Project description:In this study, we sequenced four small RNA libraries derived from mature pollens, in vitro germinated pollens, mature silks and pollinated silks of maize, respectively. In total, 161 known miRNAs belonging to 27 families and 82 novel miRNAs were identified. Of them, miRNAs involved in pollen-silk (pistil) interactions were analyzed. On the male side, miRNA differentially expressed between mature and germinated pollen were identified, some of them participate in pollen germination and tube growth. On the female side, silk-expressed miRNAs respond to pollination were also responsive to stresses, especially drought and fungal invasion. Furthermore, GO analysis of target genes revealed that members related to anxin signal transduction and gene expressional regulation were overrepresented.The results indicated that during pollen-silk interactions, miRNAs-mediated auxin signal transduction plays important roles, and miRNAs took part in complex transcriptional regulating network.
Project description:In this study, we sequenced four small RNA libraries derived from mature pollens, in vitro germinated pollens, mature silks and pollinated silks of maize, respectively. In total, 161 known miRNAs belonging to 27 families and 82 novel miRNAs were identified. Of them, miRNAs involved in pollen-silk (pistil) interactions were analyzed. On the male side, miRNA differentially expressed between mature and germinated pollen were identified, some of them participate in pollen germination and tube growth. On the female side, silk-expressed miRNAs respond to pollination were also responsive to stresses, especially drought and fungal invasion. Furthermore, GO analysis of target genes revealed that members related to anxin signal transduction and gene expressional regulation were overrepresented.The results indicated that during pollen-silk interactions, miRNAs-mediated auxin signal transduction plays important roles, and miRNAs took part in complex transcriptional regulating network. Examination of 4 different tissues of maize to provide novel information for understanding the post-transcriptional regulations of pollen-pistil interactions
Project description:we show that a short moderate heat stress during the tetrad stage of pollen development targets vital metabolic pathways ultimately leading to sterility and yield losses in maize.
Project description:Pollen grains are coated with a pollen wall which protects the microspore from various biotic and abiotic stresses, as well as facilitates male-female interaction. During pollen wall development, many compounds are transported from the tapetum to the developing pollen wall via tapetum-specific membrane transporters, and male sterility is often observed when membrane transporter’s function or localization is altered. Here, we show that mutating AP1/2β1 and AP1/2β2, two homologous genes of AP1/2β which encodes a large subunit shared by adaptor protein 1 (AP-1) and adaptor protein 2 (AP-2) complexes in Arabidopsis, impair pollen exine formation and cause reduced pollen germination rate and slowed pollen tube growth. However, the shared theory of AP1/2β is not proved in Arabidopsis.
Project description:In this study, RNA-seq based comparative transcriptome analysis was used to study the genetic response of maize silk to pollen tube penetration and in comparison to the fungal invasion of Fusarium graminearum and Ustilago maydis. RNA-seq libraries of 8 tissues were generated from leaf, root, seed, pollen tube, silk, pollinated silk, infected silk with Fusarium and infected silk with Ustilago.
Project description:P1 encodes an R2R3-MYB transcription factor responsible for the accumulation of insecticidal flavones in maize silks and red phlobaphene pigments in pericarps and other floral tissues, which contributed to making P1 an important visual marker since the dawn of modern genetics. We conducted RNA-Seq using from maize silks obtained at 2-3 days after emergence. High-throughput sequencing using the Illumina platform resulted in the generation of ~14 million high quality reads, corresponding to ~7 million reads for each sample, from which 76% aligned to the maize genome.
Project description:P1 encodes an R2R3-MYB transcription factor responsible for the accumulation of insecticidal flavones in maize silks and red phlobaphene pigments in pericarps and other floral tissues, which contributed to making P1 an important visual marker since the dawn of modern genetics. We conducted RNA-Seq using from maize silks obtained at 2-3 days after emergence. High-throughput sequencing using the Illumina platform resulted in the generation of ~14 million high quality reads, corresponding to ~7 million reads for each sample, from which 76% aligned to the maize genome. Examination of two different RNA samples from maize silks obtained at 2-3 days after emergence
Project description: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.
Project description:Flowering plants have immotile sperm that develop within pollen and must be carried to female gametes by a pollen tube. The pollen tube engages in molecular interactions with several cell types within the pistil and these interactions are essential for successful fertilization. We identified a group of three closely related pollen tube-expressed MYB transcription factors (MYB97, MYB101, MYB120), which are required for proper interaction of the pollen tube with the female gametophyte. These transcription factors are transcriptionally induced during growth in the pistil. They regulate a transcriptional network leading to proper differentiation and maturation of the pollen tube, promoting proper pollen tube-ovule interactions resulting in sperm release and double fertilization. We used microarrays to discover genes regulated by the transcription factors MYB97, MYB101 and MYB120 in pollen tubes growing through the pistil at 8 hours after pollination.