scholarly journals Convergent evolution of pregnancy-specific glycoproteins in human and horse

Reproduction ◽  
2016 ◽  
pp. 171-184 ◽  
Author(s):  
Denis Aleksic ◽  
Lisa Blaschke ◽  
Sophie Mißbach ◽  
Jana Hänske ◽  
Wiebke Weiß ◽  
...  
Keyword(s):  
Immune Cells ◽  
Convergent Evolution ◽  
Cell Adhesion Molecule ◽  
Close Contact ◽  
Phylogenetic Analyses ◽  
Functional Assay ◽  
Trophoblast Cells ◽  
Similar Activity ◽  
Non Invasive ◽  
Fibrinogen Binding

Pregnancy-specific glycoproteins (PSGs) are members of the carcinoembryonic antigen cell adhesion molecule (CEACAM) family that are secreted by trophoblast cells. PSGs may modulate immune, angiogenic and platelet responses during pregnancy. Until now, PSGs are only found in species that have a highly invasive (hemochorial) placentation including humans, mice and rats. Surprisingly, analyzing the CEACAM gene family of the horse, which has a non-invasive epitheliochorial placenta, with the exception of the transient endometrial cups, we identified equine CEACAM family members that seem to be related to PSGs of rodents and primates. We identified seven genes that encode secreted PSG-like CEACAMs. Phylogenetic analyses indicate that they evolved independently from an equine CEACAM1-like ancestor rather than from a common PSG-like ancestor with rodents and primates. Significantly, expression of PSG-like genes (CEACAM44, CEACAM48, CEACAM49 and CEACAM55) was found in non-invasive as well as invasive trophoblast cells such as purified chorionic girdle cells and endometrial cup cells. Chorionic girdle cells are highly invasive trophoblast cells that invade the endometrium of the mare where they form endometrial cups and are in close contact with maternal immune cells. Therefore, the microenvironment of invasive equine trophoblast cells has striking similarities to the microenvironment of trophoblast cells in hemochorial placentas, suggesting that equine PSG-like CEACAMs and rodent and primate PSGs have undergone convergent evolution. This is supported by our finding that equine PSG-like CEACAM49 exhibits similar activity to certain rodent and human PSGs in a functional assay of platelet–fibrinogen binding. Our results have implications for understanding the evolution of PSGs and their functions in maternal–fetal interactions.

scholarly journals Fetomaternal interactions and influences during equine pregnancy

Reproduction ◽  
2001 ◽  
pp. 513-527 ◽  
Author(s):  
WR Allen
Keyword(s):  
Steroid Hormones ◽  
Adrenal Glands ◽  
Maternal Serum ◽  
Trophoblast Cells ◽  
Maternal Circulation ◽  
Invasive Phenotype ◽  
Uterine Lumen ◽  
Non Invasive ◽  
Unusual Phenomenon ◽  
Near Term

The equine embryo takes 6 days to traverse the oviduct and, when it finally enters the uterus, it remains spherical in shape and moves continually throughout the uterine lumen until day 17 after ovulation to deliver its maternal recognition of pregnancy signal to the entire endometrium. Between day 25 and day 35 after ovulation, the trophoblast cells of a discrete annulate portion of the chorion multiply rapidly and acquire an invasive phenotype and, between day 36 and day 38, migrate deeply into the maternal endometrium to form the equine-unique endometrial protuberances known as endometrial cups. These cups secrete large quantities of a gonadotrophic hormone (eCG) into the maternal circulation which, in conjunction with pituitary FSH, stimulates the development of accessory luteal structures in the maternal ovaries to supplement the supply of progesterone to maintain the pregnancy until the placenta can assume this role at about day 100. The non-invasive allantochorion extends slowly to fill the uterus by days 80-85 and its microcotyledonary architecture, which provides both haemotrophic and histotrophic nutrition for the growing fetus, is not fully established until days 120-140. The fetoplacental unit synthesizes large quantities of steroid hormones during the second half of pregnancy, using fetal C-19 precursors secreted by the enlarged fetal gonads for the production of oestrogens and maternal C-21 precursors for the synthesis of progesterone and large quantities of 5alpha-reduced progestagens. Near term, additional pregnenelone is secreted by the fetal adrenal glands so that the mare exhibits the unusual phenomenon of foaling while maternal serum progestagen concentrations are increasing and oestrogen concentrations are decreasing.

Adaptive convergent evolution of genome proofreading in SARS-CoV2: insights into the Eigen’s paradox

2021 ◽  
Author(s):  
Keerthic Aswin ◽  
Srinivasan Ramachandran ◽  
Vivek T Natarajan
Keyword(s):  
Convergent Evolution ◽  
Genome Stability ◽  
Evolutionary History ◽  
Rna Binding ◽  
Phylogenetic Analyses ◽  
Comparative Genome Analysis ◽  
The Family ◽  
History Of ◽  
Key Residues

AbstractEvolutionary history of coronaviruses holds the key to understand mutational behavior and prepare for possible future outbreaks. By performing comparative genome analysis of nidovirales that contain the family of coronaviruses, we traced the origin of proofreading, surprisingly to the eukaryotic antiviral component ZNFX1. This common recent ancestor contributes two zinc finger (ZnF) motifs that are unique to viral exonuclease, segregating them from DNA proof-readers. Phylogenetic analyses indicate that following acquisition, genomes of coronaviruses retained and further fine-tuned proofreading exonuclease, whereas related families harbor substitution of key residues in ZnF1 motif concomitant to a reduction in their genome sizes. Structural modelling followed by simulation suggests the role of ZnF in RNA binding. Key ZnF residues strongly coevolve with replicase, and the helicase involved in duplex RNA unwinding. Hence, fidelity of replication in coronaviruses is a result of convergent evolution, that enables maintenance of genome stability akin to cellular proofreading systems.

Mycena turandotiana, Mycena fengguan, and Mycena brunneisetosa – Two new species and one new record of spinose Mycena from Taiwan

Nova Hedwigia ◽  
2020 ◽  
Vol 111 (1) ◽  
pp. 87-100
Author(s):  
Chiung-Chih Chang ◽  
Chi-Yu Chen ◽  
Wen-Wen Lin ◽  
Yu-Shen Shih ◽  
Hsiao-Wei Kao
Keyword(s):  
New Species ◽  
Convergent Evolution ◽  
New Record ◽  
Phylogenetic Analyses ◽  
Two New Species ◽  
Thin Walled

Two new species and one new record of spinose Mycena were discovered in Taiwan. They are characterized by the presence of unicellular and erect spinose pilesetae on the surface of the pileipellis. The two new species (M. turandotiana and M. fengguan) have pileocystidia originating from hyphae of the pileipellis and thin-walled pileocystidia, while the new record (M. brunneisetosa) has thick-walled pileocystidia. Phylogenetic analyses suggest that the spinose structures in these Mycena resulted from convergent evolution.

Pharmacotherapeuetic Options for the Treatment of Multiple Sclerosis

2012 ◽  
Vol 4 ◽  
pp. CMT.S8661 ◽  
Author(s):  
Alan M. Palmer
Keyword(s):  
Multiple Sclerosis ◽  
Immune Cells ◽  
Cell Adhesion Molecule ◽  
Major Change ◽  
Clinical Development ◽  
Immunomodulatory Drugs ◽  
Amino Acid Peptide ◽  
A Cell ◽  
Patent Life ◽  
Neuro Inflammation

Multiple sclerosis is the most common progressive and disabling neurological condition in young adults. Neuro-inflammation is an early and persistent change and forms the basis of most pharmacotherapy for this disease. Immunomodulatory drugs are mainly biologies (β-interferons, a four amino acid peptide, and a monoclonal antibody to a cell adhesion molecule on the blood-CNS barrier) that either attenuate the inflammatory response or block the movement of immune cells into the CNS. They reduce the rate of relapse, but have little or no effect on the progression of disability. The market landscape for MS drugs is in the midst of major change because the patent life of many of these medicines will soon expire, which will lead to the emergence of biosimilars. In addition, new small molecule immunomodulatory and palliative drugs have entered the market, with more in the pipeline; a number of monoclonal antibodies and other immunomodulatory drugs are also in clinical development.

scholarly journals Bat echolocation calls: adaptation and convergent evolution

2007 ◽  
Vol 274 (1612) ◽  
pp. 905-912 ◽  
Author(s):  
Gareth Jones ◽  
Marc W Holderied
Keyword(s):  
Convergent Evolution ◽  
Laser Scanning ◽  
Phylogenetic Analyses ◽  
Pulse Interval ◽  
Dependent Manner ◽  
Echolocation Calls ◽  
Habitat Features ◽  
Call Structure ◽  
Evolution By Natural Selection ◽  
Natural Selection Theory

Bat echolocation calls provide remarkable examples of ‘good design’ through evolution by natural selection. Theory developed from acoustics and sonar engineering permits a strong predictive basis for understanding echolocation performance. Call features, such as frequency, bandwidth, duration and pulse interval are all related to ecological niche. Recent technological breakthroughs have aided our understanding of adaptive aspects of call design in free-living bats. Stereo videogrammetry, laser scanning of habitat features and acoustic flight path tracking permit reconstruction of the flight paths of echolocating bats relative to obstacles and prey in nature. These methods show that echolocation calls are among the most intense airborne vocalizations produced by animals. Acoustic tracking has clarified how and why bats vary call structure in relation to flight speed. Bats using broadband echolocation calls adjust call design in a range-dependent manner so that nearby obstacles are localized accurately. Recent phylogenetic analyses based on gene sequences show that particular types of echolocation signals have evolved independently in several lineages of bats. Call design is often influenced more by perceptual challenges imposed by the environment than by phylogeny, and provides excellent examples of convergent evolution. Now that whole genome sequences of bats are imminent, understanding the functional genomics of echolocation will become a major challenge.

Non-Invasive Multi-Dimensional Two-Photon Microscopy enables optical fingerprinting (TPOF) of immune cells

2014 ◽  
Vol 8 (6) ◽  
pp. 466-479 ◽  
Author(s):  
Uta Gehlsen ◽  
Marta Szaszák ◽  
Andreas Gebert ◽  
Norbert Koop ◽  
Gereon Hüttmann ◽  
...  
Keyword(s):  
Immune Cells ◽  
Two Photon Microscopy ◽  
Two Photon ◽  
Non Invasive

scholarly journals Phylogenetic analysis of Andinia (Pleurothallidinae; Orchidaceae) and a systematic re-circumscription of the genus

Phytotaxa ◽  
2017 ◽  
Vol 295 (2) ◽  
pp. 101 ◽  
Author(s):  
MARK WILSON ◽  
GRAHAM S. FRANK ◽  
LOU JOST ◽  
ALEC M. PRIDGEON ◽  
SEBASTIAN VIEIRA-URIBE ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Convergent Evolution ◽  
Type Species ◽  
Floral Morphology ◽  
Phylogenetic Analyses ◽  
Evolutionary Diversification ◽  
The Andes ◽  
Deceit Pollination ◽  
Nuclear Its ◽  
The Individual

Most of the species studied in this paper have previously been placed in either Pleurothallis or Lepanthes. However, at one time or another, members of the group have also been placed in the genera Andinia, Brachycladium, Lueranthos, Masdevalliantha, Neooreophilus, Oreophilus, Penducella, Salpistele and Xenosia. Phylogenetic analyses of nuclear ITS and plastid matK sequences indicate that these species form a strongly supported clade that is only distantly related to Lepanthes and is distinct from Pleurothallis and Salpistele. Since this clade includes the type species of Andinia, A. dielsii, and it has taxonomic precedence over all other generic names belonging to this group, Andinia is re-circumscribed and expanded to include 72 species segregated into five subgenera: Aenigma, Andinia, Brachycladium, Masdevalliantha and Minuscula. The required taxonomic transfers are made herein. We hypothesize that convergent evolution towards a similar pollinator syndrome involving deceit pollination via pseudocopulation by Diptera resulted in a similar floral morphology between species of subgenus Brachycladium and species of Lepanthes; hence the prior placement of the species of subgenus Brachycladium in Lepanthes. Species of the re-circumscribed Andinia are confined exclusively to the Andes, ranging from about 1,200 to 3,800 m, from Colombia south to Bolivia, making the generic name very apt. Elevational distributions of the individual clades are discussed in relation to the possible evolutionary diversification of the most species-rich clade, subgenus Brachycladium.

scholarly journals Identification and characterization of zebrafish Tlr4 co-receptor Md-2

2019 ◽  
Author(s):  
Andrea N. Loes ◽  
Melissa N. Hinman ◽  
Dylan R. Farnsworth ◽  
Adam C. Miller ◽  
Karen Guillemin ◽  
...  
Keyword(s):  
Immune Cells ◽  
De Novo ◽  
Model Organism ◽  
Innate Immune ◽  
Functional Assay ◽  
Innate Immune Cells ◽  
Apparent Difference ◽  
Loss Of Function ◽  
Genomic Context ◽  
Specific Subset

ABSTRACTThe zebrafish (Danio rerio) is a powerful model organism for studies of the innate immune system. One apparent difference between human and zebrafish innate immunity is the cellular machinery for LPS-sensing. In amniotes, the protein complex formed by Toll-like receptor 4 and myeloid differentiation factor 2 (Tlr4/Md-2) recognizes the bacterial molecule lipopolysaccharide (LPS) and triggers an inflammatory response. It is believed that zebrafish have neither Md-2 nor Tlr4: Md-2 has not been identified outside of amniotes, while the zebrafish tlr4 genes appear to be paralogs, not orthologs, of amniote TLR4s. We revisited these conclusions. We identified a zebrafish gene encoding Md-2, ly96. Using single-cell RNA-Seq, we found that ly96 is transcribed in cells that also transcribe genes diagnostic for innate immune cells, including the zebrafish tlr4-like genes. Unlike amniote LY96, zebrafish ly96 expression is restricted to a small number of macrophage-like cells. In a functional assay, zebrafish Md-2 and Tlr4a form a complex that activates NF-κB signaling in response to LPS, but ly96 loss-of-function mutations gave little protection against LPS-toxicity in larval zebrafish. Finally, by analyzing the genomic context of tlr4 genes in eleven jawed vertebrates, we found that tlr4 arose prior to the divergence of teleosts and tetrapods. Thus, an LPS-sensitive Tlr4/Md-2 complex is likely an ancestral feature shared by mammals and zebrafish, rather than a de novo invention on the tetrapod lineage. We hypothesize that zebrafish retain an ancestral, low-sensitivity Tlr4/Md-2 complex that confers LPS-responsiveness to a specific subset of innate immune cells.

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