Editorial Office BMC Biology The Origin and Evolution of a Two-Component System of Paralogous Genes Encoding the Centromeric Histone CENH3 in Cereals

Abstract Background: The cereal family Poaceae is one of the largest and most diverse angiosperm families. The central component of centromere specification and function is the centromere-specific histone H3 (CENH3). Some cereal species (maize, rice) have one copy of the CENH3 gene, while some (wheat, barley, rye) have two. We applied a homology-based approach to sequenced cereal genomes, in order to finally trace the mutual evolution of the structure of the CENH3 genes and the nearby regions in various tribes. Results: We have established that the syntenic group or the CENH3 locus with the CENH3 gene and the boundaries defined by the Cdpk2 and bZip genes first appeared around 50 Mya in a common ancestor of the subfamilies Bambusoideae, Oryzoideae and Pooideae. This locus came to Pooideae with one copy of CENH3 in the most ancient tribes Nardeae and Meliceae. The βCENH3 gene as a part of the locus appeared in the tribes Stipeae and Brachypodieae around 35-40 Mya. The duplication was accompanied by changes in the exon-intron structure. Purifying selection acts mostly on αCENH3s, while βCENH3s form more heterogeneous structures, in which clade-specific amino acid motifs are present. In barley species, the βCENH3 gene assumed an inverted orientation relative to αCENH3 and the Cdpk2 gene was substituted with Cbp3c. As the evolutionary and breeding processes went on, the locus was growing in size due to an increasing distance between αCENH3 and βCENH3 because of a massive insertion of the main LTR-containing retrotransposon superfamilies, gypsy and copia, without any evolutionary preference on either of them. A comparison of the molecular structure of the locus in the A, B and D subgenomes of the hexaploid wheat T. aestivum showed that invasion by mobile elements and concomitant rearrangements took place in an independent way even in evolutionarily close species. Conclusions: The CENH3 duplication in cereals was accompanied by changes in the exon-intron structure of the βCENH3 paralog, which it was not in other plant taxa. The observed general tendency towards the expansion of the CENH3 locus reveals an amazing diversity of ways in which different species implement the scenario described in this paper.

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The origin and evolution of a two-component system of paralogous genes encoding the centromeric histone CENH3 in cereals

BMC Plant Biology ◽

10.1186/s12870-021-03264-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Evgeny A. Elisafenko ◽

Elena V. Evtushenko ◽

Alexander V. Vershinin

Keyword(s):

Purifying Selection ◽

Central Component ◽

General Tendency ◽

Gene Encoding ◽

Syntenic Group ◽

Origin And Evolution ◽

Cereal Species ◽

Genes Encoding ◽

Intron Structure ◽

And Function

Abstract Background The cereal family Poaceae is one of the largest and most diverse angiosperm families. The central component of centromere specification and function is the centromere-specific histone H3 (CENH3). Some cereal species (maize, rice) have one copy of the gene encoding this protein, while some (wheat, barley, rye) have two. We applied a homology-based approach to sequenced cereal genomes, in order to finally trace the mutual evolution of the structure of the CENH3 genes and the nearby regions in various tribes. Results We have established that the syntenic group or the CENH3 locus with the CENH3 gene and the boundaries defined by the CDPK2 and bZIP genes first appeared around 50 Mya in a common ancestor of the subfamilies Bambusoideae, Oryzoideae and Pooideae. This locus came to Pooideae with one copy of CENH3 in the most ancient tribes Nardeae and Meliceae. The βCENH3 gene as a part of the locus appeared in the tribes Stipeae and Brachypodieae around 35–40 Mya. The duplication was accompanied by changes in the exon-intron structure. Purifying selection acts mostly on αCENH3s, while βCENH3s form more heterogeneous structures, in which clade-specific amino acid motifs are present. In barley species, the βCENH3 gene assumed an inverted orientation relative to αCENH3 and the CDPK2 gene was substituted with LHCB-l. As the evolution and domestication of plant species went on, the locus was growing in size due to an increasing distance between αCENH3 and βCENH3 because of a massive insertion of the main LTR-containing retrotransposon superfamilies, gypsy and copia, without any evolutionary preference on either of them. A comparison of the molecular structure of the locus in the A, B and D subgenomes of the hexaploid wheat T. aestivum showed that invasion by mobile elements and concomitant rearrangements took place in an independent way even in evolutionarily close species. Conclusions The CENH3 duplication in cereals was accompanied by changes in the exon-intron structure of the βCENH3 paralog. The observed general tendency towards the expansion of the CENH3 locus reveals an amazing diversity of ways in which different species implement the scenario described in this paper.

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Origin and evolution of overlapping genes in the family Microviridae

Journal of General Virology ◽

10.1099/vir.0.81375-0 ◽

2006 ◽

Vol 87 (4) ◽

pp. 1013-1017 ◽

Cited By ~ 41

Author(s):

Angelo Pavesi

Keyword(s):

Purifying Selection ◽

Synonymous Substitution ◽

Ancestral State ◽

Overlapping Genes ◽

Novel Genes ◽

Origin And Evolution ◽

The Family ◽

Genes Encoding ◽

Phage Growth ◽

Gene Overlap

The possibility of creating novel genes from pre-existing sequences, known as overprinting, is a widespread phenomenon in small viruses. Here, the origin and evolution of gene overlap in the bacteriophages belonging to the family Microviridae have been investigated. The distinction between ancestral and derived frames was carried out by comparing the patterns of codon usage in overlapping and non-overlapping genes. By this approach, a gradual increase in complexity of the phage genome – from an ancestral state lacking gene overlap to a derived state with a high density of genetic information – was inferred. Genes encoding less-essential proteins, yet playing a role in phage growth and diffusion, were predicted to be novel genes that originated by overprinting. Evaluation of the rates of synonymous and non-synonymous substitution yielded evidence for overlapping genes under positive selection in one frame and purifying selection in the alternative frame.

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Expression of Two Rye CENH3 Variants and Their Loading into Centromeres

Plants ◽

10.3390/plants10102043 ◽

2021 ◽

Vol 10 (10) ◽

pp. 2043

Author(s):

Elena V. Evtushenko ◽

Evgeny A. Elisafenko ◽

Sima S. Gatzkaya ◽

Veit Schubert ◽

Andreas Houben ◽

...

Keyword(s):

Gene Dosage ◽

Central Component ◽

Gene Encoding ◽

Gene Dosage Effect ◽

Centromeric Chromatin ◽

Gene Copies ◽

Cereal Species ◽

Secale Cereale L ◽

And Function ◽

Mitosis And Meiosis

Gene duplication and the preservation of both copies during evolution is an intriguing evolutionary phenomenon. Their preservation is related to the function they perform. The central component of centromere specification and function is the centromere-specific histone H3 (CENH3). Some cereal species (maize, rice) have one copy of the gene encoding this protein, while some (wheat, barley, rye) have two. Therefore, they represent a good model for a comparative study of the functional activity of the duplicated CENH3 genes and their protein products. We determined the organization of the CENH3 locus in rye (Secale cereale L.) and identified the functional motifs in the vicinity of the CENH3 genes. We compared the expression of these genes at different stages of plant development and the loading of their products, the CENH3 proteins, into nucleosomes during mitosis and meiosis. Using extended chromatin fibers, we revealed patterns of loading CENH3proteinsinto polynucleosomal domains in centromeric chromatin. Our results indicate no sign of neofunctionalization, subfunctionalization or specialization in the gene copies. The influence of negative selection on the coding part of the genes led them to preserve their conserved function. The advantage of having two functional genes appears as the gene-dosage effect.

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A Family of Genes Clustered at the Triplo-lethal Locus of Drosophila melanogaster Has an Unusual Evolutionary History and Significant Synteny With Anopheles gambiae

Genetics ◽

10.1093/genetics/165.2.613 ◽

2003 ◽

Vol 165 (2) ◽

pp. 613-621 ◽

Cited By ~ 2

Author(s):

Douglas R Dorer ◽

Jamie A Rudnick ◽

Etsuko N Moriyama ◽

Alan C Christensen

Keyword(s):

Phylogenetic Analysis ◽

Drosophila Melanogaster ◽

Anopheles Gambiae ◽

Evolutionary History ◽

Codon Bias ◽

Good Target ◽

The Family ◽

Genes Encoding ◽

And Function ◽

Gambiae Genome

Abstract Within the unique Triplo-lethal region (Tpl) of the Drosophila melanogaster genome we have found a cluster of 20 genes encoding a novel family of proteins. This family is also present in the Anopheles gambiae genome and displays remarkable synteny and sequence conservation with the Drosophila cluster. The family is also present in the sequenced genome of D. pseudoobscura, and homologs have been found in Aedes aegypti mosquitoes and in four other insect orders, but it is not present in the sequenced genome of any noninsect species. Phylogenetic analysis suggests that the cluster evolved prior to the divergence of Drosophila and Anopheles (250 MYA) and has been highly conserved since. The ratio of synonymous to nonsynonymous substitutions and the high codon bias suggest that there has been selection on this family both for expression level and function. We hypothesize that this gene family is Tpl, name it the Osiris family, and consider possible functions. We also predict that this family of proteins, due to the unique dosage sensitivity and the lack of homologs in noninsect species, would be a good target for genetic engineering or novel insecticides.

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Spine impairment in mice high-expressing neuregulin 1 due to LIMK1 activation

Cell Death and Disease ◽

10.1038/s41419-021-03687-8 ◽

2021 ◽

Vol 12 (4) ◽

Author(s):

Peng Chen ◽

Hongyang Jing ◽

Mingtao Xiong ◽

Qian Zhang ◽

Dong Lin ◽

...

Keyword(s):

Neural Development ◽

Protein Level ◽

Brain Regions ◽

Postmortem Brain ◽

Pathophysiological Mechanism ◽

Brain Disorders ◽

Spine Density ◽

Genes Encoding ◽

High Level ◽

And Function

AbstractThe genes encoding for neuregulin1 (NRG1), a growth factor, and its receptor ErbB4 are both risk factors of major depression disorder and schizophrenia (SZ). They have been implicated in neural development and synaptic plasticity. However, exactly how NRG1 variations lead to SZ remains unclear. Indeed, NRG1 levels are increased in postmortem brain tissues of patients with brain disorders. Here, we studied the effects of high-level NRG1 on dendritic spine development and function. We showed that spine density in the prefrontal cortex and hippocampus was reduced in mice (ctoNrg1) that overexpressed NRG1 in neurons. The frequency of miniature excitatory postsynaptic currents (mEPSCs) was reduced in both brain regions of ctoNrg1 mice. High expression of NRG1 activated LIMK1 and increased cofilin phosphorylation in postsynaptic densities. Spine reduction was attenuated by inhibiting LIMK1 or blocking the NRG1–LIMK1 interaction, or by restoring NRG1 protein level. These results indicate that a normal NRG1 protein level is necessary for spine homeostasis and suggest a pathophysiological mechanism of abnormal spines in relevant brain disorders.

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Congenital neutropenia

Hematology ◽

10.1182/asheducation-2009.1.344 ◽

2009 ◽

Vol 2009 (1) ◽

pp. 344-350 ◽

Cited By ~ 24

Author(s):

Christoph Klein

Keyword(s):

Ribosomal Proteins ◽

Mitochondrial Proteins ◽

Phenotypic Traits ◽

Genetic Defects ◽

Congenital Neutropenia ◽

Lysosomal Function ◽

Genes Encoding ◽

And Function ◽

Neutrophil Differentiation ◽

Remarkable Progress

Abstract Congenital neutropenia comprises a variety of genetically heterogeneous phenotypic traits. Molecular elucidation of the underlying genetic defects has yielded important insights into the physiology of neutrophil differentiation and function. Non-syndromic variants of congenital neutropenia are caused by mutations in ELA2, HAX1, GFI1, or WAS. Syndromic variants of congenital neutropenia may be due to mutations in genes controlling glucose metabolism (SLC37A4, G6PC3) or lysosomal function (LYST, RAB27A, ROBLD3/p14, AP3B1, VPS13B). Furthermore, defects in genes encoding ribosomal proteins (SBDS, RMRP) and mitochondrial proteins (AK2, TAZ) are associated with congenital neutropenia syndromes. Despite remarkable progress in the field, many patients with congenital neutropenia cannot yet definitively be classified by genetic terms. This review addresses diagnostic and therapeutic aspects of congenital neutropenia and covers recent molecular and pathophysiological insights of selected congenital neutropenia syndromes.

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Enhancing and inhibitory motifs have coevolved to regulate CD4 activity

10.1101/2021.04.29.441928 ◽

2021 ◽

Author(s):

Mark S. Lee ◽

Peter J. Tuohy ◽

Caleb Kim ◽

Katrina Lichauco ◽

Heather L. Parrish ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Receptor ◽

Purifying Selection ◽

Cell Receptor ◽

Specific Information ◽

Transmembrane Receptors ◽

Peptide Antigens ◽

And Function ◽

Intracellular Domains

SUMMARYCD4+ T cells use T cell receptor (TCR)-CD3 complexes, and CD4, to respond to peptide antigens within MHCII molecules (pMHCII). We report here that, through ∼435 million years of evolution in jawed vertebrates, purifying selection has shaped motifs in the extracellular, transmembrane, and intracellular domains of eutherian CD4 that both enhance pMHCII responses and are coevolving with residues in an intracellular motif that inhibits pMHCII responses. Importantly, while CD4 interactions with the Src kinase, Lck, are classically viewed as the key determinant of CD4’s contribution to pMHCII responses, we found that without the inhibitory motif CD4-Lck interactions are not necessary for robust responses to pMHCII. In summary, motifs that mediate events on the outside and inside of CD4+ T cells coevolved to finetune the relay of pMHCII-specific information across the membrane. These results have implications for the evolution and function of complex transmembrane receptors and for biomimetic engineering.

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Reconstitution of the Human tRNA Splicing Endonuclease Complex: insight into the regulation of pre-tRNA cleavage

10.1101/2019.12.16.878546 ◽

2019 ◽

Author(s):

Cassandra K. Hayne ◽

Casey A. Schmidt ◽

A. Gregory Matera ◽

Robin E. Stanley

Keyword(s):

Animal Cells ◽

Trna Splicing ◽

Polynucleotide Kinase ◽

Genes Encoding ◽

Intron Removal ◽

And Function ◽

Insight Into ◽

Negative Modulator

ABSTRACTThe splicing of tRNA introns is a critical step in pre-tRNA maturation. In archaea and eukaryotes, tRNA intron removal is catalyzed by the tRNA splicing endonuclease (TSEN) complex. Eukaryotic TSEN is comprised of four core subunits (TSEN54, TSEN2, TSEN34, and TSEN15). The human TSEN complex additionally co-purifies with the polynucleotide kinase CLP1; however, CLP1’s role in tRNA splicing remains unclear. Mutations in genes encoding all four TSEN subunits, as well as CLP1, are known to cause neurodegenerative disorders, yet the mechanisms underlying the pathogenesis of these disorders are unknown. Here, we developed a recombinant system that produces active TSEN complex. Co-expression of all four TSEN subunits is required for efficient formation and function of the complex. We show that human CLP1 associates with the active TSEN complex, but is not required for tRNA intron cleavage in vitro. Moreover, RNAi knockdown of the Drosophila CLP1 orthologue, cbc, promotes biogenesis of mature tRNAs and circularized tRNA introns (tricRNAs) in vivo. Collectively, these and other findings suggest that CLP1/cbc plays a regulatory role in tRNA splicing by serving as a negative modulator of the direct tRNA ligation pathway in animal cells.

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The BAHD Gene Family in Cacao (Theobroma cacao, Malvaceae): Genome-Wide Identification and Expression Analysis

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.707708 ◽

2021 ◽

Vol 9 ◽

Author(s):

Abdullah ◽

Sahar Faraji ◽

Parviz Heidari ◽

Péter Poczai

Keyword(s):

Gene Family ◽

Theobroma Cacao ◽

Critical Role ◽

Divergence Time ◽

Purifying Selection ◽

Plant Metabolites ◽

Corchorus Capsularis ◽

Cell Stability ◽

Duplication Events ◽

And Function

The benzyl alcohol O-acetyl transferase, anthocyanin O-hydroxycinnamoyl transferase, N-hydroxycinnamoyl anthranilate benzoyl transferase, and deacetylvindoline 4-O-acetyltransferase (BAHD) enzymes play a critical role in regulating plant metabolites and affecting cell stability. In the present study, members of the BAHD gene family were recognized in the genome of Theobroma cacao and characterized using various bioinformatics tools. We found 27 non-redundant putative tcBAHD genes in cacao for the first time. Our findings indicate that tcBAHD genes are diverse based on sequence structure, physiochemical properties, and function. When analyzed with BAHDs of Gossypium raimondii and Corchorus capsularis clustered into four main groups. According to phylogenetic analysis, BAHD genes probably evolved drastically after their divergence. The divergence time of duplication events with purifying selection pressure was predicted to range from 1.82 to 15.50 MYA. Pocket analysis revealed that serine amino acid is more common in the binding site than other residuals, reflecting its key role in regulating the activity of tcBAHDs. Furthermore, cis-acting elements related to the responsiveness of stress and hormone, particularly ABA and MeJA, were frequently observed in the promoter region of tcBAHD genes. RNA-seq analysis further illustrated that tcBAHD13 and tcBAHD26 are involved in response to Phytophthora megakarya fungi. In conclusion, it is likely that evolutionary processes, such as duplication events, have caused high diversity in the structure and function of tcBAHD genes.

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Effects of SEL-12 presenilin on LIN-12 localization and function in Caenorhabditis elegans

Development ◽

10.1242/dev.125.18.3599 ◽

1998 ◽

Vol 125 (18) ◽

pp. 3599-3606 ◽

Cited By ~ 4

Author(s):

D. Levitan ◽

I. Greenwald

Keyword(s):

Plasma Membranes ◽

General Factor ◽

Missense Mutations ◽

Protein Activity ◽

App Processing ◽

Notch Activity ◽

C Elegans ◽

Vulval Precursor Cells ◽

Genes Encoding ◽

And Function

Presenilins have been implicated in the development of Alzheimer's disease and in facilitating LIN-12/Notch activity. Here, we use genetic methods to explore the relationship between C. elegans LIN-12 and SEL-12 presenilin. Reducing sel-12 activity can suppress the effects of elevated lin-12 activity when LIN-12 is activated by missense mutations but not when LIN-12 is activated by removal of the extracellular and transmembrane domains. These results suggest that SEL-12 does not function downstream of activated LIN-12. An active SEL-12::GFP hybrid protein accumulates in the perinuclear region of the vulval precursor cells (VPCs) of living hermaphrodites, consistent with a localization in endoplasmic reticulum/Golgi membranes; when sel-12 activity is reduced, less LIN-12 protein accumulates in the plasma membranes of the VPCs. Together with the genetic interactions between lin-12 and sel-12, these observations suggest a role for SEL-12 in LIN-12 processing or trafficking. However, SEL-12 does not appear to be a general factor that influences membrane protein activity, since reducing sel-12 activity does not suppress or enhance hypomorphic mutations in other genes encoding membrane proteins. We discuss potential parallels for the role of SEL-12/presenilin in facilitating LIN-12/Notch activity and in amyloid precursor protein (APP) processing.

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