scholarly journals Coevolution in Hybrid Genomes: Nuclear-Encoded Rubisco Small Subunits and Their Plastid-Targeting Translocons Accompanying Sequential Allopolyploidy Events in Triticum

2020 ◽  
Vol 37 (12) ◽  
pp. 3409-3422
Author(s):  
Changping Li ◽  
Xiaofei Wang ◽  
Yaxian Xiao ◽  
Xuhan Sun ◽  
Jinbin Wang ◽  
...  
Keyword(s):  
Hexaploid Wheat ◽  
Protein Complexes ◽  
Chimeric Protein ◽  
Transit Peptide ◽  
D Genome ◽  
Bisphosphate Carboxylase ◽  
Allopolyploid Speciation ◽  
Genes Encoding ◽  
Rbcs Genes ◽  
Allohexaploid Wheat

Abstract The Triticum/Aegilops complex includes hybrid species resulting from homoploid hybrid speciation and allopolyploid speciation. Sequential allotetra- and allohexaploidy events presumably result in two challenges for the hybrids, which involve 1) cytonuclear stoichiometric disruptions caused by combining two diverged nuclear genomes with the maternal inheritance of the cytoplasmic organellar donor; and 2) incompatibility of chimeric protein complexes with diverged subunits from nuclear and cytoplasmic genomes. Here, we describe coevolution of nuclear rbcS genes encoding the small subunits of Rubisco (ribulose 1,5-bisphosphate carboxylase/oxygenase) and nuclear genes encoding plastid translocons, which mediate recognition and translocation of nuclear-encoded proteins into plastids, in allopolyploid wheat species. We demonstrate that intergenomic paternal-to-maternal gene conversion specifically occurred in the genic region of the homoeologous rbcS3 gene from the D-genome progenitor of wheat (abbreviated as rbcS3D) such that it encodes a maternal-like or B-subgenome-like SSU3D transit peptide in allohexaploid wheat but not in allotetraploid wheat. Divergent and limited interaction between SSU3D and the D-subgenomic TOC90D translocon subunit is implicated to underpin SSU3D targeting into the chloroplast of hexaploid wheat. This implicates early selection favoring individuals harboring optimal maternal-like organellar SSU3D targeting in hexaploid wheat. These data represent a novel dimension of cytonuclear evolution mediated by organellar targeting and transportation of nuclear proteins.

scholarly journals Protein complex formation in methionine chain-elongation and leucine biosynthesis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Li-Qun Chen ◽  
Shweta Chhajed ◽  
Tong Zhang ◽  
Joseph M. Collins ◽  
Qiuying Pang ◽  
...  
Keyword(s):  
Protein Complexes ◽  
Complete Characterization ◽  
Bimolecular Fluorescence Complementation ◽  
Chain Elongation ◽  
Substrate Channeling ◽  
Leucine Biosynthesis ◽  
Protein Complex Formation ◽  
Genes Encoding ◽  
Isopropylmalate Dehydrogenase

AbstractDuring the past two decades, glucosinolate (GLS) metabolic pathways have been under extensive studies because of the importance of the specialized metabolites in plant defense against herbivores and pathogens. The studies have led to a nearly complete characterization of biosynthetic genes in the reference plant Arabidopsis thaliana. Before methionine incorporation into the core structure of aliphatic GLS, it undergoes chain-elongation through an iterative three-step process recruited from leucine biosynthesis. Although enzymes catalyzing each step of the reaction have been characterized, the regulatory mode is largely unknown. In this study, using three independent approaches, yeast two-hybrid (Y2H), coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC), we uncovered the presence of protein complexes consisting of isopropylmalate isomerase (IPMI) and isopropylmalate dehydrogenase (IPMDH). In addition, simultaneous decreases in both IPMI and IPMDH activities in a leuc:ipmdh1 double mutants resulted in aggregated changes of GLS profiles compared to either leuc or ipmdh1 single mutants. Although the biological importance of the formation of IPMI and IPMDH protein complexes has not been documented in any organisms, these complexes may represent a new regulatory mechanism of substrate channeling in GLS and/or leucine biosynthesis. Since genes encoding the two enzymes are widely distributed in eukaryotic and prokaryotic genomes, such complexes may have universal significance in the regulation of leucine biosynthesis.

scholarly journals Frequent assembly of chimeric complexes in the protein interaction network of an interspecies yeast hybrid

2020 ◽  
Author(s):  
Rohan Dandage ◽  
Caroline M Berger ◽  
Isabelle Gagnon-Arsenault ◽  
Kyung-Mee Moon ◽  
Richard Greg Stacey ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Molecular Level ◽  
Yeast Species ◽  
Protein Complexes ◽  
Mitochondrial Protein ◽  
Chimeric Protein ◽  
Interaction Network ◽  
Protein Protein Interactions ◽  
Extreme Phenotypes ◽  
Yeast Hybrid

Abstract Hybrids between species often show extreme phenotypes, including some that take place at the molecular level. In this study, we investigated the phenotypes of an interspecies diploid hybrid in terms of protein-protein interactions inferred from protein correlation profiling. We used two yeast species, Saccharomyces cerevisiae and Saccharomyces uvarum, which are interfertile, but yet have proteins diverged enough to be differentiated using mass spectrometry. Most of the protein-protein interactions are similar between hybrid and parents, and are consistent with the assembly of chimeric complexes, which we validated using an orthogonal approach for the prefoldin complex. We also identified instances of altered protein-protein interactions in the hybrid, for instance in complexes related to proteostasis and in mitochondrial protein complexes. Overall, this study uncovers the likely frequent occurrence of chimeric protein complexes with few exceptions, which may result from incompatibilities or imbalances between the parental proteins.

scholarly journals Development of a D genome specific marker resource for diploid and hexaploid wheat

BMC Genomics ◽  
2015 ◽  
Vol 16 (1) ◽  
Author(s):  
Yi Wang ◽  
Thomas Drader ◽  
Vijay K. Tiwari ◽  
Lingli Dong ◽  
Ajay Kumar ◽  
...  
Keyword(s):  
Hexaploid Wheat ◽  
Specific Marker ◽  
D Genome

scholarly journals New genomic data and analyses challenge the traditional vision of animal epithelium evolution

2017 ◽  
Author(s):  
Hassiba Belahbib ◽  
Emmanuelle Renard ◽  
Sébastien Santini ◽  
Cyril Jourda ◽  
Jean-Michel Claverie ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cell Polarity ◽  
Protein Complexes ◽  
Genomic Data ◽  
Genes Encoding ◽  
Interaction Domains ◽  
Unexpected Findings ◽  
Crumbs Complex ◽  
Adhesive Type ◽  
E Cadherin

AbstractThe emergence of epithelia was the foundation of metazoan expansion. To investigate the early evolution of animal epithelia, we sequenced the genome and transcriptomes of two new sponge species to characterize epithelial markers such as the E-cadherin complex and the polarity complexes for all classes (Calcarea, Demospongiae, Hexactinellida, Homoscleromorpha) of sponges (phylum Porifera) and compare them with their homologs in Placozoa and in Ctenophora. We found that Placozoa and most sponges possess orthologs of all essential genes encoding proteins characteristic of bilaterian epithelial cells, as well as their conserved interaction domains. In stark contrast, we found that ctenophores lack several major polarity complex components such as the Crumbs complex and Scribble. Furthermore, the E-cadherin ctenophore ortholog exhibits a divergent cytoplasmic domain making it unlikely to interact with its canonical cytoplasmic partners. These unexpected findings challenge the current evolutionary paradigm on the emergence of epithelia.SIGNIFICANT STATEMENTEpithelial tissues are a hallmark of metazoans deeply linked to the evolution of the complex morphogenesis processes characterizing their development. However, studies on the epithelial features of non-bilaterians are still sparse and it remains unclear whether the last common metazoan ancestor possessed a fully functional epithelial toolkit or if it was acquired later during metazoan evolution. In this work, we demonstrate that if sponges have a well conserved and functionally predicted epithelial toolkit, Ctenophores have either divergent adhesion complexes or lack essential polarity complexes. Altogether, our results raise a doubt on the homology of protein complexes and structures involved in cell polarity and adhesive type junctions between Ctenophora and Bilateria epithelia.

scholarly journals The Tolerance of Salinity in Rice Requires the Presence of a Functional Copy of FLN2

Biomolecules ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 17 ◽  
Author(s):  
Guang Chen ◽  
Jiang Hu ◽  
Liuliu Dong ◽  
Dali Zeng ◽  
Longbiao Guo ◽  
...  
Keyword(s):  
Salinity Stress ◽  
Salinity Tolerance ◽  
Sugar Metabolism ◽  
Invertase Activity ◽  
Leaf Sheath ◽  
Japonica Rice ◽  
Wild Type ◽  
Bisphosphate Carboxylase ◽  
Genes Encoding ◽  
Knockout Line

A panel of ethane-methyl-sulfonate-mutagenized japonica rice lines was grown in the presence of salinity in order to identify genes required for the expression of salinity tolerance. A highly nontolerant selection proved to harbor a mutation in FLN2, a gene which encodes fructokinase-like protein2. Exposure of wild-type rice to salinity up-regulated FLN2, while a CRISPR/Cas9-generated FLN2 knockout line was hypersensitive to the stress. Both ribulose 1,5-bisphosphate carboxylase/oxygenase activity and the abundance of the transcript generated by a number of genes encoding components of sucrose synthesis were lower in the knockout line than in wild-type plants’ leaves, while the sucrose contents of the leaf and root were, respectively, markedly increased and decreased. That sugar partitioning to the roots was impaired in FLN2 knockout plants was confirmed by the observation that several genes involved in carbon transport were down-regulated in both the leaf and in the leaf sheath. The levels of sucrose synthase, acid invertase, and neutral invertase activity were distinctly lower in the knockout plants’ roots than in those of wild-type plants, particularly when the plants were exposed to salinity stress. The compromised salinity tolerance exhibited by the FLN2 knockout plants was likely a consequence of an inadequate supply of the assimilate required to support growth, a problem which was rectifiable by providing an exogenous supply of sucrose. The conclusion was that FLN2, on account of its influence over sugar metabolism, is important in the context of seedling growth and the rice plant’s response to salinity stress.

scholarly journals Rampant Nuclear Transfer and Substitutions of Plastid Genes in Passiflora

2020 ◽  
Vol 12 (8) ◽  
pp. 1313-1329 ◽  
Author(s):  
Bikash Shrestha ◽  
Lawrence E Gilbert ◽  
Tracey A Ruhlman ◽  
Robert K Jansen
Keyword(s):  
Nuclear Transfer ◽  
Protein Complexes ◽  
Nuclear Gene ◽  
Transit Peptide ◽  
Purifying Selection ◽  
Rna Recognition Motif ◽  
Rna Recognition ◽  
Plastid Genomes ◽  
Type Gene ◽  
Conserved Gene

Abstract Gene losses in plastid genomes (plastomes) are often accompanied by functional transfer to the nucleus or substitution of an alternative nuclear-encoded gene. Despite the highly conserved gene content in plastomes of photosynthetic land plants, recent gene loss events have been documented in several disparate angiosperm clades. Among these lineages, Passiflora lacks several essential ribosomal genes, rps7, rps16, rpl20, rpl22, and rpl32, the two largest plastid genes, ycf1 and ycf2, and has a highly divergent rpoA. Comparative transcriptome analyses were performed to determine the fate of the missing genes in Passiflora. Putative functional transfers of rps7, rpl22, and rpl32 to nucleus were detected, with the nuclear transfer of rps7, representing a novel event in angiosperms. Plastid-encoded rps7 was transferred into the intron of a nuclear-encoded plastid-targeted thioredoxin m-type gene, acquiring its plastid transit peptide (TP). Plastid rpl20 likely experienced a novel substitution by a duplicated, nuclear-encoded mitochondrial-targeted rpl20 that has a similar gene structure. Additionally, among rosids, evidence for a third independent transfer of rpl22 in Passiflora was detected that gained a TP from a nuclear gene containing an organelle RNA recognition motif. Nuclear transcripts representing rpoA, ycf1, and ycf2 were not detected. Further analyses suggest that the divergent rpoA remains functional and that the gene is under positive or purifying selection in different clades. Comparative analyses indicate that alternative translocon and motor protein complexes may have substituted for the loss of ycf1 and ycf2 in Passiflora.

More than one origin of hexaploid wheat is indicated by sequence comparison of low-copy DNA

Genome ◽  
1998 ◽  
Vol 41 (3) ◽  
pp. 402-407 ◽  
Author(s):  
L E Talbert ◽  
L Y Smith ◽  
N K Blake
Keyword(s):  
Dna Sequences ◽  
Hexaploid Wheat ◽  
Restriction Site ◽  
Cereal Crop ◽  
Crop Species ◽  
Wheat Evolution ◽  
D Genome ◽  
Restriction Site Variation ◽  
Site Variation ◽  
Copy Dna

Allohexaploid bread wheat is grown on more acreage than any other cereal crop, yet variation at the DNA level seems to be less than that observed in many diploid crop species. A common explanation for the small amount of DNA-level variation is that a severe bottleneck event resulted from the polyploidization events that gave rise to hexaploid wheat, whereby wheat was genetically separated from its progenitors. In this report, we test the extent of the bottleneck separating wheat from its D-genome progenitor, Triticum tauschii, by comparative DNA sequence analysis. Restriction site variation of low-copy DNA sequences amplified by PCR showed an average of 2.9 and 2.4 alleles per primer set in T. tauschii and wheat, respectively. Two different restriction patterns were present in T. tauschii for DNA amplified with a primer set for the A1 locus. Both alleles were also present in wheat. Alleles at the A1 locus were cloned and 527 bp of sequence obtained from 12 and 13 diverse accessions of wheat and T. tauschii, respectively. Average genetic distance among the wheat alleles was similar to that among the T. tauschii alleles (0.0127 and 0.0133, respectively). Nucleotide differences indicated that two distinct alleles existed in T. tauschii, both of which were present in wheat. These data suggest that hexaploid wheat formed at least twice, and that the bottleneck separating wheat from T. tauschii may be less constrictive than previously supposed.Key words: wheat, evolution, DNA.

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