Project description:Small RNA libraries made from the rdr2/mop1 maize mutant, using RNA extracted from young ears (3 to 5 cm in length). Four libraries were constructed representing biological replicates. The mop1 mutant is depleted for heterochromatic siRNAs and enriched for 22-nt siRNAs of unknown function (as shown by Nobuta et al., 2008). These libraries were made in ~2010 but used for this study to assess the properties of the 22-nt, mop1-independent siRNAs.
Project description:Purpose: The goal of this study is to identify differentially expressed genes (DEGs) in immature ears between Barren inflorescence3 (Bif3) mutant and its wild-type siblings in maize. Methods: the 3-4 mm ear primordia of maize wild-type and Bif3 mutant were dissected from maize plant at the reproductive stage, and samples were snap freeze using liquid nitrogen. The total RNAs were prepared using RNeasy mini kit (Qiagen). All those RNA samples of wild-type and Bif3 mutant were submitted for RNA-Seq. Conclusions: Our RNA-seq experiments identified 1380 up- and 242 down-regulated genes (P < 0.05, FDR < 0.1, fold-change > 1.5).
Project description:In this study we used the maize (Zea mays) inflorescence to investigate gene networks that modulate determinacy, specifically the decision to allow branch growth. We characterized developmental transitions by associating spatiotemporal expression profiles with morphological changes resulting from genetic perturbations that disrupt steps in a pathway controlling branching. These are the RNA-seq datasets used in this study. We profiled changes in gene expression during normal maize ear and tassel development and in developing maize ear primordia upon genetic perturbation of the RAMOSA branching pathway. For the wild-type ear and tassel developmental series, greenhouse-grown B73 inbred plants were used. 10mm ears were collected and sectioned as follows from tip to base along the developmental gradient: tip 1mm sampled (tip; Inflorescence Meristem/Spikelet Pair Meristem), next 1mm discarded, next 1mm sampled (mid; Spikelet Meristem), next 2mm discarded, next 2 mm sampled (base; Floral Meristem), and immediately frozen in liquid nitrogen. Sections from ~30 sampled ears were pooled for each of 2 biological replicates to represent tip, mid, and base stages. Tassels were hand-dissected, measured, separated by stage: 1-2mm (stg1), 3-4mm (stg2), and 5-7mm (stg3), and immediately frozen in liquid N. For each stage, ~20-30 tassels were pooled for each of 2 biological replicates. For ramosa mutant series, segregating families (1:1) of ra1-R, ra2-R, and ra3-fea1 mutant alleles, all introgressed at least 6 times into the B73 inbred background, were grown at CSHL Uplands Farm. Field-grown plants were genotyped and collected 6-7 weeks after germination (V7-V8 stage). First and second ear primordia were immediately hand-dissected, measured, and frozen in liquid nitrogen. For ra1, ra2 and ra3 mutants and wild-type controls, ears were pooled into two size classes: 1) 1mm class included a range of 0.7-1.5mm sized ears and nine ears were pooled for each of 2 biological replicates; 2) 2mm class included a range of 1.8-2.5mm sized ears and six ears were pooled for each of three biological replicates. Wild-type samples were proportional mixtures of heterozygote siblings segregating in ra1, ra2, and ra3 populations. Variability factors (e.g. ear size within class, ear rank on the plant, and time of collection) were distributed evenly across pooled samples.
Project description:At 35 DAP whole kernels (pericarp + endosperm + embryo) without glumes of green house grown ears of heterozygous (+/bt2-H2328), self-pollinated plants were visually divided into pools of phenotypically normal looking kernels (small indentation, slightly smaller than mutant kernels, genotype +/+ or +/bt2-H2328) and pools of phenotypically mutant kernels (plump, round kernels, slightly larger than normal kernels, genotype bt2-H2328/bt2-H2328). Pools consisted of 4 kernels. 3 different ears were used for a biological duplicate. Experiment Overall Design: 4 arrays - maize
Project description:The present study profiled and analyzed gene expression of the maize ear at four key developmental stages. Based on genome-wide profile analysis, we detected differential mRNA of maize genes. Some of the differentially expressed genes (DEGs) were predicted to be potential candidates of maize ear development. Several well-known genes were found with reported mutants analyses, such as, compact plant2 (ct2), zea AGAMOUS homolog1 (zag1), bearded ear (bde), and silky1 (si1). MicroRNAs such as microRNA156 were predicted to target genes involved in maize ear development. Antisense transcripts were widespread throughout all the four stages, and are suspected to play important roles in maize ear development. Thus, identification and characterization of important genes and regulators at all the four developmental stages will contribute to an improved understanding of the molecular mechanisms responsible for maize ear development. Seeds of the maize inbred line 18-599 (Maize Research Institute, Sichuan Agricultural University, Chengdu, China) were grown in a growth chamber at 24°C/18°C (day/night) with 12 h illumination per day. Ears were collected as described previously [10] at four developmental stages: the growth point elongation, spikelet differentiation, floret primordium differentiation, and the floret organ differentiation phases. In brief, ears were manually collected at the four developmental stages. All the samples were harvested and immediately frozen in liquid nitrogen, and stored at -80°C until used for RNA isolation.
Project description:S. reilianum triggered loss of organ and meristem identity, and loss of meristem determinacy in male and female inflorescences and flowers. Microarray analysis showed that these developmental changes were accompanied with transcriptional regulation of genes proposed to regulate floral organ and meristem identity, and meristem determinacy in maize. Infected ears were compared with mock infected ears. Each treatment had 3 biological replicates Disease: S. reilianum-infected ears with elongated kernel: Zm_Sr5_15_2_Leafy ears4weeks_I, Zm_Sr5_15_2_Leafy ears4weeks_II, Zm_Sr5_15_2_Leafy ears4weeks_III Disease: Mock infected ears at: Zm_Sr5_15_2_Mock4weeks_I, Zm_Sr5_15_2_Mock4weeks_II, Zm_Sr5_15_2_Mock4weeks_III biological replicate: Zm_Sr5_15_2_Leafy ears4weeks_I, Zm_Sr5_15_2_Leafy ears4weeks_II, Zm_Sr5_15_2_Leafy ears4weeks_III biological replicate: Zm_Sr5_15_2_Mock4weeks_I, Zm_Sr5_15_2_Mock4weeks_II, Zm_Sr5_15_2_Mock4weeks_III
Project description:A maize array was fabricated with 5,376 unique expressed sequence tag (EST) clones sequenced from 4-day-old roots, immature ears and adult organ cDNA libraries. To elucidate organ relationships, relative mRNA levels were quantified by hybridization with embryos, three maize vegetative organs (leaf blades, leaf sheaths and roots) from multiple developmental stages, husk leaves and two types of floral organs (immature ears and silks). Clustering analyses of the hybridization data suggest that maize utilizes both the PEPCK and NADP-ME C(4) photosynthetic routes as genes in these pathways are co-regulated. Husk RNA has a gene-expression profile more similar to floral organs than to vegetative leaves. Only 7% of the genes were highly organ specific, showing over a fourfold difference in at least one of 12 comparisons and 37% showed a two- to fourfold difference. The majority of genes were expressed in diverse organs with little difference in transcript levels. Cross-hybridization among closely related genes within multigene families could obscure tissue specificity. As a first step in elucidating individual gene-expression patterns, we show that 45-nucleotide oligo probes produce signal intensities and signal ratios comparable to PCR probes on the same matrix. Gene-expression profile studies with cDNA microarrays provide a new molecular tool for defining plant organs and their relationships and for discovering new biological processes in silico. cDNA microarrays are insufficient for differentiating recently duplicated genes. Gene-specific oligo probes printed along with cDNA probes can query individual gene-expression profiles and gene families simultaneously. Keywords: other