Migration patterns and navigation cues of Atlantic salmon post-smolts migrating from 12 rivers through the coastal zones around the Irish Sea

The freshwater phase of the first seaward migration of juvenile Atlantic salmon (Salmo salar) is relatively well understood when compared with our understanding of the marine phase of their migration. In 2021, 1008 wild and 60 ranched Atlantic salmon smolts were tagged with acoustic transmitters in 12 rivers in England, Scotland, Northern Ireland and Ireland. Large marine receiver arrays were deployed in the Irish Sea at two locations: at the transition of the Irish Sea into the North Atlantic between Ireland and Scotland, and between southern Scotland and Northern Ireland, to examine the early phase of the marine migration of Atlantic salmon smolts. After leaving their natal rivers' post-smolt migration through the Irish Sea was rapid with minimum speeds ranging from 14.03 to 38.56 km.day⁻¹ for Atlantic salmon smolts that entered the Irish Sea directly from their natal river, to 9.69–39.94 km.day⁻¹ for Atlantic salmon smolts that entered the Irish Sea directly from their natal estuary. Population minimum migration success through the study area was strongly correlated with the distance of travel, populations further away from the point of entry to the open North Atlantic exhibited lower migration success. Post-smolts from different populations experienced different water temperatures on entering the North Atlantic. This was largely driven by the timing of their migration and may have significant consequences for feeding and ultimately survivorship. The influence of water currents on post-smolt movement was investigated using data from previously constructed numerical hydrodynamic models. Modeled water current data in the northern Irish Sea showed that post-smolts had a strong preference for migrating when the current direction was at around 283° (west-north-west) but did not migrate when exposed to strong currents in other directions. This is the most favorable direction for onward passage from the Irish Sea to the continental shelf edge current, a known accumulation point for migrating post-smolts. These results strongly indicate that post-smolts migrating through the coastal marine environment are: (1) not simply migrating by current following (2) engage in active directional swimming (3) have an intrinsic sense of their migration direction and (4) can use cues other than water current direction to orientate during this part of their migration.     

Enhanced production of poly(lactate-co-3-hydroxybutyrate) from xylose in engineered Escherichia coli overexpressing a galactitol transporter

Poly(lactate-co-3-hydroxybutyrate) (P(LA-co-3HB)) was previously produced from xylose in engineered Escherichia coli. The aim of this study was to increase the polymer productivity and LA fraction in P(LA-co-3HB) using two metabolic engineering approaches: (1) deletions of competing pathways to lactate production and (2) overexpression of a galactitol transporter (GatC), which contributes to the ATP-independent xylose uptake. Engineered E. coli mutants (ΔpflA, Δpta, ΔackA, ΔpoxB, Δdld, and a dual mutant; ΔpflA?+?Δdld) and their parent strain, BW25113, were grown on 20 g l^?1 xylose for P(LA-co-3HB) production. The single deletions of ΔpflA, Δpta, and Δdld increased the LA fraction (58–66 mol%) compared to BW25113 (56 mol%). In particular, the ΔpflA?+?Δdld strain produced P(LA-co-3HB) containing 73 mol% LA. Furthermore, GatC overexpression increased both polymer yields and LA fractions in ΔpflA, Δpta, and Δdld mutants, and BW25113. The ΔpflA?+?gatC strain achieved a productivity of 8.3 g l^?1, which was 72 % of the theoretical maximum yield. Thus, to eliminate limitation of the carbon source, higher concentration of xylose was fed. As a result, BW25113 harboring gatC grown on 40 g l^?1 xylose reached the highest P(LA-co-3HB) productivity of 14.4 g l^?1. On the other hand, the ΔpflA?+?Δdld strain grown on 30 g l^?1 xylose synthesized 6.4 g l^?1 P(LA-co-3HB) while maintaining the highest LA fraction (73 mol%). The results indicated the usefulness of GatC for enhanced production of P(LA-co-3HB) from xylose, and the gene deletions to upregulate the LA fraction in P(LA-co-3HB). The polymers obtained had weight-averaged molecular weights in the range of 34,000–114,000.     

In situ hybridization analysis of the temporospatial expression of the midkine/pleiotrophin family in rat embryonic pituitary gland

Pituitary gland development is controlled by numerous signaling molecules, which are produced in the oral ectoderm and diencephalon. A newly described family of heparin-binding growth factors, namely midkine (MK)/pleiotrophin (PTN), is involved in regulating the growth and differentiation of many tissues and organs. Using in situ hybridization with digoxigenin-labeled cRNA probes, we detected cells expressing MK and PTN in the developing rat pituitary gland. At embryonic day 12.5 (E12.5), MK expression was localized in Rathke’s pouch (derived from the oral ectoderm) and in the neurohypophyseal bud (derived from the diencephalon). From E12.5 to E19.5, MK mRNA was expressed in the developing neurohypophysis, and expression gradually decreased in the developing adenohypophysis. To characterize MK-expressing cells, we performed double-staining of MK mRNA and anterior pituitary hormones. At E19.5, no MK-expressing cells were stained with any hormone. In contrast, PTN was expressed only in the neurohypophysis primordium during all embryonic stages. In situ hybridization clearly showed that MK was expressed in primitive (immature/undifferentiated) adenohypophyseal cells and neurohypophyseal cells, whereas PTN was expressed only in neurohypophyseal cells. Thus, MK and PTN might play roles as signaling molecules during pituitary development.     

Evidence of ‘new glume wheat’ from the Late Neolithic (Copper Age) of south-eastern Hungary (4th millennium cal. b.c.)

In 2000, remains of an unknown Triticum species—later named ‘new glume wheat’ (NGW)—were identified in the archaeobotanical material of Neolithic and Bronze Age Greek sites. The presence of NGW was later reported from several other locations across Europe, from the seventh to the first millennium cal. b.c. During the systematic archaeobotanical survey of the multiperiod site of Hódmez?vásárhely–Kopáncs I., Olasz-tanya (5310–2936 cal. b.c.) more than 2,000 cereal remains were recovered. During the morphological analyses, ten spikelet forks showed the distinctive traits of NGW, therefore morphometric analyses were conducted on the remains to reinforce the morphological identification. The results suggest that both approaches—morphological and morphometric—should be applied in parallel to securely separate the NGW remains from Triticum turgidum L. ssp. dicoccum (Schrank) Thell. (emmer) and T. monococcum L. ssp. monococcum (einkorn). All NGW glume bases were recovered from Late Copper Age features (3338–3264 cal. b.c.) of the settlement, which represent the Baden culture of the Great Hungarian Plain. Similarly to other Baden culture sites of the Carpathian Basin einkorn and emmer dominated the crop production of the settlement. The ratio of the NGW remains within the cereal assemblage was measured to be 0.48 %, which suggests that NGW did not have the status of a regular crop; still it may have been part of the accompanying weed flora of the cereal fields during the fourth millennium in the south-eastern Great Hungarian Plain landscape.     

Cellular expression and localization of DGKζ-interacting NAP1-like proteins in the brain and functional implications under hypoxic stress

Diacylglycerol kinase (DGK) catalyzes conversion of a lipid second messenger diacylglycerol to another messenger molecule phosphatidic acid. Consequently, DGK plays a pivotal role in cellular pathophysiology by regulating the levels of these two messengers. We reported previously that DGKζ translocates from the nucleus to cytoplasm in hippocampal neurons under ischemic/hypoxic stress. In addition, we also identified nucleosome assembly protein 1 (NAP1)-like proteins NAP1L1 and NAP1L4 as novel DGKζ-interacting partners using a proteomic approach and revealed that these NAP1-like proteins induce cytoplasmic translocation of DGKζ in overexpressed cells because NAP1-like proteins associate with the nuclear localization signal of DGKζ and block its nuclear import via importin α. In the present study, we examined whether NAP1-like proteins are expressed in the brain and whether the molecular interaction of DGKζ and NAP1-like proteins would be changed in the brain after hypoxic stress. Immunohistochemistry revealed that NAP1L1 and NAP1L4 are widely expressed in neurons and glial cells in the brain with some differences. After 3 days of transient whole-body hypoxic stress, DGKζ translocated from the nucleus to cytoplasm in hippocampal pyramidal neurons, whereas NAP1-like proteins remained in the cytoplasm. Contrary to our expectations, NAP1-like proteins showed no change in their expression levels. The molecular interaction between DGKζ and NAP1-like proteins was attenuated after hypoxic stress. These results suggest that DGKζ cytoplasmic translocation in neurons under hypoxic stress is regulated by some mechanism which differs from that mediated by NAP1-like proteins.     

Rates of genomic divergence in humans,chimpanzees and their lice

The rate of DNA mutation and divergence is highly variable across the tree of life. However, the reasons underlying this variation are not well understood. Comparing the rates of genetic changes between hosts and parasite lineages that diverged at the same time is one way to begin to understand differences in genetic mutation and substitution rates. Such studies have indicated that the rate of genetic divergence in parasites is often faster than that of their hosts when comparing single genes. However, the variation in this relative rate of molecular evolution across different genes in the genome is unknown. We compared the rate of DNA sequence divergence between humans, chimpanzees and their ectoparasitic lice for 1534 protein-coding genes across their genomes. The rate of DNA substitution in these orthologous genes was on average 14 times faster for lice than for humans and chimpanzees. In addition, these rates were positively correlated across genes. Because this correlation only occurred for substitutions that changed the amino acid, this pattern is probably produced by similar functional constraints across the same genes in humans, chimpanzees and their ectoparasites.