Microarray Analysis of myb80 versus Wild-Type Anthers
Ontology highlight
ABSTRACT: Arabidopsis thaliana MYB80 (formerly MYB103) is expressed in the tapetum and microspores between anther developmental stages 6 and 10. MYB80 encodes a MYB transcription factor that is essential for tapetal and pollen development. In order to identify the genes regulated by MYB80, microarray technology was employed to analyze the expression levels of genes that were differentially regulated in the myb80 mutant and wild- type anthers. Plant Cell 23:2209–2224 (2011)
Project description:Arabidopsis thaliana MYB80 (formerly MYB103) is expressed in the tapetum and microspores between anther developmental stages 6 and 10. MYB80 encodes a MYB transcription factor that is essential for tapetal and pollen development. In order to identify the genes regulated by MYB80, microarray technology was employed to analyze the expression levels of genes that were differentially regulated in the myb80 mutant and wild- type anthers. Plant Cell 23:2209–2224 (2011) three mutant chips vs three wild-type chips
Project description:Highly coordinated pollen wall patterning is essential for male reproductive development. However, the regulatory mechanisms involved in these processes remain poorly understood. Here, we report the identification of Defective Microspore Development1 (DMD1), which encodes a nuclear-localized protein possessing transactivation activity. DMD1 is preferentially expressed in the tapetum and microspores during postmeiotic anther development. Mutations in DMD1 cause a male sterile phenotype with impaired microspore cell integrity. The mutants display abnormal callose degradation, and primexine thickening is inhibited in the newly released microspores. The expression levels of several genes associated with callose degradation and primexine formation are down-regulated in dmd1 anthers. Moreover, irregular Ubisch body morphology and discontinuous endexine is observed in dmd1, and the baculum is completely absent. DMD1 interacts with Tapetum Degeneration Retardation (TDR), a basic helix-loop-helix transcription factor required for exine formation. Taken together, our results suggest that DMD1 is responsible for microspore cell integrity, primexine formation, and exine pattern formation during rice microspore development, and is a potential approach for manipulating male fertility in hybrid rice breeding.
Project description:Transcriptomic analysis of single, double and triple mutant anthers of bhlh010, bhlh089 and bhlh091. We examine here three recently duplicated Arabidopsis bHLH genes, bHLH010, bHLH089 and bHLH091, using evolutionary, genetic, morphological and transcriptomic approaches, and uncover their redundant functions in anther development. These three genes are relatively highly expressed in the tapetum of the Arabidopsis anther; single mutants at each of the bHLH010, bHLH089 and bHLH091 loci are developmentally normal, but the various double and triple combinations progressively exhibit increasingly defective anther phenotypes (abnormal tapetum morphology, delayed callose degeneration, and aborted pollen development), indicating their redundant functions in male fertility. Note: Samples in SRA were assigned the same sample accession. This is incorrect as there are different samples, hence “Source Name” was replaced with new values. Comment[ENA_SAMPLE] contains the original SRA sample accessions.
Project description:In maize, 24-nt phased, secondary small interfering RNAs (phasiRNAs) are abundant in meiotic stage anthers, but their distribution and functions are not precisely known. Using laser capture microdissection we analyzed tapetal cells, meiocytes, and other somatic cells at several stages of anther development to establish the timing of 24-PHAS precursor transcripts and the 24-nt phasiRNA products. By integrating RNA and small RNA (sRNA) profiling plus single-molecule and sRNA FISH (smFISH or sRNA-FISH) spatial detection, we demonstrate that the tapetum is the primary site of 24-PHAS precursor and Dcl5 transcripts and the resulting 24-nt phasiRNAs. Interestingly, 24-nt phasiRNAs accumulate in all cell types, with the highest levels in meiocytes, followed by tapetum. Our data support the conclusion that 24-nt phasiRNAs are mobile from tapetum to meiocytes and to other somatic cells. We discuss possible roles for 24-nt phasiRNAs in anther cell types.
Project description:In maize, 24-nt phased, secondary small interfering RNAs (phasiRNAs) are abundant in meiotic stage anthers, but their distribution and functions are not precisely known. Using laser capture microdissection (LCM), we analyzed tapetal cells, meiocytes, and other somatic cells at several stages of anther development to establish the timing of 24-PHAS precursor transcripts and the 24-nt phasiRNA products. This dataset includes 24-nt phasiRNA part of data. 24-nt phasiRNAs are found to accumulate in all cell types, with the highest levels in meiocytes, followed by tapetum.
Project description:The maize spikelet contains two florets, each of which contains three anthers. Morphologically, the anthers in the upper and lower florets proceed through the same developmental program. To test for global differences in gene expression between these anthers and to identify genes that are coordinately regulated during development, RNA isolated from upper and lower floret anthers at six developmental stages was used to hybridize cDNA microarrays. Approximately 9% of the tested genes exhibited statistically significant differences in gene expression between anthers in the upper and lower florets. This suggests that several basic biological processes are differentially regulated between upper and lower floret anthers, including photosynthesis, translation, and metabolism. To identify genes that are coordinately regulated during anther development, cluster analyses were performed. A variety of patterns of gene expression were observed. Five genes involved in programmed cell death were up-regulated at the time the tapetum begins to degenerate (i.e., the early microspore stage). This finding strongly supports the hypothesis that tapetal degeneration occurs via programmed cell death. In addition, many genes involved in protein synthesis exhibited differential expression patterns during anther development. Each microarray slide was scanned multiple times. This approach led to the identification an additional 30 to 40% of statistically significant differences in gene expression as compared to a single-scan strategy. Keywords: time course
Project description:N-terminal acetylation of proteins is a key modification in eukaryotes; however, our understanding of its biological function in plants is limited. Naa50 is the catalytic subunit of the protein N-terminal acetyltransferase NatE complex. We previously showed that the absence of Naa50 led to sterility in Arabidopsis thaliana. In the present study, we show that a lack of Naa50 in Arabidopsis resulted in collapsed and sterile pollen grains. Further study revealed that the mutation of Naa50 accelerated programmed cell death in the tapetum. Expression pattern analysis showed that Naa50 was specifically expressed in tapetal cells from anthers at stages 9–11 of pollen development, when tapetal programmed cell death occurs. Reciprocal cross analyses indicated that the male sterility of naa50 plants was due to sporophytic effects. Transcriptome sequencing of closed buds showed that the deletion of Naa50 resulted in up-regulation of the cysteine protease-coding gene CEP1 and impaired the expression of several genes that function in pollen wall deposition and pollen mitosis. Our findings suggest that Naa50 regulates cell degradation in the tapetum during anther development and plays an important role in pollen development by affecting several pathways.
Project description:Successful male gametogenesis involves orchestration of sequential gene regulation for somatic differentiation in pre-meiotic anthers. We report here the cloning of Male Sterile23 (Ms23), encoding an anther-specific predicted basic helix-loop-helix (bHLH) transcription factor required for tapetal differentiation; transcripts localize initially to the precursor secondary parietal cells then predominantly to daughter tapetal cells. In knockout ms23-ref mutant anthers, five instead of the normal four wall layers are observed. Microarray transcript profiling demonstrates a more severe developmental disruption in ms23-ref than in ms32 anthers, which possess a different bHLH defect. RNA-seq and proteomics data together with yeast two-hybrid assays suggest that MS23 along with MS32, bHLH122, and bHLH51 act sequentially as either homo- or heterodimers to choreograph tapetal development. Among them, MS23 is the earliest-acting factor, upstream of bHLH51 and bHLH122, controlling tapetal specification and maturation. In contrast, MS32 is constitutive and independently regulated and is required later than MS23 in tapetal differentiation. We characterized a maize (Zea mays) mutant line, ms23-ref, which the tapetal cells lack a dense cytoplasm and are not Binucleate -- the two characteristics of normal TP during meiosis. The meiocytes in ms23-ref fail to progress beyond meiotic prophase I. By profiling the small RNA population in ms23 mutants, we investigated the impact of ms23 mutation on small RNAs abundance in 0.4 mm, 0.7 mm, 1.0 mm, 1.5 mm and 2.0 mm anther. We also investigated the transcript abundance that were impacted in ms23 mutant by transcriptome profiling. The result provides an avenue for future research to understand the genetic networks and protein interactions among ms23, important for tapetal development in maize anther.
Project description:The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers) is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. Transcriptomic profiles of the 7B-1 male-sterile and wild type (WT) anthers were studied using mRNA sequencing (RNA-Seq). In total, 768 differentially expressed genes (DEGs) were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO) enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD) of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin) that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation.
Project description:In flowering plants, the male gametophyte, the pollen, develops in the anther. Complex patterns of gene expression in both the gametophytic and sporophytic tissues of the anther regulate this process. The gene expression profiles of the microspore/pollen and the sporophytic tapetum are of particular interest. In this study, a microarray technique combined with laser microdissection (44K LM-microarray) was developed and used to characterize separately the transcriptomes of the microspore/pollen and tapetum in rice. Expression profiles of 11 known tapetum specific-genes were consistent with previous reports. Based on the spatiotemporal expression patterns and gene ontology (GO) categories of anther-expressed genes, some noteworthy expression patterns are discussed in connection with various important biological events of anther development. The separated transcriptomes of rice microspore/pollen and tapetum were measured at the premeiosis, meiosis, tetrad, uninuclear, bicellular, and tricelluar stages by using laser microdissection (LM)-mediated microarray.