Intraovarian Gestation in Viviparous Teleosts: Unique Type of Gestation among Vertebrates

The intraovarian gestation, occurring in teleosts, makes this type of reproduction a such complex and unique condition among vertebrates. This type of gestation of teleosts is expressed in special morphological and physiological characteristic where occurs the viviparity and it is an essential component in the analysis of the evolutionary process of viviparity in vertebrates. In viviparous teleosts, during embryogenesis, there are not development of Müllerian ducts, which form the oviducts in the rest of vertebrates, as a result, exclusively in teleosts, there are not oviducts and the caudal region of the ovary, the gonoduct, connects the ovary to the exterior. The lack of oviducts defines that the embryos develop into the ovary, as intraovarian gestation. The ovary forms the oocytes which may develop different type of oogenesis, according with the storage of diverse amount of yolk, variation observed corresponding to the species. The viviparous gestation is characterized by the possible intimate contact between maternal and embryonic tissues, process that permits their metabolic interchanges. So, the nutrients obtained by the embryos could be deposited in the oocyte before fertilization, contained in the yolk (lecithotrophy), and may be completed during gestation by additional provisioning from maternal tissues to the embryo (matrotrophy). Then, essential requirements for viviparity in poeciliids and goodeids are characterized by: a) the diversification of oogenesis, with the deposition of different amount of yolk in the oocyte; b) the insemination, by the transfer of sperm to the female gonoduct and their transportation from the gonoduct to the germinal region of the ovary where the follicles develop; c) the intrafollicular fertilization; d) the intraovarian gestation with the development of embryos in intrafollicular gestation (as in poeciliids), or intraluminal gestation (as in goodeids); and, e) the origin of embryonic nutrition may be by lecithotrophy and matrotrophy. The focus of this revision compares the general and specific structural characteristics of the viviparity occurring into the intraovarian gestation in teleosts, defining this reproductive strategy, illustrated in this review with histological material in a poeciliid, of the species Poecilia latipinna (Lesueur, 1821) (Poeciliidae), and in a goodeid, of the species Xenotoca eiseni (Rutter, 1896) (Goodeidae).

The morphological and physiological studies Gorontalo local upland rice treated with drought and shade stresses

Crop growth and production are strongly affected by abiotic and biotic stresses. Survival rate frequently been used to evaluate rice drought tolerance with a low survival rate of rice plants undergoing drought stress leading to low yields. The aim of this research was to obtain Gorontalo local upland rice variants that are tolerant against drought and shade stresses by considering the morphological and physiological characteristics. The research was conducted in Bulotada Barat Village, Sipatana District, Gorontalo, from January to August 2017. Employing the randomized block design with three replications, the research consisted of two treatment factors. The first factor is the accession, which consists of two tolerant accessions; two moderately tolerant accessions, two drought-sensitive accessions, and two shade-sensitive accessions. The second factor pertains to the drought and shade stresses which consist of drought + 25% shade stress, drought + 50% shade stress, and a control. Irrigation in the drought control specimen was given until inundation reached 1.5 cm. In a drought-stressed situation, irrigation was given when the groundwater reached -30 to -35.9 kPa. The Ponda Merah accessions were the accessions that were tolerant against drought and shade stresses. The morphological characteristics of Gorontalo local upland rice that showed tolerance against drought and shade stresses were longer roots (33.20 cm), heavier dry weight (38.82 gr), a thinner leaf (186,56 cm2.g-1), and a higher yield (4,90 gr.cluster−1). The physiological characteristic of the Gorontalo local upland rice that showed tolerance against drought and shade stresses was the sugar content (0,73 g.g-1) which was higher than the other treatment.

Physiology, Taxonomy, and Sulfur Metabolism of the Sulfolobales, an Order of Thermoacidophilic Archaea

The order Sulfolobales (phylum Crenarchaeota) is a group of thermoacidophilic archaea. The first member of the Sulfolobales was discovered in 1972, and current 23 species are validly named under the International Code of Nomenclature of Prokaryotes. The majority of members of the Sulfolobales is obligately or facultatively chemolithoautotrophic. When they grow autotrophically, elemental sulfur or reduced inorganic sulfur compounds are their energy sources. Therefore, sulfur metabolism is the most important physiological characteristic of the Sulfolobales. The functions of some enzymes and proteins involved in sulfur reduction, sulfur oxidation, sulfide oxidation, thiosulfate oxidation, sulfite oxidation, tetrathionate hydrolysis, and sulfur trafficking have been determined. In this review, we describe current knowledge about the physiology, taxonomy, and sulfur metabolism of the Sulfolobales, and note future challenges in this field.

Inner ear biomechanics reveals Late Triassic origin of mammalian endothermy

Endothermy (“warm-bloodedness”) underpins the ecological dominance of mammals and birds in diverse environmental settings1-3. However, it is unclear when this crucial feature emerged during mammalian evolutionary history, as most fossil evidence is ambiguous4-25. Here, we show that new information on this key evolutionary transition can be obtained from the morphology of the endolymph-filled semicircular ducts of the inner ear that monitor head rotations and are essential for motor coordination, navigation, and spatial awareness26-31. Increased body temperature during the ectotherm–endotherm transition of mammal ancestors would decrease endolymph viscosity, negatively impacting the biomechanics of the semicircular ducts32,33, while simultaneously increasing activity levels34,35 required improved performance36. Specific morphological changes to the membranous ducts and enclosing bony canals were, therefore, necessary to maintain optimal functionality. We track these morphological changes in 341 vertebrates, including 56 extinct synapsids, and show that canals with relatively thin cross-sections and small radii of curvature are indicative of mammalian endothermy. This inner ear morphotype evolved abruptly ~233 million years ago, during the Late Triassic, in Mammaliamorpha. Our conclusion differs from previous suggestions3-17, and we interpret most stem-mammals as ectotherms. Endothermy as a crucial physiological characteristic joins other distinctive mammalian features that arose during this period of climatic instability37-39.

Constitutively Up-regulated Carbon Metabolism is an Adaptation to Low Temperature in the Antarctic Psychrophile Chlamydomonas sp. UWO241

The Antarctic alga Chlamydomonas sp. UWO241 is an obligate psychrophile that thrives in the cold but is unable to survive at moderate, seemingly innocuous temperatures. We dissect the responses of UWO241 to temperature stress using global metabolomic approaches. UWO241 exhibits slow growth at 4°C, a temperature closest to its natural habitat, and faster growth at higher temperatures of 10-15°C. We demonstrate that the slower growth-rate characteristic of UWO241 at 4⁰C is not necessarily a hallmark of stress. UWO241 constitutively accumulates high levels of protective metabolites including soluble sugars, polyamines and antioxidants at a range of steady-state temperatures. In contrast, the mesophile Chlamydomonas reinhardtii accumulates these metabolites only during cold stress. Despite low growth rates, 4°C-grown UWO241 cultures had a higher capacity to respond to heat stress (24°C) and accumulated increased amounts of antioxidants, lipids and soluble sugars, when compared to cultures grown at 10-15°C. We conclude that the slower growth rate and the unique psychrophilic physiological characteristic of UWO241 grown at 4⁰C result in a permanently re-routed steady-state metabolism, which contributes to its increased resistance to heat stress. Our work adds to the growing body of research on temperature stress in psychrophiles, many of which are threatened by climate change.

Single cell transcriptome analysis of decidua macrophages in normal and recurrent spontaneous abortion patients

ABSTRACTDue to the heterogeneity and different polarization state of decidual macrophages (dMΦ), they play an important role during the pregnancy, but their definition and exact function remain elusive. We isolated CD14+CD45+ dMΦ from the normal or RSA decidua by flow cytometry, followed by single cell RNA sequencing (scRNA-seq). In total, 23,062 single-cell transcriptomes of macrophage were profiled (12,470 Normal and 10,592 RSA), which were divided into 13 major clusters via T-distributed stochastic neighbor embedding (t-SNE) visualization. We observed that there is higher percentage composition of M1 cells (70.6%) in the normal decidua, and higher percentage composition of M2 cells (68.3%) in the RSA decidua. We identified new markers (M1: S100A8, S100A9, M2: SELENOP, FOLR2, RNASE1) and secreted cytokines (M1: IL1β, TNFSF13B and MMP9; M2: CCL3, CCL4) of the dMΦ. We found that cluster 10 as the specific cluster of dMΦ highly expressing BAG3 in normal group and cluster 7 specific highly expressing CXCL9/10/11 chemokine. After pseudo-time trajectory analysis, we found that the dMΦ formed a continuous “V-shaped” trajectory, with M1 and M2 type cells mainly occupying the two heads. We found that NFκB1, MYC and TCF12 acted as the key transcription factors of dMΦ. Our study redefined the polarization state and physiological characteristic of dMΦ in early normal and RSA pregnancy, which suggests a novel view and therapeutic target for spontaneous abortion prevention.

Changes of Physiological Characteristic Indexes in the Aging Process of the Liquid Spawn of Auricularia auricula

In order to explore the change rule of physiological indexes during the aging process of the liquid spawn of Auricularia auricula, this test chooses three species of Auricularia auricula(Hei29, Heiweibanjin and Heiweidanpian), which treasured the activities of antioxidant enzymes, antioxidant substances, membrane peroxidation degree and reactive oxygen concentration during different mycelia age. The conclusion showed that: at the same mycelial age, the vitality of Heiweidanpian was the strongest, Hei29 followed, and Heiweibanjin was the weakest; with the increase of mycelia age, Catalase (CAT) activity, Ascorbic Acid(ASA) content, Malondialdehyde (MDA) content and O2- production rate of the three kinds of Auricularia auricula increased continuously. Among them, ASA content, MDA content and O2- production rate increased significantly, while Superoxide Dismutase (SOD) activity decreased significantly; although the Proline (Pro) content and electrical conductivity of the three kinds of Auricularia auricula showed different trends, which decreased significantly at 14 to 16d and increased significantly at 8 to 10d, respectively, and H2O2 content increased significantly at 12 to 16d. It can be seen that SOD activity, CAT activity, ASA content, MDA content and O2- production rate have significant regular changes during the aging process of the liquid spawn of Auricularia auricula. The quantitative analysis found that when the MDA content is 1.42~1.72 μmol·g-1, the H2O2 content is 3.4~4.3 μmol·g-1 or the O2- production rate is 9.5~12.1 μmol·g-1·min-1, it can be considered Auricularia auricula just started to age or the aging degree is relatively low.

Effect of EGLN1 Genetic Polymorphisms on Hemoglobin Concentration in Andean Highlanders

The physiological characteristics of Andean natives living at high altitudes have been investigated extensively, with many studies reporting that Andean highlanders have a higher hemoglobin (Hb) concentration than other highlander populations. It has previously been reported that positive natural selection has acted independently on the egl-9 family hypoxia inducible factor 1 (EGLN1) gene in Tibetan and Andean highlanders and is related to Hb concentration in Tibetans. However, no study has yet revealed the genetic determinants of Hb concentration in Andeans even though several single-nucleotide polymorphisms (SNPs) in EGLN1 have previously been examined. Therefore, we explored the relationship between hematological measurements and tag SNPs designed to cover the whole EGLN1 genomic region in Andean highlanders living in Bolivia. Our findings indicated that haplotype frequencies estimated from the EGLN1 SNPs were significantly correlated with Hb concentration in the Bolivian highlanders. Moreover, we found that an Andean-dominant haplotype related to high Hb level may have expanded rapidly in ancestral Andean highlander populations. Analysis of genotype data in an ~436.3 kb genomic region containing EGLN1 using public databases indicated that the population structure based on EGLN1 genetic markers in Andean highlanders was largely different from that in other human populations. This finding may be related to an intrinsic or adaptive physiological characteristic of Andean highlanders. In conclusion, the high Hb concentrations in Andean highlanders can be partly characterized by EGLN1 genetic variants.