scholarly journals Loss of intermediate regions of perpendicular body axes contributed to miniaturization of tardigrades

2020 ◽  
Vol 287 (1931) ◽  
pp. 20201135
Author(s):  
Mandy Game ◽  
Frank W. Smith
Keyword(s):  
Expression Patterns ◽  
Body Plan ◽  
Intermediate Region ◽  
Expression Domain ◽  
Regulatory Interactions ◽  
Functional Studies ◽  
Gap Genes ◽  
Organ Systems ◽  
Trunk Segments

Tardigrades have a miniaturized body plan. Miniaturization in tardigrades is associated with the loss of several organ systems and an intermediate region of their anteroposterior (AP) axis. However, how miniaturization has affected tardigrade legs is unclear. In arthropods and in onychophorans, the leg gap genes are expressed in regionalized proximodistal (PD) patterns in the legs. Functional studies indicate that these genes regulate growth in their respective expression domains and establish PD identities, partly through mutually antagonistic regulatory interactions. Here, we investigated the expression patterns of tardigrade orthologs of the leg gap genes. Rather than being restricted to a proximal leg region, as in arthropods and onychophorans, we detected coexpression of orthologues of homothorax and extradenticle broadly across the legs of the first three trunk segments in the tardigrade Hypsibius exemplaris . We could not identify a dachshund orthologue in tardigrade genomes, a gene that is expressed in an intermediate region of developing legs in arthropods and onychophorans, suggesting that this gene was lost in the tardigrade lineage. We detected Distal-less expression broadly across all developing leg buds in H. exemplaris embryos, unlike in arthropods and onychophorans, in which it exhibits a distally restricted expression domain. The broad expression patterns of the remaining leg gap genes in H. exemplaris legs may reflect the loss of dachshund and the accompanying loss of an intermediate region of the legs in the tardigrade lineage. We propose that the loss of intermediate regions of both the AP and PD body axes contributed to miniaturization of Tardigrada.

scholarly journals Developmental expression of retinoic acid receptors (RARs)

2009 ◽  
Vol 7 (1) ◽  
pp. nrs.07006 ◽  
Author(s):  
Pascal Dollé
Keyword(s):  
Retinoic Acid ◽  
Receptor Gene ◽  
Expression Patterns ◽  
Dominant Negative ◽  
Receptor Expression ◽  
Retinoic Acid Receptors ◽  
Developmental Expression ◽  
Specific Expression ◽  
Functional Studies ◽  
Organ Systems

Here, I review the developmental expression features of genes encoding the retinoic acid receptors (RARs) and the ‘retinoid X’ or rexinoid receptors (RXRs). The first detailed expression studies were performed in the mouse over two decades ago, following the cloning of the murine Rar genes. These studies revealed complex expression features at all stages of post-implantation development, one receptor gene (Rara) showing widespread expression, the two others (Rarb and Rarg) with highly regionalized and/or cell type-specific expression in both neural and non-neural tissues. Rxr genes also have either widespread (Rxra, Rxrb), or highly-restricted (Rxrg) expression patterns. Studies performed in zebrafish and Xenopus demonstrated expression of Rar and Rxr genes (both maternal and zygotic), at early pre-gastrulation stages. The eventual characterization of specific enzymes involved in the synthesis of retinoic acid (retinol/retinaldehyde dehydrogenases), or the triggering of its catabolism (CYP26 cytochrome P450s), all of them showing differential expression patterns, led to a clearer understanding of the phenomenons regulated by retinoic acid signaling during development. Functional studies involving targeted gene disruptions in the mouse, and additional approaches such as dominant negative receptor expression in other models, have pinpointed the specific, versus partly redundant, roles of the RARs and RXRs in many developing organ systems. These pleiotropic roles are summarized hereafter in relationship to the receptors’ expression patterns.

scholarly journals Expression patterns of signalling molecules and transcription factors in the early rabbit embryo and their significance for modelling amniote axis formation

2021 ◽  
Author(s):  
Ruben Plöger ◽  
Christoph Viebahn
Keyword(s):  
Transcription Factors ◽  
Expression Patterns ◽  
In Situ Hybridisation ◽  
Body Plan ◽  
The Body ◽  
Anchor Point ◽  
Axis Formation ◽  
Point Model ◽  
Signalling Molecules ◽  
Rabbit Embryo

AbstractThe anterior-posterior axis is a central element of the body plan and, during amniote gastrulation, forms through several transient domains with specific morphogenetic activities. In the chick, experimentally proven activity of signalling molecules and transcription factors lead to the concept of a ‘global positioning system’ for initial axis formation whereas in the (mammotypical) rabbit embryo, a series of morphological or molecular domains are part of a putative ‘three-anchor-point model’. Because circular expression patterns of genes involved in axis formation exist in both amniote groups prior to, and during, gastrulation and may thus be suited to reconcile these models, the expression patterns of selected genes known in the chick, namely the ones coding for the transcription factors eomes and tbx6, the signalling molecule wnt3 and the wnt inhibitor pkdcc, were analysed in the rabbit embryonic disc using in situ hybridisation and placing emphasis on their germ layer location. Peripheral wnt3 and eomes expression in all layers is found initially to be complementary to central pkdcc expression in the hypoblast during early axis formation. Pkdcc then appears — together with a posterior-anterior gradient in wnt3 and eomes domains — in the epiblast posteriorly before the emerging primitive streak is marked by pkdcc and tbx6 at its anterior and posterior extremities, respectively. Conserved circular expression patterns deduced from some of this data may point to shared mechanisms in amniote axis formation while the reshaping of localised gene expression patterns is discussed as part of the ‘three-anchor-point model’ for establishing the mammalian body plan.

scholarly journals Phylogenetic comparison and splice site conservation of eukaryotic U1 snRNP-specific U1-70K gene family

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tao Fan ◽  
Yu-Zhen Zhao ◽  
Jing-Fang Yang ◽  
Qin-Lai Liu ◽  
Yuan Tian ◽  
...  
Keyword(s):  
Gene Family ◽  
Splice Site ◽  
Messenger Rna ◽  
Expression Patterns ◽  
Protein Structures ◽  
Single Copy ◽  
Central Component ◽  
Animal Kingdom ◽  
Functional Studies ◽  
U1 Snrnp

AbstractEukaryotic cells can expand their coding ability by using their splicing machinery, spliceosome, to process precursor mRNA (pre-mRNA) into mature messenger RNA. The mega-macromolecular spliceosome contains multiple subcomplexes, referred to as small nuclear ribonucleoproteins (snRNPs). Among these, U1 snRNP and its central component, U1-70K, are crucial for splice site recognition during early spliceosome assembly. The human U1-70K has been linked to several types of human autoimmune and neurodegenerative diseases. However, its phylogenetic relationship has been seldom reported. To this end, we carried out a systemic analysis of 95 animal U1-70K genes and compare these proteins to their yeast and plant counterparts. Analysis of their gene and protein structures, expression patterns and splicing conservation suggest that animal U1-70Ks are conserved in their molecular function, and may play essential role in cancers and juvenile development. In particular, animal U1-70Ks display unique characteristics of single copy number and a splicing isoform with truncated C-terminal, suggesting the specific role of these U1-70Ks in animal kingdom. In summary, our results provide phylogenetic overview of U1-70K gene family in vertebrates. In silico analyses conducted in this work will act as a reference for future functional studies of this crucial U1 splicing factor in animal kingdom.

scholarly journals Modeling a gene regulatory network of EMT hybrid states for mouse embryonic skin cells

2019 ◽  
Author(s):  
Dan Ramirez ◽  
Vivek Kohar ◽  
Ataur Katebi ◽  
Mingyang Lu
Keyword(s):  
Gene Regulatory Network ◽  
Regulatory Network ◽  
Epithelial Mesenchymal Transition ◽  
Expression Patterns ◽  
Mesenchymal Transition ◽  
Hybrid State ◽  
Regulatory Interactions ◽  
Skin Cells ◽  
Embryonic Skin ◽  
Gene Regulatory

AbstractEpithelial-mesenchymal transition (EMT) plays a crucial role in embryonic development and tumorigenesis. Although EMT has been extensively studied with both computational and experimental methods, the gene regulatory mechanisms governing the transition are not yet well understood. Recent investigations have begun to better characterize the complex phenotypic plasticity underlying EMT using a computational systems biology approach. Here, we analyzed recently published single-cell RNA sequencing data from E9.5 to E11.5 mouse embryonic skin cells and identified the gene expression patterns of both epithelial and mesenchymal phenotypes, as well as a clear hybrid state. By integrating the scRNA-seq data and gene regulatory interactions from the literature, we constructed a gene regulatory network model governing the decision-making of EMT in the context of the developing mouse embryo. We simulated the network using a recently developed mathematical modeling method, named RACIPE, and observed three distinct phenotypic states whose gene expression patterns can be associated with the epithelial, hybrid, and mesenchymal states in the scRNA-seq data. Additionally, the model is in agreement with published results on the composition of EMT phenotypes and regulatory networks. We identified Wnt signaling as a major pathway in inducing the EMT and its role in driving cellular state transitions during embryonic development. Our findings demonstrate a new method of identifying and incorporating tissue-specific regulatory interactions into gene regulatory network modeling.Author SummaryEpithelial-mesenchymal transition (EMT) is a cellular process wherein cells become disconnected from their surroundings and acquire the ability to migrate through the body. EMT has been observed in biological contexts including development, wound healing, and cancer, yet the regulatory mechanisms underlying it are not well understood. Of particular interest is a purported hybrid state, in which cells can retain some adhesion to their surroundings but also show mesenchymal traits. Here, we examine the prevalence and composition of the hybrid state in the context of the embryonic mouse, integrating gene regulatory interactions from published experimental results as well as from the specific single cell RNA sequencing dataset of interest. Using mathematical modeling, we simulated a regulatory network based on these sources and aligned the simulated phenotypes with those in the data. We identified a hybrid EMT phenotype and revealed the inducing effect of Wnt signaling on EMT in this context. Our regulatory network construction process can be applied beyond EMT to illuminate the behavior of any biological phenomenon occurring in a specific context, allowing better identification of therapeutic targets and further research directions.

scholarly journals Genome-Wide Identification and Characterization of theLRR-RLKGene Family in TwoVerniciaSpecies

2015 ◽  
Vol 2015 ◽  
pp. 1-17 ◽  
Author(s):  
Huiping Zhu ◽  
Yangdong Wang ◽  
Hengfu Yin ◽  
Ming Gao ◽  
Qiyan Zhang ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Consensus Sequence ◽  
Expression Patterns ◽  
Functional Studies ◽  
Industrial Oil ◽  
Extensive Evaluation ◽  
Genome Wide ◽  
Pathogen Response ◽  
Lrr Domain

Leucine-rich repeat receptor-like kinases (LRR-RLKs) make up the largest group of RLKs in plants and play important roles in many key biological processes such as pathogen response and signal transduction. To date, most studies on LRR-RLKs have been conducted on model plants. Here, we identified 236 and 230LRR-RLKsin two industrial oil-producing trees:Vernicia fordiiandVernicia montana, respectively. Sequence alignment analyses showed that the homology of the RLK domain (23.81%) was greater than that of the LRR domain (9.51%) among theVf/VmLRR-RLKs. The conserved motif of the LRR domain inVf/VmLRR-RLKsmatched well the known plant LRR consensus sequence but differed at the third last amino acid (W or L). Phylogenetic analysis revealed thatVf/VmLRR-RLKswere grouped into 16 subclades. We characterized the expression profiles ofVf/VmLRR-RLKsin various tissue types including root, leaf, petal, and kernel. Further investigation revealed thatVf/VmLRR-RLKorthologous genes mainly showed similar expression patterns in response to tree wilt disease, except 4 pairs ofVf/VmLRR-RLKsthat showed opposite expression trends. These results represent an extensive evaluation ofLRR-RLKsin two industrial oil trees and will be useful for further functional studies on these proteins.

A genetic link between Tbx1 and fibroblast growth factor signaling

Development ◽  
2002 ◽  
Vol 129 (19) ◽  
pp. 4605-4611 ◽  
Author(s):  
Francesca Vitelli ◽  
Ilaria Taddei ◽  
Masae Morishima ◽  
Erik N. Meyers ◽  
Elizabeth A. Lindsay ◽  
...  
Keyword(s):  
Aortic Arch ◽  
Expression Patterns ◽  
Pharyngeal Arch ◽  
Growth Factor Signaling ◽  
Expression Domain ◽  
Primary Defect ◽  
Genetic Link ◽  
Pharyngeal Endoderm ◽  
Pharyngeal Arch Arteries ◽  
Tbx1 Haploinsufficiency

Tbx1 haploinsufficiency causes aortic arch abnormalities in mice because of early growth and remodeling defects of the fourth pharyngeal arch arteries. The function of Tbx1 in the development of these arteries is probably cell non-autonomous, as the gene is not expressed in structural components of the artery but in the surrounding pharyngeal endoderm. We hypothesized that Tbx1 may trigger signals from the pharyngeal endoderm directed to the underlying mesenchyme. We show that the expression patterns of Fgf8 and Fgf10, which partially overlap with Tbx1 expression pattern, are altered in Tbx1–/– mutants. In particular, Fgf8 expression is abolished in the pharyngeal endoderm. To understand the significance of this finding for the pathogenesis of the mutant Tbx1 phenotype, we crossed Tbx1 and Fgf8 mutants. Double heterozygous Tbx1+/–;Fgf8+/– mutants present with a significantly higher penetrance of aortic arch artery defects than do Tbx1+/–;Fgf8+/+ mutants, while Tbx1+/+;Fgf8+/– animals are normal. We found that Fgf8 mutation increases the severity of the primary defect caused by Tbx1 haploinsufficiency, i.e. early hypoplasia of the fourth pharyngeal arch arteries, consistent with the time and location of the shared expression domain of the two genes. Hence, Tbx1 and Fgf8 interact genetically in the development of the aortic arch. Our data provide the first evidence of a genetic link between Tbx1 and FGF signaling, and the first example of a modifier of the Tbx1 haploinsufficiency phenotype. We speculate that the FGF8 locus might affect the penetrance of cardiovascular defects in individuals with chromosome 22q11 deletions involving TBX1.

Abstract P104: Reactivation of Embryonic Gene Program due to CUG Repeat RNA Expression in Myotonic Dystrophy

2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Auinash Kalsotra ◽  
Ravi Singh ◽  
Chad Creighton ◽  
Thomas Cooper
Keyword(s):  
Gene Expression ◽  
Myotonic Dystrophy ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Expression Patterns ◽  
Causative Mutation ◽  
Inherited Disease ◽  
Aberrant Expression ◽  
Organ Systems ◽  
General Response

Myotonic dystrophy type 1 (DM1) is a dominantly inherited disease that affects multiple organ systems. Cardiac involvement, which is characterized by conduction defects and arrhythmias, is the second leading cause of death in DM1 patients. The causative mutation is a CTG expansion in the 3' untranslated region of DMPK gene resulting in aberrant expression of CUG repeat RNA that accumulates into nuclear foci and causes misregulation in alternative splicing. Here we show that heart-specific and inducible expression of CUG repeat RNA in a DM1 mouse model results in global reactivation of embryonic gene expression program in adult heart that is distinct from a general hypertrophic stress response. Using q-PCR TaqMan arrays, we identified 54 miRNAs that were differentially expressed in DM1 mouse hearts one week following induction of CUG repeat RNA. Interestingly, 83% (45/54) of them exhibited a developmental shift in expression towards the embryonic pattern. Because over 90% (41/45) of them were down regulated within 72 hr after induction of repeat RNA and only 2/22 examined decreased in two unrelated mouse models of heart disease, we conclude their reduced expression is specific to DM1 and not simply a general response to cardiac injury. Microarray studies revealed a developmental switch not only in the miRNA expression patterns but also a pervasive shift in mRNA steady state levels of a number of genes to embryonic stage. Intriguingly, we found that loss of MBNL1 or gain of CELF1 activity, two major RNA binding proteins disrupted in DM1, are not driving the miRNA misregulation since their expression is indistinguishable between wild type, MBNL1 knock out and CELF1 over expressing mice. Moreover, comparable decrease in ten out of ten primary miRNA transcripts examined suggests loss of expression is not due to a processing defect. Instead, we discovered that adult-to-embryonic shift in expression of select micro- and messenger RNAs in DM1 heart occurs due to specific inactivation of a Mef2 transcriptional program. We are currently determining causal contributions of this Mef2-miRNA circuitry in the developmental reprogramming of gene expression in DM1 as well as its direct role in cardiac manifestations of this disease.

Cross-regulatory interactions among the gap genes of Drosophila

Nature ◽  
1986 ◽  
Vol 324 (6098) ◽  
pp. 668-670 ◽  
Author(s):  
Herbert Jäckle ◽  
Diethard Tautz ◽  
Reinhard Schuh ◽  
Eveline Seifert ◽  
Ruth Lehmann
Keyword(s):  
Regulatory Interactions ◽  
Gap Genes

scholarly journals Genome-Wide Investigation of the NAC Gene Family and Its Potential Association with the Secondary Cell Wall in Moso Bamboo

Biomolecules ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 609 ◽  
Author(s):  
Shan ◽  
Yang ◽  
Xu ◽  
Zhu ◽  
Gao
Keyword(s):  
Cell Wall ◽  
Gene Family ◽  
Secondary Cell Wall ◽  
Expression Patterns ◽  
Wood Property ◽  
Moso Bamboo ◽  
Functional Studies ◽  
Bamboo Shoots ◽  
Potential Association ◽  
Nac Gene Family

NAC (NAM, ATAF, and CUC) transcription factors (TFs) are implicated in the transcriptional regulation of diverse processes and have been characterized in a number of plant species. However, NAC TFs are still not well understood in bamboo, especially their potential association with the secondary cell wall (SCW). Here, 94 PeNACs were identified and characterized in moso bamboo (Phyllostachys edulis). Based on their gene structures and conserved motifs, the PeNACs were divided into 11 groups according to their homologs in Arabidopsis. PeNACs were expressed variously in different tissues of moso bamboo, suggesting their functional diversity. Fifteen PeNACs associated with the SCW were selected for co-expression analysis and validation. It was predicted that 396 genes were co-expressed with the 15 PeNACs, in which 16 and 55 genes were involved in the lignin catabolic process and cellulose biosynthetic process respectively. As the degree of lignification in the growing bamboo shoots increased, all 15 PeNACs were upregulated with a trend of rising first and then decreasing except PeNAC37, which increased continuously. These results indicated that these PeNACs might play important roles in SCW biosynthesis and lignification in bamboo shoots. Seven of 15 PeNACs had been found positively co-expressed with seven PeMYBs, and they had similar expression patterns with those of the PeMYBs in bamboo shoots. The targeted sites of miR164 were found in 16 PeNACs, of which three PeNACs associated with SCW were validated to have an opposite expression trend to that of miR164 in growing bamboo shoots. In addition, three PeNACs were selected and verified to have self-activation activities. These results provide comprehensive information of the NAC gene family in moso bamboo, which will be helpful for further functional studies of PeNACs to reveal the molecular regulatory mechanisms of bamboo wood property.

scholarly journals Genome-wide identification and expression analysis of SWEET gene family in Litchi chinensis reveal the involvement of LcSWEET2a/3b in early seed development

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Hanhan Xie ◽  
Dan Wang ◽  
Yaqi Qin ◽  
Anna Ma ◽  
Jiaxin Fu ◽  
...  
Keyword(s):  
Gene Family ◽  
Seed Development ◽  
Expression Patterns ◽  
Phloem Loading ◽  
Reproductive Organs ◽  
Phylogenetic Tree Analysis ◽  
Multiple Sequence ◽  
Litchi Chinensis ◽  
Functional Studies ◽  
Early Seed Development

Abstract Background SWEETs (Sugar Will Eventually be Exported transporters) function as sugar efflux transporters that perform diverse physiological functions, including phloem loading, nectar secretion, seed filling, and pathogen nutrition. The SWEET gene family has been identified and characterized in a number of plant species, but little is known about in Litchi chinensis, which is an important evergreen fruit crop. Results In this study, 16 LcSWEET genes were identified and nominated according to its homologous genes in Arabidopsis and grapevine. Multiple sequence alignment showed that the 7 alpha-helical transmembrane domains (7-TMs) were basically conserved in LcSWEETs. The LcSWEETs were divided into four clades (Clade I to Clade IV) by phylogenetic tree analysis. A total of 8 predicted motifs were detected in the litchi LcSWEET genes. The 16 LcSWEET genes were unevenly distributed in 9 chromosomes and there was one pairs of segmental duplicated events by synteny analysis. The expression patterns of the 16 LcSWEET genes showed higher expression levels in reproductive organs. The temporal and spatial expression patterns of LcSWEET2a and LcSWEET3b indicated they play central roles during early seed development. Conclusions The litchi genome contained 16 SWEET genes, and most of the genes were expressed in different tissues. Gene expression suggested that LcSWEETs played important roles in the growth and development of litchi fruits. Genes that regulate early seed development were preliminarily identified. This work provides a comprehensive understanding of the SWEET gene family in litchi, laying a strong foundation for further functional studies of LcSWEET genes and improvement of litchi fruits.

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