Distribution of freshwater fish in the south-western corner of Australia

This study investigates the distribution of freshwater fishes in the Busselton to Walpole Region. A total of 311 sites in 19 major catchments along the south-west coast from Capel to Walpole, were sampled using a variety of methods. New data was collated with that from previous studies to generate 15 species distribution maps. Habitat and life history notes and recommendations for conservation are made for each species. Changes in fish distribution are also commented upon. This study contributes to series of documents published for the purposes of water allocation planning in the Busselton to Walpole Region

Fate of the Blood Meal in Force-Fed, Diapausing Culex pipiens (Diptera: Culicidae)

Diapausing Culex pipiens L. do not display host-seeking behavior and can be induced to take blood only by being placed in contact with or in proximity to a host for prolonged periods. Such "force-fed” females do not use the blood for lipogenesis, and only some of them use the blood to initiate vitellogenesis. Diapausing Cx. pipiens that are induced to feed eject an average of 4.2-4.6 μl of blood during overnight feeding periods compared with an average of 0.1 μl for nondiapausing controls. The reduced avidity of diapausing females for blood, even under optimum conditions, and the ejection by fed females of blood volumes in excess of volumes usually retained indicate that such females are not physiologically programmed for taking and retaining blood. Data for uric acid and hematin excretion and bloodmeal volumes retained by diapausing females are positively correlated with diapause termination and yolk deposition. The occurrence of gonotrophic dissociation need not be invoked to explain the failure of some diapausing females to initiate vitellogenesis following a blood meal. Instead, this is explained by retention of small quantities of blood followed by incomplete digestion and is the expected result of a dose-dependent phenomenon determined by threshold blood volumes. Our data support the concept that the overwintering strategy of Cx. pipiens is limited to gonotrophic concordance in which overwintering females in nature do not take blood or develop eggs until diapause is terminate

Uterine miR-877-3p and let-7a-5p are increased during simulated menstruation in a mouse model

Heavy periods are common and debilitating, but we do not fully understand how they are caused. Increased understanding of menstrual bleeding could result in new treatments for problematic periods. Low oxygen levels are present in the womb lining during a period. These low oxygen levels help trigger the repair process required to stop menstrual bleeding. MicroRNAs (miRNAs) are small molecules that can affect cell function, and some are regulated by oxygen levels. We examined whether such miRNAs were present in the womb lining during a period. To overcome the variability present in humans, we studied the womb of mice given hormones to mimic the human menstrual cycle. We revealed that two miRNAs known to be regulated by oxygen levels were increased in the womb during menstruation. These miRNAs may help regulate menstrual blood loss and merit further study as a potential target for future treatments for heavy periods

The protein quality control system in motoneuron diseases

Spinal and bulbar muscular atrophy (SBMA) is a motoneuronal diseases caused by an elogated polyglutamine (polyQ) tract in the androgen receptor (AR). The polyQ expansion causes the AR protein to misfold and the binding with the ligand testosterone triggers a cascade of events, including ARpolyQ aggregation, that led to motoneuron death. The intracellular accumulation of misfolded ARpolyQ both altered the protein quality control system (PQC) and impaired the protective mechanisms deputed to refolding and clearance of misfolded proteins. In PQC, the molecular chaperones allow the refolding or the clearance of the misfolded proteins through the Ubiquitin Proteasome system (UPS) or the autophagic pathway. Moreover, emerging evidence reveal that ARpolyQ toxicity is not related only to motoneuron degeneration but also skeletal muscle damage plays a primary role in SBMA. AIM: The aim of the study was both to unravell the contribution of PQC in SBMA and to find molecular and pharmacological approaches for modulating PQC as potential therapeutic target. Methods: Western blot and filter retardation assay were used to analyse the biochemical properties of ARpolyQ and the protein level of PQC markers. RT-qPCR was used to quantify the mRNA expression of PQC genes in presence of ARpolyQ. Results: In SBMA motoneuronal cell line, we demonstrated that both UPS and autophagic pathway are impaired or blocked, leading to ARpolyQ accumulation into the aggregates. Moreover, analysis in SBMA animal model showed that in the spinal cord and in the skeletal muscle, the PQC could differ considerably in how degrading the mutant and misfolded ARpolyQ. In these conditions of PQC impairment we tested, in SBMA cell model, the overexpression of the small heat shock protein B8 (HspB8), involved in the autophagic pathway. HpB8 led to the autophagic removal of misfolded ARpolyQ, restorating the intracellular autophagic flux. Interestingly, we found that trehalose, a known autophagic stimulator, was able to induce the HspB8 expression and to facilitate the ARpolyQ clearance. Then, we tested the combined treatment of trehalose with Bicalutamide, an antiandrogen. Bicalutamide is able to slow down AR nuclear translocation and to retain it into the cytoplasm, where the autophagic pathway is active. Bicalutamide and trehalose showed synergic activity in the degradation of ARpolyQ. Conclusions: the PQC plays a crucial role in SBMA, the modulation of its activity with trehalose and Bicalutamide might be a promising approach for this no cure disease

Spacelab Science Results Study

Beginning with OSTA-1 in November 1981 and ending with Neurolab in March 1998, a total of 36 Shuttle missions carried various Spacelab components such as the Spacelab module, pallet, instrument pointing system, or mission peculiar experiment support structure. The experiments carried out during these flights included astrophysics, solar physics, plasma physics, atmospheric science, Earth observations, and a wide range of microgravity experiments in life sciences, biotechnology, materials science, and fluid physics which includes combustion and critical point phenomena. In all, some 764 experiments were conducted by investigators from the U.S., Europe, and Japan. The purpose of this Spacelab Science Results Study is to document the contributions made in each of the major research areas by giving a brief synopsis of the more significant experiments and an extensive list of the publications that were produced. We have also endeavored to show how these results impacted the existing body of knowledge, where they have spawned new fields, and if appropriate, where the knowledge they produced has been applied

Altered O-glycosylation of β1-adrenergic receptor N-terminal single-nucleotide variants modulates receptor processing and functional activity

Abstract N-terminal nonsynonymous single-nucleotide polymorphisms (SNPs) of G protein-coupled receptors (GPCRs) are common and often affect receptor post-translational modifications. Their functional implications are, however, largely unknown. We have previously shown that the human β1-adrenergic receptor (β1AR) is O-glycosylated in the N-terminal extracellular domain by polypeptide GalNAc transferase-2 that co-regulates receptor proteolytic cleavage. Here, we demonstrate that the common S49G and the rare A29T and R31Q SNPs alter these modifications, leading to distinct effects on receptor processing. This was achieved by in vitro O-glycosylation assays, analysis of native receptor N-terminal O-glycopeptides, and expression of receptor variants in cell lines and neonatal rat ventricular cardiomyocytes deficient in O-glycosylation. The SNPs eliminated (S49G) or introduced (A29T) regulatory O-glycosites that enhanced or inhibited cleavage at the adjacent sites (P52↓L53 and R31↓L32), respectively, or abolished the major site at R31↓L32 (R31Q). The inhibition of proteolysis of the T29 and Q31 variants correlated with increased full-length receptor levels at the cell surface. Furthermore, the S49 variant showed increased isoproterenol-mediated signaling in an enhanced bystander bioluminescence energy transfer β-arrestin2 recruitment assay in a coordinated manner with the common C-terminal R389G polymorphism. As Gly at position 49 is ancestral in placental mammals, the results suggest that its exchange to Ser has created a β1AR gain-of-function phenotype in humans. This study provides evidence for regulatory mechanisms by which GPCR SNPs outside canonical domains that govern ligand binding and activation can alter receptor processing and function. Further studies on other GPCR SNPs with clinical importance as drug targets are thus warranted.Abstract N-terminal nonsynonymous single-nucleotide polymorphisms (SNPs) of G protein-coupled receptors (GPCRs) are common and often affect receptor post-translational modifications. Their functional implications are, however, largely unknown. We have previously shown that the human β1-adrenergic receptor (β1AR) is O-glycosylated in the N-terminal extracellular domain by polypeptide GalNAc transferase-2 that co-regulates receptor proteolytic cleavage. Here, we demonstrate that the common S49G and the rare A29T and R31Q SNPs alter these modifications, leading to distinct effects on receptor processing. This was achieved by in vitro O-glycosylation assays, analysis of native receptor N-terminal O-glycopeptides, and expression of receptor variants in cell lines and neonatal rat ventricular cardiomyocytes deficient in O-glycosylation. The SNPs eliminated (S49G) or introduced (A29T) regulatory O-glycosites that enhanced or inhibited cleavage at the adjacent sites (P52↓L53 and R31↓L32), respectively, or abolished the major site at R31↓L32 (R31Q). The inhibition of proteolysis of the T29 and Q31 variants correlated with increased full-length receptor levels at the cell surface. Furthermore, the S49 variant showed increased isoproterenol-mediated signaling in an enhanced bystander bioluminescence energy transfer β-arrestin2 recruitment assay in a coordinated manner with the common C-terminal R389G polymorphism. As Gly at position 49 is ancestral in placental mammals, the results suggest that its exchange to Ser has created a β1AR gain-of-function phenotype in humans. This study provides evidence for regulatory mechanisms by which GPCR SNPs outside canonical domains that govern ligand binding and activation can alter receptor processing and function. Further studies on other GPCR SNPs with clinical importance as drug targets are thus warranted

Queens, pseudoqueens and laying workers reproductive competition in the Cape Honeybee (Apis mellifera capensis Eschscholtz)

In honeybees (Apis mellifera L.) the queen monopolises reproduction. However, especially after queen loss, workers can lay eggs, but are unable to mate. They produce haploid male offspring (drones) from unfertilised eggs via arrhenotokous parthenogenesis. In contrast, workers of the honeybee subspecies Apis mellifera capensis Eschscholtz typically produce diploid female offspring from unfertilised eggs thelytokously. After queen loss and without queen-derived brood A. m. capensis colonies can successfully requeen from worker-derived brood. This, however, is a relatively rare event in wild populations. Moreover, workerderived queens were described to be smaller, more worker-like and reproductively inferior. On the other hand, the fixation of the thelytokous trait relies mainly on sufficient numbers of viable drones produced by worker-derived queens. Small numbers of reproductively inferior worker-derived queens in A. m. capensis populations would be clearly counterintuitive. It is therefore necessary to quantify the significance of worker-dependant queen rearing pathways on the individual (queen) and on population level.Reproductive inferiority of worker-derived queens could not be confirmed on the individual (queen) level when comparing parameters indicating potential reproductive success of queen- and worker-derived queens. Queen- and worker-derived queens clearly showed a congruent range of reproductive performance. In queen rearing preference tests, increased acceptance of worker-derived female larvae was exactly counterbalanced by increased mortality, resulting in an equal number of eclosing virgin queens from an equal number of grafts in both test groups. Larval survival and successful eclosion is a prerequisite for a queen’s reproductive success. I found no difference in eclosion success for queen- and worker-derived virgin queens, indicating a similar potential for reproductive success in both queen types. Assessments of the developmental patterns of colonies headed by both queen and worker-derived queens in long-term experiments revealed no significant differences in reproductive success. Colonies headed by queen-derived queens and colonies headed by worker-derived queens could not be separated when comparing the different developmental pathways observed or from differences in worker-force. Reproductive dominance in A. m. capensis appeared tobe determined by a function of relative compositional and absolute quantitative pheromonal patterns, where individuals, which produce compositionally most queen-like blends in highest quantities, occupy top positions. Queen- and worker-derived virgin queens occupied intermediate positions between pseudoqueens and mated queens. However, no significant differences between the pheromonal status of queen- and worker-derived virgin queens were observed, suggesting a similar range of reproductive dominance for both queen types. In behavioural bioassays queen- and worker-derived virgin queens appeared to be similarly attractive to clustering workers and to drones in a drone congregation area, indicating no differences in potential reproductive success for queens from both origins for those parameters. The significant influence of the queen substance 9-ODA on attractiveness to workers and drones was confirmed. Rare requeening events from worker-derived female brood in queenless A.m. capensis do not satisfactorily explain the fixation of the thelytokous trait at a population level. I observed A. m. capensis worker ovipositing into empty artificial queen cell cups in queen-right colonies. The queen was confined behind a queen excluder grid in a separate compartment of the colony, to imitate reduced pheromonal flow, similar to swarming or superseding colonies. Eggs oviposited by workers in artificial queen cell cups were readily accepted for queen rearing and successful eclosion of viable virgin queens was observed. Consequently I suggested an alternative worker-dependant reproductive pathway in A. m. capensis, which was never described before: In swarming or superseding queenright colonies, laying workers may directly compete with the queen for reproductive success by ovipositing (instead of the queen) into natural queen cell cups. At a population level this reproductive tactic may result in large numbers of worker-derived queens of high reproductive quality in natural populations of A. m. capensis