloring often occurs under low light intensity. In order to reveal the mechanisms of anthocyanins affected by light intensity, we compared the transcriptome ofL. sativaL. var.capitataunder light intensities of 40 and 100 μmol m−2s−1. A total of 62,111 unigenes were de novo assembled with an N50 of 1,681 bp, and 48,435 unigenes were functionally annotated in public databases. A total of 3,899 differentially expressed genes (DEGs) were detected, of which 1,377 unigenes were up-regulated and 2,552 unigenes were down-regulated in the high light samples. By Kyoto Encyclopedia of Genes and Genomes enrichment analysis, the DEGs were significantly enriched in 14 pathways. Using gene annotation and phylogenetic analysis, we identified seven anthocyanin structural genes, includingCHS,CHI,F3H,F3′H,DFR,ANS, and3GT, and two anthocyanin transport genes,GSTandMATE. In terms of anthocyanin regulatory genes, five MYBs and one bHLH gene were identified. AnHY5gene was discovered, which may respond to light-signaling and regulate anthocyanin structural genes. These genes showed a log2FC of 2.7–9.0 under high irradiance, and were validated using quantitative real-time-PCR. In conclusion, our results indicated transcriptome variance in red leaf lettuce under low and high light intensity, and observed a anthocyanin biosynthesis and regulation pattern. The data should further help to unravel the molecular mechanisms of anthocyanins influenced by light intensity.

Xindao-18(Oryza sativa L. subsp. japonica Kato) were irratiated with a low-energy ion-beam, the growth form were observed and transcriptome of samples were sequenced by Illumina HiSeq2000 platform. The different expression genes were identified from transcriptomes control and treated samples. Finally, the coexpression of different gene expression were construce and seventy DEGs were annotated as transcription factor (TF). Among them, ten transcripts have the higher network density, and two genes, LOC_Os06g15330 and LOC_Os03g51970, had a still higher network density while elevate PCC paramater, which indicated that the indentified coexpression transcriptors may play important role in response to N+ ion beam treation.

Anthocyanin mainly responsible for flowers color in many plant species, it also accumulated in response to lots of environmental stress to reduce the damage to plant cell. Anthocyanin synthesis (ANS) protein is an important synthetase participated in anthocyanin biosynthetic pathway. In this study, we isolated the PsANS gene from transcriptome database built by our previous study. The PsANS gene contain an 1050bp open reading frame encoding 349 amino acid, phylogenetic analysis revealed that PsANS was segrated into a group with ANS from others plant species. Secondary and thri-dimension structure prediction also revealed that it may have similar function with ANS in others plant species. The identified PsANS gene would be helpful for further research in flower color modification and resistance breeding.

Heat shock proteins (Hsp) were usually regarded as chaperones and play important role in plant stress tolerance. The expression of Hsps would be inducted when plant encounter lots of environmental stressors. Lactuca sativa was an important leaf vegetable in the world, but thermol stress seriously restricted its production. In this study, we isolated the Hsp70 members from Lactuca sativa database, a total of 5 Hsp70 members with completed open reading frame (ORF) were selected and further analysized. Results showed that the 5 LsHsp70 members were closely to Hsp70s in Arabidopsis, which indicated that the identified Hsp70 may responsible for thermotolerance in Lactuca sativa. The 5 new Hsp70s would be used as candidated genes for improving the tolerance trait of Lactuca sativa and others plants.

BackgroundThe chloroplast (cp) genome is useful in plant systematics, genetic diversity analysis, molecular identification and divergence dating. The genusGentianacontains 362 species, but there are only two valuable complete cp genomes. The purpose of this study is to report the characterization of complete cp genome ofG. lawrenceivar.farreri, which is endemic to the Qinghai-Tibetan Plateau (QTP).MethodsUsing high throughput sequencing technology, we got the complete nucleotide sequence of theG. lawrenceivar.farrericp genome. The comparison analysis including genome difference and gene divergence was performed with its congeneric speciesG. straminea. The simple sequence repeats (SSRs) and phylogenetics were studied as well.ResultsThe cp genome ofG. lawrenceivar.farreriis a circular molecule of 138,750 bp, containing a pair of 24,653 bp inverted repeats which are separated by small and large single-copy regions of 11,365 and 78,082 bp, respectively. The cp genome contains 130 known genes, including 85 protein coding genes (PCGs), eight ribosomal RNA genes and 37 tRNA genes. Comparative analyses indicated thatG. lawrenceivar.farreriis 10,241 bp shorter than its congeneric speciesG. straminea.Four large gaps were detected that are responsible for 85% of the total sequence loss. Further detailed analyses revealed that 10 PCGs were included in the four gaps that encode nine NADH dehydrogenase subunits. The cp gene content, order and orientation are similar to those of its congeneric species, but with some variation among the PCGs. Three genes,ndhB,ndhFandclpP, have high nonsynonymous to synonymous values. There are 34 SSRs in theG. lawrenceivar.farrericp genome, of which 25 are mononucleotide repeats: no dinucleotide repeats were detected. Comparison with theG. stramineacp genome indicated that five SSRs have length polymorphisms and 23 SSRs are species-specific. The phylogenetic analysis of 48 PCGs from 12 Gentianales taxa cp genomes clearly identified three clades, which indicated the potential of cp genomes in phylogenetics.DiscussionThe “missing” sequence ofG. lawrenceivar.farrerimainly consistent ofndhgenes which could be dispensable under chilling-stressed conditions in the QTP. The complete cp genome sequence ofG. lawrenceivar.farreriprovides intragenic information that will contribute to genetic and phylogenetic research in the Gentianaceae.