BioProject

The hybrid seed production was performed using the male sterility line, which is an important way of heterosis utilization in Chinese cabbage. More...

The hybrid seed production was performed using the male sterility line, which is an important way of heterosis utilization in Chinese cabbage. A stably inherited male sterile mutant msm was obtained from a Chinese cabbage DH line ‘FT’ using the isolated microspore culture combined with 60Co γ-rays mutagenesis. Compared to the wild type ‘FT’, the msm exhibited completely degenerated stamens and no pollen phenotype, and other characters had no significant difference except for stamen. The genetic analysis indicated that the msm mutant phenotype was controlled by a single recessive nuclear gene. Cytological observation showed that the stamen abortion of msm began at the tetrad period, and tapetum cells were abnormally expanded and highly vacuolated, leading to microspore abortion. Comparative transcriptome analysis on the flower buds of ‘FT’ and msm using RNA-Seq technology revealed a total of 1,653 differentially expressed genes (DEGs). Among which, a large number of genes associated with male sterility were found, including 64 pollen development and pollen tube growth-related genes, 94 pollen wall development-related genes, 11 phytohormone-related genes and 16 transcription factor-related genes, and the overwhelming majority of these genes were down-regulated in the msm vs. ‘FT’ comparison. Furthermore, KEGG pathway analysis indicated that a variety of carbohydrate metabolic and lipid metabolic pathways were significantly enriched, which may be related to pollen abortion. The expression patterns of 24 male sterility-related genes were analyzed using qRT-PCR. In addition, a total of 24,476 single nucleotide polymorphisms and 413,073 insertion-deletion events were specifically detected in msm. These results facilitate to elucidate the regulatory mechanisms of male sterility in Chinese cabbage. Overall design: The RNA from the developing flower buds of a male sterility mutant (msm) and its wild type‘FT’at the full-bloom stage in Chinese cabbage were sequenced by RNA-Seq, in triplicate. Less...