Project description:Meiotic drivers subvert Mendelian expectations by manipulating reproductive development to bias their own transmission. Chromosomal drive typically functions in asymmetric female meiosis, while gene drive is normally postmeiotic and typically found in males. Cryptic drive is thought to be pervasive and can be unleashed following hybridization with a naïve genome, resulting in sterility and hybrid incompatibility. Using single molecule and single pollen genome sequencing, we describe an instance of gene drive in hybrids between maize (Zea mays ssp. mays) and teosinte mexicana (Zea mays ssp. mexicana), that depends on RNA interference (RNAi) in the male germline. Multiple hairpin-derived small RNA from mexicana target a novel domestication gene, Teosinte Drive Responder, that is required for pollen fertility and has undergone selection for immunity to RNAi. Introgression of mexicana into early cultivated maize is thought to have been critical to its geographical dispersal throughout the Americas. A survey of maize landraces and sympatric populations of teosinte mexicana reveals allelic bias at genes required for RNAi on at least 4 chromosomes that are also subject to gene drive in pollen from synthetic hybrids. Teosinte Pollen Drive likely played a major role in maize domestication, and offers an explanation for the widespread abundance of hairpin-encoded and other endogenous small RNA in the germlines of plants and animals.
Project description:Purpose: The goals of this study are studies the response of annual Zea mays ssp. mexicana L. under cold and drought stress Methods: The seedlings of zea may ssp. mexicana L. were generated by Illumina HiSeq2500 deep-sequencing. In order to generate a global overview of Zea mexicana transcriptome data, 3 of complement DNA (cDNA) libraries were prepared from RNA isolated from root, stem, and leave mixed tissues of Zea Mexicana from Control (24℃), Cold (4℃) and Drought (PEG2000, 20%) treatments and each teatment has two repetitions. The sequence reads that passed quality filters were merged and de novo to generate all transcripts set by Trinity with default parameter, which will be treated as reference genome. The number of paired-reads of each sample were mapped to reference genome by Bowtie software v1.1.1 and the number of mapped reads were calculated by RSEM. qRT-PCR validation was performed using BIO-RAD CFX96 sequence detection system and SYBR Green assays. Results: Using RNA-Seq technology with the Trinity assembled method, we generated a seedling plant transcriptome at a sequencing size of 51.78Gb of Zea mays ssp. mexicana L. from pooled RNA samples which included control (CK), cold (4℃) and drought (PEG2000, 20%) stressed plant samples. A total of 414,232,462 high quality clean reads were used to conduct de novo assembly and annotation of genes without reference genome information. All of these reads were assembled into 251,145 transcripts (N50 = 1,269 bp) and 184,280 unigenes (N50 = 923 bp). A total of 3,504 up-regulated and 1,220 down-regulated genes were detected under cold stress and 532 up-regulated and 82 down-regulated genes were detected under drought stress. A Venn diagram indicated that 208 genes were affected by both cold and drought stresses. 3 cold stress pathways and 5 drought related pathways showed significant KEGG pathways. Functional enrichment analyses identified many common or specific biological processes and gene sets in response to drought and cold stresses. The ABA dependent pathway, trehalose synthetic pathway and CBF6 gene of ICE1-CBF pathway may play important roles in the DEGs co-up-regulated by both stresses of Zea mays ssp. mexicana L. Conclusions: We analyzed transcriptome data and gene expression profile information from seedlings of Zea mays ssp. mexicana L. under cold and drought stresses. Together these data provides the most comprehensive sequence study available for Zea mays ssp. mexicana L. and provides some important functional genes and molecular mechanism information for improving the quality characteristic of maize in the future.
Project description:Psilocybe mushrooms, otherwise known as "magic" mushrooms, owe their psychedelic effect to psilocin, a serotonin subtype 2A (5-HT2A) receptor agonist and metabolite of psilocybin, the primary indole alkaloid found in Psilocybe species. Metabolomics is an advanced fingerprinting tool that can be utilized to identify the differences among fungal life stages that may otherwise be unaccounted for. In this study, by using targeted and untargeted (metabolomic) multivariate analysis, we demonstrate that the chemical composition of Psilocybe differs among mycelia, grain mycelia, and fruiting bodies. The preferential accumulation of psilocybin, baeocystin, tryptophan, ergothioneine, and phenylethylamine in fruiting bodies differentiated them from mycelia; however, the levels of alpha-glycerylphosphorylcholine (α-GPC), N-acetylglucosamine, and trimethylglycine were found to be proportionally higher in mycelia than in fruiting bodies based on Pareto-scaled data. Considering the wealth of compounds with therapeutic potential that have been isolated from various fungal genera, it would be pertinent to study the compounds found in Psilocybe mycelia as potential naturally derived therapeutic targets.