Project description:Bivalve mitochondrial genomes show many uncommon features, like additional genes, high rates of gene rearrangement, high A-T content. Moreover, Doubly Uniparental Inheritance (DUI) is a distinctive inheritance mechanism allowing some bivalves to maintain and transmit two separate sex-linked mitochondrial genomes. Many bivalve mitochondrial features, such as gene extensions or additional ORFs, have been proposed to be related to DUI but, up to now, this topic is far from being understood. Several species are known to show this unusual organelle inheritance but, being widespread only among Unionidae and Mytilidae, DUI distribution is unclear. We sequenced and characterized the complete female- (F) and male-transmitted (M) mitochondrial genomes of Meretrix lamarckii, which, in fact, is the second species of the family Veneridae where DUI has been demonstrated so far. The two mitochondrial genomes are comparable in length and show roughly the same gene content and order, except for three additional tRNAs found in the M one. The two sex-linked genomes show an average nucleotide divergence of 16%. A 100-aminoacid insertion in M. lamarckii M-cox2 gene was found; moreover, additional ORFs have been found in both F and M Long Unassigned Regions of M. lamarckii. Even if no direct involvement in DUI process has been demonstrated so far, the finding of cox2 insertions and supernumerary ORFs in M. lamarckii both strengthens this hypothesis and widens the taxonomical distribution of such unusual features. Finally, the analysis of inter-sex genetic variability shows that DUI species form two separate clusters, namely Unionidae and Mytilidae+Veneridae; this dichotomy is probably due to different DUI regimes acting on separate taxa.
Project description:Co-expression networks and gene regulatory networks (GRNs) are emerging as important tools for predicting the functional roles of individual genes at a system-wide scale. To enable network reconstructions we built a large-scale gene expression atlas comprised of 62,547 mRNAs, 17,862 non-modified proteins, and 6,227 phosphoproteins harboring 31,595 phosphorylation sites quantified across maize development. There was little edge conservation in co-expression and GRNs reconstructed using transcriptome versus proteome data yet networks from either data type were enriched in ontological categories and effective in predicting known regulatory relationships. This integrated gene expression atlas provides a valuable community resource. The networks should facilitate plant biology research and they provide a conceptual framework for future systems biology studies highlighting the importance of studying gene regulation at several levels.
Project description:Co-expression networks and gene regulatory networks (GRNs) are emerging as important tools for predicting the functional roles of individual genes at a system-wide scale. To enable network reconstructions we built a large-scale gene expression atlas comprised of 62,547 mRNAs, 17,862 non-modified proteins, and 6,227 phosphoproteins harboring 31,595 phosphorylation sites quantified across maize development. There was little edge conservation in co-expression and GRNs reconstructed using transcriptome versus proteome data yet networks from either data type were enriched in ontological categories and effective in predicting known regulatory relationships. This integrated gene expression atlas provides a valuable community resource. The networks should facilitate plant biology research and they provide a conceptual framework for future systems biology studies highlighting the importance of studying gene regulation at several levels.