Impact of telomere length and mitochondrial DNA copy number variants on survival of newborn cloned calves

An established technology to create cloned animals is through the use of somatic cell nuclear transfer (SCNT), in which reprogramming the somatic cell nucleus to a totipotent state by enucleated oocyte cytoplasm is a necessary process, including telomere length reprogramming. The limitation of this technology; however, is that the live birth rate of offspring produced through SCNT is significantly lower than that of IVF. Whether and how telomere length play a role in the development of cloned animals is not well understood. Only a few studies have evaluated this association in cloned mice, and fewer still in cloned cows. In this study, we investigated the difference in telomere length as well as the abundance of some selected molecules between newborn deceased cloned calves and normal cows of different ages either produced by SCNT or via natural conception, in order to evaluate the association between telomere length and abnormal development of cloned cows. The absolute telomere length and relative mitochondrial DNA (mtDNA) copy number were determined by real-time quantitative PCR (qPCR), telomere related gene abundance by reverse-transcription quantitative PCR (RT-qPCR), and senescence-associated β-galactosidase (SA-β-gal) expression by SA-β-gal staining. The results demonstrate that the newborn deceased SCNT calves had significantly shortened telomere lengths compared to newborn naturally conceived calves and newborn normal SCNT calves. Significantly lower mtDNA copy number, and significantly lower relative abundance of LMNB1 and TERT, higher relative abundance of CDKN1A, and aberrant SA-β-gal expression were observed in the newborn deceased SCNT calves, consistent with the change in telomere length. These results demonstrate that abnormal telomere shortening, lower mtDNA copy number and abnormal abundance of related genes were specific to newborn deceased SCNT calves, suggesting that abnormally short telomere length may be associated with abnormal development in the cloned calves.

A case of gynandromorphism in Hyalomma anatolicum (Ixodida: Ixodidae)

We present a field-collected Hyalomma anatolicum gynandromorph in Xinjiang, China. Compared to the normal H. anatolicum, the gynandromorphic tick was a typical bipartite protogynander: half of the tick body displayed normal female traits, whereas the other side showed normal male traits. The engorged gynandromorphic tick laid hundreds of eggs, and the eggs looked normal.

Enantioselective effect of trifloxystrobin in early-stage zebrafish (Danio rerio) embryos: Cardiac abnormalities impacted by E,E-trifloxystrobin enantiomer

Trifloxystrobin (TFS) is one of the extensively used strobilurin fungicides, which is composed of four enantiomers and its active form is E,E-TFS. In this study, we assess the acute toxicity of four enantiomers, E,E-, E,Z-, Z,E-, and Z,Z-TFS in zebrafish (Danio rerio) embryos. Among the four enantiomers, only E,E-TFS was found to be acutely toxic, with an estimated LC₅₀ value of 0.68 mg/L. Treatment with E,E-TFS resulted in various phenotypic changes in the embryos, including pericardial and yolk-sac edema, spine curvature, and blood pooling. And it shortened the whole body length in the treated embryos by increasing the total intersegmental vessel numbers using a Tg(fli1a:EGFP) zebrafish line. Further study using Tg(cmlc2:EGFP) zebrafish line revealed that E,E-TFS treatment was associated with cardiac malformations, a failure of heart function, and a lowered heartbeat rate at the concentration of 0.25 mg/L. Also, the differential gene expression analysis identified significant down-regulation of vmhc and cacna1c genes encoding ventricular myosin heavy chain and calcium voltage-gated channel subunit alpha 1C, which are crucial for heart development. These results suggest the need for regular monitoring of E,E-TFS enantiomers after field application and further research into their potential chronic effects on environmental organisms.

Ingestion of contaminated kelps by the herbivore Tetrapygus niger: Negative effects on food intake, growth, fertility, and early development

Macrocystis pyrifera reaches distant areas after detachment, accumulate heavy metals, and serve as trophic subsidy. In this context, effects on both adults and larvae of Tetrapygus niger fed with polluted kelps were determined by assessing growth, fertility, and early larval development. Results revealed that sea urchins fed with polluted kelps from highly impacted zone (HIZ) showed a lower growth (3.6% gained weight) and gamete release (358 cells mL^-1) than those fed with non-impacted kelps (NIZ) (19.3% and 945 cells mL^-1). The HIZ treatment showed a developmental delay in comparison to NIZ, accounted mainly by the abundance of malformed 2-arm pluteus larvae (10-15%) during most of the culture. Malformed 4-arm pluteus larvae showed a constant increase, reaching 37% at the end of the culture. Thus, the pollutants ingested by sea urchins can be transferred to their offspring and cause negative effects in their early development, categorizing M. pyrifera as a pollutant carrier.

High resistance of Acropora coral gametes facing copper exposure

Pollution by heavy metals remains today an important threat to the health of humans and ecosystems, but there is still a paucity of data on the response of early life stages of key organisms. In this context, the present work assessed the fertilization success rate of two Acropora species (A. cytherea and A. pulchra) from the French Polynesia reefs exposed to six increasing copper concentrations in seawater. The two species showed a relatively high tolerance to copper (4h30-EC50 was 69.4 ± 4.8 μg L(-1) and 75.4 ± 6.4 μg L(-1) for A. cytherea and A. pulchra, respectively). As Cu concentration increases, an increasing proportion of deformed embryos was recorded (67.6% and 58.5% for A. cytherea and A. pulchra, respectively, at 220 μg Cu L(-1)). These results demonstrated thus, that high levels of copper could negatively impair the normal fertilization process of coral gametes and therefore alter the renewal of coral populations. Since the two Acropora species investigated in this study displayed a high resistance to copper, these results should be considered in the context of multiple stressors associated with climate change, where rising temperature or ocean acidification may significantly exacerbate copper toxicity.

[A neonate with aprosopia, monomelia and celosomy]

The specimen of which it is a matter here takes part of the heritage of the Museum of Anatomy and Embryology of the Faculty of Medicine of the Université Libre de Bruxelles. Its medical history is completely unknown, because it takes part of an ancient collection of pathological anatomy saved from destruction and recovered by the laboratory of Anatomy and Embryology. The specimen is strongly folded up on itself ("in extension"), its length so arranged is about 25 cm; unfolded, it develops to 45 cm. Cranial perimeter is of 31 cm. Unfortunately, the brain was removed during the initial analysis, and only the examination of the braincase allows to draw some conclusions on the probable state of the encephalon. The face is rudimentary, without any orbit, and the oral cavity is limited to a vertical slit, revealing small strongly tipped up maxillary bones. A double proboscis is present. The trunk is characterised by a rather broad celosomy, with exhibition of the intestines, the liver and the pancreas. Anal atresia is observed, and the external sexual organs are hypoplastic and ambiguous. The whole left lower limb is absent, including the left half of the pelvis, corresponding to a left unilateral complete ectromelia. The neck is in hyperextension, so that the occipital region seems extremely welded in the cervical spine. However, CT examination does not confirm the presence of such fusion, but on the other hand, reveals a severe axial diversion of the spine with hyperextension. Extremely rare in humans, the aprosopia is more readily present in some animals (sheep). Its association with a monomelia and a celosomy seems not yet described.

The fate of the embedded virgin sand flea Tunga penetrans: hypothesis, self-experimentation and photographic sequence

We describe the morphological development of a single penetrated female sand flea (Tunga penetrans) in a medical expatriate working in Madagascar. The embedded parasite developed abnormally in two aspects. First, it lived twice as long as usually. Second, it did not expel a single egg during a period of two months. We explain these abnormalities by the fact that the female sand flea remained virgin after the penetration into the skin and, therefore, mature eggs did not develop. Our observations are seminal findings in a long dispute between entomologists and suggest that normally the fertilization of a female sand flea takes place on-host when it is already embedded in the epidermis. We conclude that a single sand flea lesion in a traveller may develop in a different way as compared to parasites penetrating into the skin of inhabitants living in endemic areas.

Comparative proteomic analysis of off-type and normal phenotype somatic plantlets derived from somatic embryos of Feijoa (Acca sellowiana (O. Berg) Burret)

Morphological disorders in a relevant portion of emerged somatic embryos have been a limiting factor in the true-to-type plantlet formation in Acca sellowiana. In this sense, the present study undertook a comparison between normal phenotype and off-type somatic plantlets protein profiles by means of the 2-D DIGE proteomics approach. Off-type and normal phenotype somatic plantlets obtained at 10 and 20 days conversion were evaluated. Results indicated 12 exclusive spots between normal and off-type plantlets at 10 days conversion, and 17 exclusive spots at 20 days conversion. Also at 20 days conversion, 4 spots were differentially expressed, up- or down-regulated. Two proteins related to carbohydrate metabolism were only expressed in off-types at 10 days conversion, suggesting a more active respiratory pathway. A vicilin-like storage protein was only found in off-types at 20 days conversion, indicating that plantlets may present an abnormality in the mobilization of storage compounds, causing reduced vigor in the development of derived plantlets. The presence of heat shock proteins were only observed during formation of normal phenotype somatic plantlets, indicating that these proteins may be involved in normal morphogenesis of plantlets formed. These new findings shed light on possible genetic or epigenetic mechanisms governing A. sellowiana morphogenesis.