Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Chloroplast-genome-wide maps of small RNAs in Chinese cabbage (Brassica rapa) and Arabidopsis thaliana (Ler).

ABSTRACT: Deep sequencing provided evidence that a novel subset of small RNAs were derived from the chloroplast genome of Chinese cabbage (Brassica rapa) and Arabidopsis (Ler). The chloroplast small RNAs (csRNAs) include those derived from mRNA, rRNA, tRNA and intergenic RNA. The rRNA-derived csRNA were preferentially located at the 3M-CM-"M-BM-^@M-BM-^Y-ends of the rRNAs, while the tRNA-derived csRNAs were mainly located at 5M-CM-"M-BM-^@M-BM-^Y-termini of the tRNAs. After heat treatment, the abundance of csRNAs decreased in chinese cabbage seedlings, except those of 24 nt in length. The novel heat-responsive csRNAs and their locations in the chloroplast were verified by Northern blotting. The regulation of some csRNAs to the putative target genes were identified by real-time PCR. Our results indicated that high temperature regulated the production of some csRNAs, which may have potential roles in transcriptional or post-transcriptional regulation, and affected putative target genes expression in chloroplast. Examination of two replicates of heat treated (HT) and control (MT) Chinese cabbage sample respectively, and one Arabidopsis (Ler) RNA sample.

ORGANISM(S): Brassica rapa subsp. chinensis

SUBMITTER: Yu-ke He

PROVIDER: E-GEOD-28281 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Project description:The leaf of Chinese cabbage is the major place of photosynthesis, the mutation of leaf may directly affect the rate of plant growth and development and the formation of leafy head, and ultimately influence the yield and quality of Chinese cabbage. We identified a developmentally retarded mutant (drm) exhibiting stable inheritance, which was derived from Chinese cabbage DH line ‘FT’ using a combination of isolated microspore culture and radiation treatment (60Co γ-rays). The drm exhibited slow growth and development at the seedling and heading stages, leading to the production of a tiny, leafy head, as well as chlorophyll-deficient leaves, especially in seedlings. Genetic analysis indicated that the phenotype of drm was controlled by a single recessive nuclear gene. Compared with wild-type line ‘FT’, the drm’s chlorophyll content was significantly reduced and its chloroplast structure was abnormal. Moreover, the photosynthetic efficiency and chlorophyll fluorescence parameters were significantly decreased. The changes in leaf color, combined with these altered physiological characters may influence the growth and development of plant, ultimately resulting in the developmentally retarded phenotype of drm. To further understand the molecular regulatory mechanisms of phenotypic differences between ‘FT’ and drm, comparative transcriptome analysis were performed using RNA-Seq, a total of 338 differentially expressed genes (DEGs) were detected between ‘FT’ and drm. According to GO and KEGG pathway analysis, a number of DEGs which involved in the chlorophyll degradation and photosynthesis were identified, such as chlorophyllase and ribulose-1,5-bisphosphate carboxylase/oxygenase. In addition, the expression patterns of 12 DEGs, including three chlorophyll degradation- and photosynthesis-related genes and nine randomly selected genes, were confirmed by qRT-PCR. Numerous single nucleotide polymorphisms were also identified, providing a valuable resource for research and molecular marker-assistant breeding in Chinese cabbage. These results contribute to our understanding of the molecular regulatory mechanisms underlying growth and development and lay the foundation for future genetic and functional genomics studies in Chinese cabbage.

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