Transmembrane conductance of small uncharged solutes such as glycerol typically occurs through aquaglyceroporins (Glps), which are commonly encoded by multiple genes in metazoan organisms. To date, however, little is known concerning the evolution of Glps in Crustacea or what forces might underly such apparent gene redundancy. Here, we show that Glp evolution in Crustacea is highly divergent, ranging from single copy genes in species of pedunculate barnacles, tadpole shrimps, isopods, amphipods and decapods to up to 10 copies in diplostracan water fleas although with monophyletic origins in each lineage. By contrast the evolution of Glps in Copepoda appears to be polyphyletic, with surprisingly high rates of gene duplication occurring in a genera- and species-specific manner. Based upon functional experiments on the Glps from a parasitic copepod ( Lepeophtheirus salmonis ), we show that such lineage-level gene duplication and splice variation is coupled with a high rate of neofunctionalization. In the case of L. salmonis , splice variation of a given gene resulted in tissue- or sex-specific expression of the channels, with each variant evolving unique sites for protein kinase C (PKC)- or protein kinase A (PKA)-regulation of intracellular membrane trafficking. The combined data sets thus reveal that mutations favouring a high fidelity control of intracellular trafficking regulation can be a selection force for the evolution and retention of multiple Glps in copepods.

Transmembrane glycerol transport is typically facilitated by aquaglyceroporins in Prokaryota and Eukaryota. In holometabolan insects however, aquaglyceroporins are absent, yet several species possess polyol permeable aquaporins. It thus remains unknown how glycerol transport evolved in the Holometabola. By combining phylogenetic and functional studies, here we show that a more efficient form of glycerol transporter related to the water-selective channel AQP4 specifically evolved and multiplied in the insect lineage, resulting in the replacement of the ancestral branch of aquaglyceroporins in holometabolan insects. To recapitulate this evolutionary process, we generate specific mutants in distantly related insect aquaporins and human AQP4 and show that a single mutation in the selectivity filter converted a water-selective channel into a glycerol transporter at the root of the crown clade of hexapod insects. Integration of phanerozoic climate models suggests that these events were associated with the emergence of complete metamorphosis and the unparalleled radiation of insects.

Water homeostasis and the structural integrity of the vertebrate lens is partially mediated by AQP0 channels. Emerging evidence indicates that external pH may be involved in channel gating. Here we show that a tetraploid teleost, the Atlantic salmon, retains 4 aqp0 genes (aqp0a1, -0a2, -0b1, and -0b2), which are highly, but not exclusively, expressed in the lens. Functional characterization reveals that, although each paralog permeates water efficiently, the permeability is respectively shifted to the neutral, alkaline, or acidic pH in Aqp0a1, -0a2, and -0b1, whereas that of Aqp0b2 is not regulated by external pH. Mutagenesis studies demonstrate that Ser(38), His(39), and His(40) residues in the extracellular transmembrane domain of -helix 2 facing the water pore are critical for the pH modulation of water transport. To validate these findings, we show that both zebrafish Aqp0a and -0b are functional water channels with respective pH sensitivities toward alkaline or acid pH ranges and that an N-terminal allelic variant (Ser(19)) of Aqp0b exists that abolishes water transport in Xenopus laevis oocytes. The data suggest that the alkaline pH sensitivity is a conserved trait in teleost Aqp0 a-type channels, whereas mammalian AQP0 and some teleost Aqp0 b-type channels display an acidic pH permeation preference.

In order to identify the optimal harvest time and monitor changes in raspberry (Rubus idaeus L cv. Glen Ample) fruit quality during ripening and storage, quality was assessed and compared by physical, chemical and sensory fruit quality criteria. Visual classification of fruit colour according to the Natural Colour System (NCS) chart and by physical measurement of fruit adherence to the receptacle or fruit compression resistance yielded parallel and highly significant results. The light red colour stage corresponding to NCS S code 3060-Y90R was identified as the optimal harvest stage for commercial fresh marketing of the 'Glen Ample' cultivar. Fruit harvested at this stage developed the same chemical and sensory qualities as in situ matured fruits and maintained high sensory quality after 8 days of storage in the dark at 2-3 degrees C. As the fruits mature, the concentration of titratable acids decreases, whereas the concentrations of anthocyanins and the sugar:acid ratio increase in parallel with colour development. While correlation analysis revealed a correlation between sensory traits like sweetness and acidity with sucrose and the sugar:acid ratio, respectively, the overall fruit tastefulness was not strongly correlated with any specific phytochemical component, thus illustrating the complex nature of this sensory trait. Due to its ease of performance, picking raspberry fruits related to a standardised colour chart is recommended for picking raspberry fruits with optimal quality. (C) 2015 Elsevier B.V. All rights reserved.

An emerging field in biomedical research is focusing on the roles of aquaporin water channels in parasites that cause debilitating or lethal diseases to their vertebrate hosts. The primary vectorial agents are hematophagous arthropods, including mosquitoes, flies, ticks and lice, however very little is known concerning the functional diversity of aquaporins in non-insect members of the Arthropoda. Here we conducted phylogenomic and functional analyses of aquaporins in the salmon louse, a marine ectoparasitic copepod that feeds on the skin and body fluids of salmonids, and used the primary structures of the isolated channels to uncover the genomic repertoires in Arthropoda.

Summary Experiments were conducted on-Station and in growers’ nurseries with the aim of developing cheap techniques for the production of pot-grown raspberry long canes with high yield potential. In an earlier paper, we reported the feasibility of producing raspberry long canes with a yield potential of > 3 kg fruit per cane.The experiments presented here confirm that such high yields can be achieved on a regular basis, even when applying intensified and cheaper production techniques.Thus, the pot size could be reduced from the previous 3.5 l, to 2.5 l and the plant spacing could be decreased from 200 cm20 cm, to 100 cm×20 cm without loss of cane yield potential. Even at a plant spacing of 55 cm×20 cm, canes with a yield potential close to 3 kg per cane were produced. It was also shown that, during the cropping year, an additional one or two new canes with the same high yield potential could be raised concurrently with flowering and fruiting of the old cane, without a significant loss of yield on the old fruiting cane.When two canes were produced and cropped in each pot, either as two separate canes or as forked single shoots with two canes, yields of almost 4 kg per pot were achieved. However, as in our earlier experiments, long canes with such high yield potentials could only be produced under greenhouse conditions in the cool Norwegian environment.These experiments confirm the feasibility of producing raspberry long canes with yield potentials of ≥ 3 kg fruit per cane on a regular basis, even with intensified and cheaper production techniques.

Two main categories of flowering and fruiting habits exist in strawberry: 1) seasonal flowering (SF) genotypes which produce only one flush of flowering and fruiting in the Spring; and 2) recurrent flowering or everbearing (EB) genotypes which, in addition to a spring flush, produce more or less continuous flowering and fruiting throughout the growing season. Both types are represented in the octoploid cultivated strawberry, Fragaria x ananassa Duch., as well as in the diploid wood strawberry, F. vesca L. Independent of ploidy level, SF genotypes have proved to be basically short-day (SD) plants, while EB genotypes are basically long-day (LD) plants. However, flower induction is controlled in both groups, by a pronounced interaction of photoperiod and temperature, which has complicated resolution of the underlying response mechanisms. At low temperatures (< 10 degrees C), both SF and EB genotypes are essentially day-neutral, while, at higher temperatures, they exhibit contrasting photoperiodic responses. Significant progress has been made in elucidating the genetic factors and molecular mechanisms underlying the complex flowering responses of strawberry, using the diploid E vesca as a model plant. Many of the central genetic components of the flowering pathways which are known in Arabidopsis thaliana have also been identified in strawberry. A major breakthrough was identification of the SFL (SEASONAL FLOWERING LOCUS) gene in F. vesca as a homologue of the Arabidopsis TERMINAL FLOWER1 (FvTFL1) gene, and the recent demonstration of its function as a genetic switch controlling the opposite photoperiodic responses of the SF and EB genotypes of strawberry.

Two female and two male cultivars of cloudberry (Rubus chamaemorus L.) have previously been released as a result of clone evaluation at the Norwegian Institute for Agricultural and Environmental Research. Selection criteria have been number of pistils or stamens per flower, number of flowers and number of shoots per m2. Recently two groups of clones have been evaluated with the aim of finding new cultivars for release. The clones were collected at different locations in Norway, as well as in England and at Svalbard. Results from harvesting in 2005 to 2008 show large genetic variation in all evaluated traits and indicate good production potential for some of the tested clones. Previously released ‘Fjellgull’ and ‘Fjordgull’ are confirmed as stable and high producing. Of the clones evaluated for the first time, especially clone 102 and clone 306 are possible contenders for release. In addition to prior selection criteria based on berry yield, berry contents also have been analysed. The results indicate that clones with a northern origin have higher levels of total phenols, total anthocyanins and carotenoids than clones of a southern origin.

Jornada Anual de la Seccio d’Aquicultura de la Societat Catalana de Biologia, Avencos en Recerca en Aquicultura, 12 de Juny de 2015, Barcelona.-- 1 page