What makes an animal? The molecular quest for the origin of the Animal Kingdom

Synopsis

What makes an animal? To find the answer we need to integrate data from disciplines such as phylogenetics, palaeontology, ecology, development, anatomy and physiology, as well as molecular biology and genomics. Knowledge of which groups branched before and after the origin of animals is essential. Recent advances in molecular phylogenetics, together with the discovery of new eukaryotic lineages, have drawn a new picture of the ancestry of animals. The nature of the early diverging animal lineages and the timing of the transition are in a state of flux. Various factors have been linked to this striking transition to multicellularity, including changes in environmental conditions and the ecological interactions between unicellular eukaryotes. The current wealth of genomic data has also shed new light on this question. The analysis of the genome of various close relatives of animals has revealed the importance that recycling of ancient genes into metazoan biological functions played into animal origins. A recent study reconstructing the genome of the last common ancestor of extant animals has unveiled an unprecedented emergence of new genes, highlighting the role of genomic novelty in the origin of metazoans.

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Insights into electroreceptor development and evolution from molecular comparisons with hair cells

Synopsis

The vertebrate lateral line system comprises a mechanosensory division, with neuromasts containing hair cells that detect local water movement ("distant touch"); and an electrosensory division, with electrosensory organs that detect the weak, low-frequency electric fields surrounding other animals in water (primarily used for hunting). The entire lateral line system was lost in the amniote lineage with the transition to fully terrestrial life; the electrosensory division was lost independently in several lineages, including the ancestors of frogs and of teleost fishes. (Electroreception with different characteristics subsequently evolved independently within two teleost lineages.) Recent gene expression studies in a non-teleost actinopterygian fish suggest that electroreceptor ribbon synapses employ the same transmission mechanisms as hair cell ribbon synapses, and show that developing electrosensory organs express transcription factors essential for hair cell development, including Atoh1 and Pou4f3. Previous hypotheses for electroreceptor evolution suggest either that electroreceptors and hair cells evolved independently in the vertebrate ancestor from a common ciliated secondary cell, or that electroreceptors evolved from hair cells. The close developmental and putative physiological similarities implied by the gene expression data support the latter hypothesis, i.e., that electroreceptors evolved in the vertebrate ancestor as a "sister cell-type" to lateral line hair cells.

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Reactive Astrogliosis in an Experimental Model of Fibromyalgia: Effect of Dexmedetomidine

To our knowledge, this is the first study which investigates the induction of neuroinflammation in rats using an acidic-saline model of fibromyalgia. It is well known that the hippocampus has a fundamental role in pain perception, and astrocytes play a crucial role in pain signaling. Our aim is to evaluate the ability of dexmedetomidine to attenuate the inflammatory responses induced in astrocytes. In a group of healthy rats, induction of chronic muscle pain by intramuscular injection of 100 µL of acidic saline on days 0 and 5 resulted in peripheral sensitization (measured using the von Frey test) and significant (p #x3c; 0.05) increases in IL-1β (160.2 ± 1.1 to 335.2 ± 1.8), IL-6 (100.1 ± 1.4 to 202.4 ± 1.1), and TNF-α (60.0 ± 0.7 to 115.5 ± 1). Light and electron microscopy revealed degenerative changes in the hippocampus and reactive astrogliosis. Immunohistochemistry showed increased expression of glial fibrillary acid protein and inducible nitric oxide synthase. Surprisingly, treatment with a single dose of an α₂-adrenergic agonist, dexmedetomidine (5 µg/kg i.p.), attenuated these changes. This trial suggests that dexmedetomidine possibly directly acts on astrocytes, and a peripheral action is also suggested.
Cells Tissues Organs

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Genetic Polymorphism Study on Aedes albopictus of Different Geographical Regions Based on DNA Barcoding

Aedes albopictus is a very important vector for pathogens of many infectious diseases including dengue fever. In this study, we explored the genetic polymorphism of Aedes albopictus strains in different geographical regions using DNA barcoding of mitochondrial COI (MT-COI) gene. We collected MT-COI sequence of 106 Aedes albopictus mosquitos from 6 provinces in China including Fujian, Guangdong, Hainan, Yunnan, and Taiwan. The length of the sequences is 709bp with the content of A+T (67.7%) greater than that of G+C (32.3%). We identified mutations in 90 (13.68%) loci, of which 57 (63.33%) are transitions, 28 (31.11%) are transversions, and 5 (5.56%) are hypervariable loci. In addition, we obtained 42 haplotypes, 4 (9.52%) of which are shared among different populations. The haplotype diversity of Aedes albopictus is 0.882 and nucleotide diversity is 0.01017. Moreover, the pedigree network diagram shows that most haplotypes are under parallel evolution, suggesting a local expansion of Aedes albopictus in history. Finally, the Neighbor-Joining tree of MT-COI haplotypes reveals a certain correlation between haplotype clusters and geographical distribution, and there are differences among Aedes albopictus in different geographical regions. In conclusion, DNA barcoding of MT-COI gene is an effective method to study the genetic structure of Aedes albopictus.

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Advantages of Graphene Biosensors for Human Stem Cell Therapy Potency Assays

Regenerative medicine is challenged by the need to conform to rigorous guidelines for establishing safe and effective development and translation of stem cell-based therapies. Counteracting widespread concerns regarding unproven cell therapies, stringent cell-based assays seek not only to avoid harm but also to enhance quality and efficacy. Potency indicates that the cells are functionally fit for purpose before they are administered to the patient. It is a paramount quantitative critical quality attribute serving as a decisive release criterion. Given a broad range of stem cell types and therapeutic contexts the potency assay often comprises one of the most demanding hurdles for release of a cell therapy medicinal product. With need for improved biomarker assessment and expedited measurement, recent advances in graphene-based biosensors suggest that they are poised to be valuable platforms for accelerating potency assay development. Among several potential advantages, they offer versatility for sensitive measurement of a broad range of potential biomarker types, cell biocompatibility for direct measurement, and small sample sufficiency, plus ease of use and point-of-care applicability.

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A Multicenter, Randomized, Controlled Trial of Electroacupuncture for Perimenopause Women with Mild-Moderate Depression

Objective. Up to 62% of perimenopausal women have depression symptoms. However, there is no efficacy treatment. The aim of this study is to compare the clinical efficacy and safety of EA therapy and escitalopram on perimenopause women with mild-moderate depressive symptom. Method. A multicenter, randomized, positive-controlled clinical trial was conducted at 6 hospitals in China. 242 perimenopause women with mild-moderate depressive symptom were recruited and randomly assigned to receive 36 sessions of EA treatment or escitalopram treatment. The primary outcome measure was the 17-item Hamilton Depression Rating Scale (HAMD-17). The secondary outcome measures include menopause-specific quality of life (MENQOL) and serum sexual hormones which include estrogen, follicle-stimulating hormone, and luteinizing hormone. Results. 221 (91.3%) completed the study, including 116 in the EA group and 105 in the escitalopram group. The baseline levels of demographic and outcome measurements were similar in the two groups. In the intervention period, there was no difference between two groups. However, in the follow-up, both HAMD-17 and MENQOL were significantly decreased, and at week 24 the mean differences were −2.23 and −8.97, respectively. There were no significant differences in the change of serum sexual hormones between the two groups. No serious adverse events occurred. Conclusion. EA treatment is effective and safe in relieving depression symptom and improving the quality of life in the perimenopausal depression. Further research is needed to understand long-term efficacy and explore the mechanism of this intervention. This study is registered with ClinicalTrials.gov NCT02423694.

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Isolation of a Reassortant H1N2 Swine Flu Strain of Type “Swine-Human-Avian” and Its Genetic Variability Analysis

We isolated an influenza strain named A/Swine/Fujian/F1/2010 (H1N2) from a pig suspected to be infected with swine flu. The results of electron microscopy, hemagglutination (HA) assay, hemagglutination inhibition (HI) assay, and whole genome sequencing analysis suggest that it was a reassortant virus of swine (H1N1 subtype), human (H3N2 subtype), and avian influenza viruses. To further study the genetic evolution of A/Swine/Fujian/F1/2010 (H1N2), we cloned its whole genome fragments using RT-PCR and performed phylogenetic analysis on the eight genes. As a result, the nucleotide sequences of HA, NA, PB1, PA, PB2, NP, M, and NS gene are similar to those of A/Swine/Shanghai/1/2007(H1N2) with identity of 98.9%, 98.9%, 99.0%, 98.6%, 99.0%, 98.9%, 99.3%, and 99.3%, respectively. Similar to A/Swine/Shanghai/1/2007(H1N2), we inferred that the HA, NP, M, and NS gene fragments of A/Swine/Fujian/F1/2010 (H1N2) strain were derived from classical swine influenza H3N2 subtype, NA and PB1 were derived from human swine influenza H3N2 subtype, and PB2 and PA genes were derived from avian influenza virus. This further validates the role of swine as a "mixer" for influenza viruses.

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