Project description:It has been reported that a number of small coding genes (30–100 amino acids) tend to be lineage-specifically emerged in evolution but such de-novo genes tend to be missed in genomes. Plant mitochondrial genomes might be fostering sources of de-novo genes because of a high rearrangement rate. However, the functional role of de-novo genes derived from mitochondria is unclear. Here, in the best model species of plants (Arabidopsis thaliana), we showed that Arabidopsis-specifically emerged de-novo genes derived from mitochondrial genome contributed to phenotypic variation in a species. We previously identified 49 candidates of small coding genes inducing abnormal morphological changes on overexpression in the nuclear genome. Among them, we focused on a candidate (sORF2146) potentially encoding 66 amino acids in large-scale intergenic genomic transferring region from mitochondrial genome. Comparative genome analysis showed that sORF2146 had been appeared in Arabidopsis lineage. Mitochondrial sORF2146 is fixed among A. thaliana ecotypes but nucleus sORF2146 is not fixed in A. thaliana ecotypes. After showing evidence that nucleus sORF2146 was transcribed and translated as a coding gene, we performed transcriptome analysis in transgenic plant overexpressing sORF2146. Genes associated with flowering transition are highly regulated in the transgenic plant. We then examined phenotypic effects of overexpression and knockdown transgenic plant. Overexpression and knockdown transgenic plant induce late and early flowering, respectively. Taken together, we conclude that a nucleus de-novo gene derived from mitochondria contributes to the variation of floral timing in Arabidopsis population.
Project description:To assess the clinical impact of splice-altering noncoding mutations in autism spectrum disorder (ASD), we used a deep learning framework (SpliceAI) to predict the splice-altering potential of de novo mutations in 3,953 individuals with ASD from the Simons Simplex Collection. To validate these predictions, we selected 36 individuals that harbored predicted de-novo cryptic splice mutations; each individual represented the only case of autism within their immediate family. We obtained peripheral blood-derived lymphoblastoid cell lines (LCLs) and performed high-depth mRNA sequencing (approximately 350 million 150 bp single-end reads per sample). We used OLego to align the reads against a reference created from hg19 by substituting de novo variants of each individual with the corresponding alternate allele.
Project description:Comparison of whole genome exome array CGH to a commercial SNP array for detection of de novo and homozygous copy number variants in 99 autism simplex trios. Will update once manuscript is prepared.
Project description:Transcriptional profiling of Arabidopsis thaliana 12-days old seedlings comparing Col-0 wild type with transgenic plants with altered expression of dual-targetting plastid/mitochondrial organellar RNA-polymerase RPOTmp. Transgenic plants used for experiment were: overexpressor plants obtained by transformation of Col-0 WT plants with genetic constructs created in [Tarasenko et al., 2016] contained catalytic part of RPOTmp enzyme with transit peptides of RPOTm (mitochondrial) and RPOTp (plastid) by agrobacterial transformation; plants with complementation of RPOTmp functions in mitochondria or chloroplasts obtained from transformation of GABI_286E07 rpotmp knockout-mutant plants with genetic constructs created in [Tarasenko et al., 2016]. Goal was to determine the effects of RPOTmp knockout/overexpression on global Arabidopsis thaliana gene expression.
Project description:Upon exposure to light, plant cells quickly acquire photosynthetic competence by converting pale etioplasts into green chloroplasts. This developmental transition involves the de novo biogenesis of the thylakoid system, and requires reprogramming of metabolism and gene expression. Etioplast-to-chloroplast differentiation involves massive changes in plastid ultrastructure, but how these changes are connected to specific changes in physiology, metabolism and expression of the plastid and nuclear genomes is poorly understood. Here a new experimental system in the dicotyledonous model plant tobacco (Nicotiana tabacum) that allows us to study the leaf de-etiolation process at the systems level. We have determined the accumulation kinetics of photosynthetic complexes, pigments, lipids and soluble metabolites, and recorded the dynamic changes in plastid ultrastructure and in the nuclear and plastid transcriptomes. Our data describe the greening process at high temporal resolution, resolve distinct genetic and metabolic phases during de-etiolation, and reveal numerous candidate genes that may be involved in light-induced chloroplast development and thylakoid biogenesis.
Project description:Activating mutations in tyrosine kinase (TK) genes (e.g. FLT3 and KIT) are found in more than 30% of patients with de novo acute myeloid leukemia (AML); many groups have speculated that mutations in other TK genes may be present in the remaining 70%. We performed high-throughput re-sequencing of the kinase domains of 26 TK genes (11 receptor TK and 15 cytoplasmic TK) that are expressed in most AML patients, using genomic DNA from the bone marrow (tumor) and matched skin biopsy samples (germline) from 94 patients with de novo AML; sequence variants were validated in an additional 94 AML tumor samples (14.3 million base pairs of sequence were obtained and analyzed). We identified known somatic mutations in FLT3, KIT, and JAK2 TK genes at the expected frequencies, and found four novel somatic mutations, JAK1V623A, JAK1T478S, DDR1A803V and NTRK1S677N, once each in four respective patients out of 188 tested. We also identified novel germline sequence changes encoding amino acid substitutions (i.e. non-synonymous changes) in 14 TK genes, including TYK2, which had the largest number of non-synonymous sequence variants (11 total detected). Additional studies will be required to define the roles that these somatic and germline TK gene variants play in AML pathogenesis. Experiment Overall Design: 188 patient samples analysed
Project description:This project is to explore the contribution of de novo mutations to severe structural malformations diagnosed prenatally using ultrasound. These malformations include heart, CNS, renal and GI abnormalities. In this pilot project we aim to exome sequence 30 parent-foetus trios to ~50X mean coverage and identify de novo functional variants using an algorithm developed in the Hurles group
Project description:This project is to explore the contribution of de novo mutations to severe structural malformations diagnosed prenatally using ultrasound. These malformations include heart, CNS, renal and GI abnormalities. In this pilot project we aim to exome sequence 30 parent-foetus trios to ~50X mean coverage and identify de novo functional variants using an algorithm developed in the Hurles group