Elucidation of the speciation history of three sister species of crown-of-thorns starfish (Acanthaster spp.) based on genomic analysis

The crown-of-thorns starfish (COTS) is a coral predator that is widely distributed in Indo-Pacific Oceans. A previous phylogenetic study using partial mitochondrial sequences suggested that COTS had diverged into four distinct species, but a nuclear genome-based analysis to confirm this was not conducted. To address this, COTS species nuclear genome sequences were analysed here, sequencing Northern Indian Ocean (NIO) and Red Sea (RS) species genomes for the first time, followed by a comparative analysis with the Pacific Ocean (PO) species. Phylogenetic analysis and ADMIXTURE analysis revealed clear divergences between the three COTS species. Furthermore, within the PO species, the phylogenetic position of the Hawaiian sample was further away from the other Pacific-derived samples than expected based on the mitochondrial data, suggesting that it may be a PO subspecies. The pairwise sequentially Markovian coalescent model showed that the trajectories of the population size diverged by region during the Mid-Pleistocene transition when the sea-level was dramatically decreased, strongly suggesting that the three COTS species experienced allopatric speciation. Analysis of the orthologues indicated that there were remarkable genes with species-specific positive selection in the genomes of the PO and RS species, which suggested that there may be local adaptations in the COTS species.     

Genetic differentiation and inferred dynamics of a hybrid zone between Northern Spotted Owls (Strix occidentalis caurina) and California Spotted Owls (S. o. occidentalis) in northern California

Genetic differentiation among Spotted Owl (Strix occidentalis) subspecies has been established in prior studies. These investigations also provided evidence for introgression and hybridization among taxa but were limited by a lack of samples from geographic regions where subspecies came into close contact. We analyzed new sets of samples from Northern Spotted Owls (NSO: S. o. caurina) and California Spotted Owls (CSO: S. o. occidentalis) in northern California using mitochondrial DNA sequences (mtDNA) and 10 nuclear microsatellite loci to obtain a clearer depiction of genetic differentiation and hybridization in the region. Our analyses revealed that a NSO population close to the northern edge of the CSO range in northern California (the NSO Contact Zone population) is highly differentiated relative to other NSO populations throughout the remainder of their range. Phylogenetic analyses identified a unique lineage of mtDNA in the NSO Contact Zone, and Bayesian clustering analyses of the microsatellite data identified the Contact Zone as a third distinct population that is differentiated from CSO and NSO found in the remainder of the subspecies' range. Hybridization between NSO and CSO was readily detected in the NSO Contact Zone, with over 50% of individuals showing evidence of hybrid ancestry. Hybridization was also identified among 14% of CSO samples, which were dispersed across the subspecies' range in the Sierra Nevada Mountains. The asymmetry of hybridization suggested that the hybrid zone may be dynamic and moving. Although evidence of hybridization existed, we identified no F1 generation hybrid individuals. We instead found evidence for F2 or backcrossed individuals among our samples. The absence of F1 hybrids may indicate that (1) our 10 microsatellites were unable to distinguish hybrid types, (2) primary interactions between subspecies are occurring elsewhere on the landscape, or (3) dispersal between the subspecies' ranges is reduced relative to historical levels, potentially as a consequence of recent regional fires.     

C-reactive protein binds to the 3beta-OH group of cholesterol in LDL particles

C-reactive protein (CRP) has been suggested to contribute to the development of atherosclerosis. We previously found binding of CRP to cholesterol in modified low density lipoprotein (LDL) particles. Here, we characterize the interaction between CRP and cholesterol in more detail. When lipids of native LDL were separated by thin-layer chromatography, CRP bound only to cholesterol. When various cholesterol analogues were compared for their ability to bind CRP, we found that any modification of the 3beta-OH group blocked binding of CRP to cholesterol. Similarly, enrichment of LDL with cholesterol but not with its analogues triggered the binding of CRP to LDL. Finally, with the aid of anti-CRP monoclonal antibodies and by molecular modeling, we obtained evidence for involvement of the phosphorylcholine-binding site of CRP in cholesterol binding. Thus, CRP can bind to cholesterol, and the interaction is mediated by the phosphorylcholine-binding site of CRP and the 3beta-hydroxyl group of cholesterol.     

Obesity and labour market success in Finland: The difference between having a high BMI and being fat

This paper examines the relationship between obesity and labour market success in Finland, using various indicators of individual body composition along with body mass index (BMI). Weight, height, fat mass and waist circumference are measured by health professionals. We find that only waist circumference has a negative association with wages for women, whereas no obesity measure is significant in the linear wage models for men. However, all measures of obesity are negatively associated with women's employment probability and fat mass is negatively associated with men's employment probability. We also find that the use of categories for waist circumference and fat mass has a substantial influence on the results. For example, the category for high fat mass is associated with roughly 5.5% lower wages for men. All in all, the results indicate that in the absence of measures of body composition, there is a risk that labour market penalties associated with obesity are measured with bias.     

Motor unit recruitment in the trapezius muscle with special reference to coarse arm movements.

Chronic shoulder pain is common in a variety of occupations. The "Cinderella hypothesis" suggests that the pain originates from damaged type I muscle fibres driven into degenerative processes as a result of too long activation and too short recovery time. The main purpose of this study was to investigate if the same motor units are active during all phases of coarse arm movements. Eight healthy volunteers participated in the study. Intramuscular electromyographic signals were picked up with a four-lead fine wire electrode, during a unilateral straight arm movement. The movement started with either (part 1) an abduction or a flexion, then (2) a movement in the horizontal plane from the sagittal to the frontal plane or vice versa, and finally (3) an adduction or an extension to the start position. The movement cycle was performed in three different speeds, slow, medium, and high, with one, two or five cycles per 20 s, respectively. On an average, the motor unit action potentials (MUAPs) of 6 motor units (range, 1-15) were identified per trail. In total 94% of the MUAP trains that were identified showed firings in all 3 parts of the movements. The findings support the Cinderella hypothesis, although there is a need to further investigate the temporal pattern of long-term motor unit activity.     

Effect of prolonged ethanol ingestion on hepatic lipogenesis and related enzyme activities

1. Hepatic lipogenesis in vivo and the activities of enzymes associated with fatty acid synthesis in the liver were studied in rats fed for 21 days on liquid diets containing ethanol. 2. The ethanol-fed rats developed a moderate hepatic triacylglycerol accumulation during this period. When carbohydrate was replaced by ethanol in the diet, the rate of fatty acid synthesis was slower in the ethanol-fed rats on low-, medium- and high-fat diets than in the appropriate controls. However, when the fat/carbohydrate ratio was kept the same in the ethanol-fed and control rats, ethanol had no influence on the rate of fatty acid synthesis. 3. Glucose 6-phosphate dehydrogenase activity was lower in the ethanol-fed group. ;Malic' enzyme activity did not change during the ethanol treatment when the fat/carbohydrate ratio was kept unchanged. 4. The ATP citrate lyase activity was lower in the ethanol-fed rats on all diets, whereas acetyl-CoA synthetase activity was independent of the composition of the control diet, but was lower in the ethanol-fed rats, in which the concentration of the active form of pyruvate dehydrogenase was also lower. 5. It is concluded that hepatic fatty acid synthesis does not play any major role in ethanol-induced triacylglycerol accumulation. Careful design of the diets is necessary to reveal the specific effects of ethanol on the enzymes associated with lipogenesis.     

Musa chunii Hakkinen, a new species (Musaceae) from Yunnan,China and taxonomic identity of Musa rubra

The center of diversity of the genus Musa (Musaceae) is in Southeast Asia, a region not studied in detail and where new species and varieties continue to be reported. A new wild banana species, M. chunii Hakki-nen from Yunnan, China is described and illustrated based on observed morphological characteristics in the field. This extremely rare new species was only found in Tongbiguan Nature Reserve, Dehong District, West Yunnan. A key to M. chunii and related taxa is provided. In addition, critical notes regarding M. rubra Kurz identity are given.     

Aging, muscle fiber type, and contractile function in sprint-trained athletes.

Biopsy samples were taken from the vastus lateralis of 18- to 84-yr-old male sprinters (n = 91). Fiber-type distribution, cross-sectional area, and myosin heavy chain (MHC) isoform content were identified using ATPase histochemistry and SDS-PAGE. Specific tension and maximum shortening velocity (V(o)) were determined in 144 single skinned fibers from younger (18-33 yr, n = 8) and older (53-77 yr, n = 9) runners. Force-time characteristics of the knee extensors were determined by using isometric contraction. The cross-sectional area of type I fibers was unchanged with age, whereas that of type II fibers was reduced (P < 0.001). With age there was an increased MHC I (P < 0.01) and reduced MHC IIx isoform content (P < 0.05) but no differences in MHC IIa. Specific tension of type I and IIa MHC fibers did not differ between younger and older subjects. V(o) of fibers expressing type I MHC was lower (P < 0.05) in older than in younger subjects, but there was no difference in V(o) of type IIa MHC fibers. An aging-related decline of maximal isometric force (P < 0.001) and normalized rate of force development (P < 0.05) of knee extensors was observed. Normalized rate of force development was positively associated with MHC II (P < 0.05). The sprint-trained athletes experienced the typical aging-related reduction in the size of fast fibers, a shift toward a slower MHC isoform profile, and a lower V(o) of type I MHC fibers, which played a role in the decline in explosive force production. However, the muscle characteristics were preserved at a high level in the oldest runners, underlining the favorable impact of sprint exercise on aging muscle.     

Eukaryotic protein production in designed storage organelles

Background  

Protein bodies (PBs) are natural endoplasmic reticulum (ER) or vacuole plant-derived organelles that stably accumulate large amounts of storage proteins in seeds. The proline-rich N-terminal domain derived from the maize storage protein γ zein (Zera) is sufficient to induce PBs in non-seed tissues of Arabidopsis and tobacco. This Zera property opens up new routes for high-level accumulation of recombinant proteins by fusion of Zera with proteins of interest. In this work we extend the advantageous properties of plant seed PBs to recombinant protein production in useful non-plant eukaryotic hosts including cultured fungal, mammalian and insect cells.