Migrants in the Mediterranean: Do's and Don’ts in Maritime Interdiction

Mediterranean European Union member states have to deal with thousands of migrants arriving by sea every year. Frontex (the EU external borders agency) organizes joint surveillance operations at sea to interdict these migrant boats, helping states to cope with the problem. This article discusses the legality of these maritime interdictions done by Frontex according to the international law of the sea as well as the conformity of the operations with the nonrefoulement principle.     

Chromosome 22q11.2 deletion syndrome: prenatal diagnosis,array comparative genomic hybridization characterization using uncultured amniocytes and literature review

We present prenatal diagnosis of de novo 22q11.2 microdeletion syndrome using uncultured amniocytes in a pregnancy with conotruncal heart malformations in the fetus. We discuss the genotype–phenotype correlation and the consequence of haploinsufficiency of TBX1, COMT, UFD1L, GNB1L and MED15 in the deleted region. We review the literature of chromosomal loci and genes responsible for conotruncal heart malformations and tetralogy of Fallot.     

Rope trauma,sedation, disentanglement,and monitoring‐tag associated lesions in a terminally entangled North Atlantic right whale (Eubalaena glacialis)

A chronically entangled North Atlantic right whale, with consequent emaciation was sedated, disentangled to the extent possible, administered antibiotics, and satellite tag tracked for six subsequent days. It was found dead 11 d after the tag ceased transmission. Chronic constrictive deep rope lacerations and emaciation were found to be the proximate cause of death, which may have ultimately involved shark predation. A broadhead cutter and a spring‐loaded knife used for disentanglement were found to induce moderate wounds to the skin and blubber. The telemetry tag, with two barbed shafts partially penetrating the blubber was shed, leaving barbs embedded with localized histological reaction. One of four darts administered shed the barrel, but the needle was found postmortem in the whale with an 80º bend at the blubber‐muscle interface. This bend occurred due to epaxial muscle movement relative to the overlying blubber, with resultant necrosis and cavitation of underlying muscle. This suggests that rigid, implanted devices that span the cetacean blubber muscle interface, where the muscle moves relative to the blubber, could have secondary health impacts. Thus we encourage efforts to develop new tag telemetry systems that do not penetrate the subdermal sheath, but still remain attached for many months.     

Right‐ and left‐handed three‐helix proteins. I. Experimental and simulation analysis of differences in folding and structure

Despite the large number of publications on three‐helix protein folding, there is no study devoted to the influence of handedness on the rate of three‐helix protein folding. From the experimental studies, we make a conclusion that the left‐handed three‐helix proteins fold faster than the right‐handed ones. What may explain this difference? An important question arising in this paper is whether the modeling of protein folding can catch the difference between the protein folding rates of proteins with similar structures but with different folding mechanisms. To answer this question, the folding of eight three‐helix proteins (four right‐handed and four left‐handed), which are similar in size, was modeled using the Monte Carlo and dynamic programming methods. The studies allowed us to determine the orders of folding of the secondary‐structure elements in these domains and amino acid residues which are important for the folding. The obtained data are in good correlation with each other and with the experimental data. Structural analysis of these proteins demonstrated that the left‐handed domains have a lesser number of contacts per residue and a smaller radius of cross section than the right‐handed domains. This may be one of the explanations of the observed fact. The same tendency is observed for the large dataset consisting of 332 three‐helix proteins (238 right‐ and 94 left‐handed). From our analysis, we found that the left‐handed three‐helix proteins have some less‐dense packing that should result in faster folding for some proteins as compared to the case of right‐handed proteins.Proteins 2013; © 2013 Wiley Periodicals, Inc.     

Subnuclear development of the zebrafish habenular nuclei requires ER translocon function

The dorsal habenular nuclei (Dh) of the zebrafish are characterized by significant left–right differences in gene expression, anatomy, and connectivity. Notably, the lateral subnucleus of the Dh (LsDh) is larger on the left side of the brain than on the right, while the medial subnucleus (MsDh) is larger on the right compared to the left. A screen for mutations that affect habenular laterality led to the identification of the sec61a-like 1(sec61al1) gene. In sec61al1^c163 mutants, more neurons in the LsDh and fewer in the MsDh develop on both sides of the brain. Generation of neurons in the LsDh occurs more rapidly and continues for a longer time period in mutants than in WT. Expression of Nodal pathway genes on the left side of the embryos is unaffected in mutants, as is the left sided placement of the parapineal organ, which promotes neurogenesis in the LsDh of WT embryos. Ultrastructural analysis of the epithalamus indicates that ventricular precursor cells, which form an epithelium in WT embryos, lose apical-basal polarity in sec61al1^c163 mutants. Our results show that in the absence of sec61al1, an excess of precursor cells for the LsDh exit the ventricular region and differentiate, resulting in formation of bilaterally symmetric habenular nuclei.     

Essential roles of fibronectin in the development of the left-right embryonic body plan

Studies in Xenopus laevis suggested that cell-extracellular matrix (ECM) interactions regulate the development of the left–right axis of asymmetry; however, the identities of ECM components and their receptors important for this process have remained unknown. We discovered that FN is required for the establishment of the asymmetric gene expression pattern in early mouse embryos by regulating morphogenesis of the node, while cellular fates of the nodal cells, canonical Wnt and Shh signaling within the node were not perturbed by the absence of FN. FN is also required for the expression of Lefty 1/2 and activation of SMADs 2 and 3 at the floor plate, while cell fate specification of the notochord and the floor plate, as well as signaling within and between these two embryonic organizing centers remained intact in FN-null mutants. Furthermore, our experiments indicate that a major cell surface receptor for FN, integrin α5β1, is also required for the development of the left–right asymmetry, and that this requirement is evolutionarily conserved in fish and mice. Taken together, our studies demonstrate the requisite role for a structural ECM protein and its integrin receptor in the development of the left–right axis of asymmetry in vertebrates.     

Phenological changes in North Atlantic right whale habitat use in Massachusetts Bay

The North Atlantic right whale (Eubalaena glacialis) is one of the world's most highly endangered baleen whales, with approximately 400–450 individuals remaining. Massachusetts Bay (MB) and Cape Cod Bay (CCB) together comprise one of seven areas in the Gulf of Maine where right whales seasonally congregate. Here, we report on acoustically detected presence of right whales in MB over a nearly 6 year period, July 2007–April 2013, a time of both rapid ocean warming throughout the Gulf of Maine and apparent changes in right whale migratory dynamics. We applied an automated detection algorithm to assess hourly presence of right whale “up‐calls” in recordings from a 19‐channel acoustic array covering approximately 4,000 km² in MB. Over the survey, up‐calls were detected in 95% of 8 day periods. In each year, as expected, we observed a “peak season” of elevated up‐call detections in late winter and early spring corresponding to the season when right whales congregate to feed in CCB. However, we also saw an increase in right whale occurrence during time periods thought to be part of the “off‐season.” With the exception of 2009–2010, when acoustic presence was unusually low, the mean percent of hours in which up‐calls were detected increased every year, both during the peak season (from 38% in 2008 to 70% in 2012), and during the summer–fall season (from 2% in 2007 to 13% in 2012). Over the entire study, the peak season start date varied between 17 January and 26 February. Changes in right whale phenology in MB likely reflect broadscale changes in habitat use in other areas within the species range. This study demonstrates the value of continuous long‐term survey datasets to detect and quantify shifts in cetacean habitat use as environmental conditions change and the long‐term continued survival of right whales remains uncertain.     

Isolation and functional characterization of the FLOWERING LOCUS T homolog, the LsFT gene, in lettuce

High temperature-induced bolting of lettuce is undesirable agriculturally, making it important to find the mechanism governing the transition from vegetative to reproductive growth. FLOWERING LOCUS T (FT) genes play important roles in the induction of flowering in several plant species. To clarify floral induction in lettuce, we isolated the FT gene (LsFT) from lettuce. Sequence analysis and phylogenetic relationships of LsFT revealed considerable homology to FT genes of Arabidopsis, tomato, and other species. LsFT induced early flowering in transgenic Arabidopsis, but was not completely effective compared to AtFT. LsFT mRNA was abundant in the largest leaves under flowering-inducible conditions (higher temperatures). Gene expression was correlated with flower differentiation of the shoot apical meristem. Our results suggest that LsFT is a putative FT homolog in lettuce that regulates flower transition, similar to its homolog in Arabidopsis. This is the first information on the lettuce floral gene for elucidating regulation of the flowering transition in lettuce.     

Vertebral and rib anatomy in Caperea marginata: Implications for evolutionary patterning of the mammalian vertebral column

The pygmy right whale, Caperea marginata, is a rare mysticete cetacean with an unusual suite of axial skeletal characters. Distally expanded first ribs, a long thorax with broadly overlapping vertebral transverse processes, plate‐like posterior ribs, and a short tail contrast with other cetaceans and suggest unique developmental patterning. Twenty‐four individuals of diverse ontogenetic age were available for analysis. Multiple, variable examples of incomplete rib fusion in dependent calves indicate that the first rib of adults is an ontogenetic fusion product of ribs 1 and 2. The composite rib articulates by way of its anterior (Rib1) component to the sternum and by way of its posterior (Rib2) component with thoracic vertebra 2. Thoracic vertebra 1 lacks rib articulations. When rib fusion is taken into account, the most frequent column formulas are C7T18L1Cd16–17 = 42–43 and C7T17L1Cd16–18 = 41–43. Thoracic and lumbar series are not reciprocal in count, arguing against their developmental linkage. Instead, parallel reduction in both lumbar and caudal counts supports the existence of neocete patterning in Caperea, as in all other living cetaceans. Ontogenetic vertebral column elongation is most marked in the posterior thorax, lumbos, and anterior tail. Vertebrae in these column regions are excellent predictors of total body length.     

Coastal,offshore, and migratory movements of South African right whales revealed by satellite telemetry

In September 2001, 21 satellite‐monitored radio tags were deployed on southern right whales in South African waters, 15 of which transmitted for 25–161 d. Most coastwise movement on the south coast occurred in a westerly direction with cow‐calf pairs moving slowest. Three whales tagged on the west coast and one tagged on the south coast moved north into St Helena Bay, a probable feeding ground, where residence times were 36–100 d. Five animals tracked after leaving the coast maintained a bearing of 201°–220° before branching out over the southeast Atlantic from 37° to 60°S and between 13°W and 16°E, traveling 3,800–8,200 km over the ensuing 53–110 d before transmissions ceased. Their locations were categorized as migrating or nonmigrating based on the relative orientation of the track and net speed. An average of 42% of nonmigrating locations were between 37°S and 45°S, and 53% were south of 52°S, possibly associated with the Subtropical Convergence and Antarctic Polar Front, respectively. Whaling data suggest right whales fed largely on copepods at the former and euphausiids at the latter. If the nonmigrating locations represented feeding at these frontal zones, switching between them would seem to have obvious cost‐benefit implications.