Bacterial mode of replication with eukaryotic-like machinery in a hyperthermophilic archaeon

Despite a rapid increase in the amount of available archaeal sequence information, little is known about the duplication of genetic material in the third domain of life. We identified a single origin of bidirectional replication in Pyrococcus abyssi by means of in silico analyses of cumulative oligomer skew and the identification of an early replicating chromosomal segment. The replication origin in three Pyrococcus species was found to be highly conserved, and several eukaryotic-like DNA replication genes were clustered around it. As in Bacteria, the chromosomal region containing the replication terminus was a hot spot of genome shuffling. Thus, although bacterial and archaeal replication proteins differ profoundly, they are used to replicate chromosomes in a similar manner in both prokaryotic domains.     

Carboxyl terminal domain of Gs alpha specifies coupling of receptors to stimulation of adenylyl cyclase

The alpha subunits of Gs and Gi link different sets of hormone receptors to stimulation and inhibition, respectively, of adenylyl cyclase. A chimeric alpha i/alpha s cDNA was constructed that encodes a polypeptide composed of the amino terminal 60% of an alpha i chain and the carboxyl terminal 40% of alpha s. The cDNA was introduced via a retroviral vector into S49 cyc- cells, which lack endogenous alpha s. Although less than half of the hybrid alpha chain is derived from alpha s, its ability to mediate beta-adrenoceptor stimulation of adenylyl cyclase matched that of the normal alpha s polypeptide expressed from the same retroviral vector in cyc- cells. This result indicates that carboxyl terminal amino acid sequences of alpha s contain the structural features that are required for specificity of interactions with the effector enzyme, adenylyl cyclase, as well as with the hormone receptor.     

Linking coastal aquaculture of meagre Argyrosomus regius and Western Mediterranean coastal fisheries through escapes incidents

Escape incidents in coastal aquaculture lead to economic losses for farmers and may have indirect socio‐economic effects on local fisheries. In this study, the relationship of meagre, Argyrosomus regius (Asso), production in open‐sea cages and coastal small‐scale fisheries was analysed through captures of escapes, which are easily detected because this species is considered locally absent in native communities in Western Mediterranean regions. Scale reading showed that 100% of captured meagre were escapees. The existence of a direct relationship, in terms of biomass, between the development of meagre coastal aquaculture and the increase of captures of this species by local fisheries was demonstrated. The spatial distribution of meagre captures suggested that there is a local environmental and economic interaction between meagre aquaculture and fisheries through escapees. Monitoring the presence of locally absent species such as meagre within landings might help to assess the magnitude of escapes, the potential economic effects on local aquaculture and fishery industries, and the potential adverse ecological impacts on local ecosystems.     

Climate‐driven winter variations of Calanus sinicus abundance in the East China Sea

Global environmental changes threaten the sustainable use of resources and raise uncertainties regarding marine populations' responses in a changing Ocean. The pelagic copepods of the genus Calanus play a central role in shelf ecosystems transferring phytoplankton carbon to harvested populations, from boreal to temperate regions. Here we examined a 15‐yr time series of Calanus sinicus abundance in regards to climate forcing in the East China Sea. We identified a compound effect of the Pacific Decadal Oscillation (PDO) and the East Asian Winter Monsoon (EAWM) on environmental conditions in the East China Sea. Such climate influences not only a southward transport of C. sinicus from its population centres into the Taiwan area, but favours advantageous thermal conditions for the species as well. On the interannual scale, our results show that the population size of C. sinicus echoes climate‐driven temperature changes. Hence, the possibility of using the PDO and EAWM variability for assessing and predicting interannual abundance changes of C. sinicus in the East China Sea is considered. The observed close relationship between climate and C. sinicus may promote bottom‐up controls in the pelagic food web, further influencing the southern edge of the species' geographic distribution. Owing to the prominent role this species plays in food web dynamics these results might help integrative fisheries management policies in the heavily exploited East China Sea.     

State of the art: Stem cells in equine regenerative medicine

According to Greek mythology, Prometheus' liver grew back nightly after it was removed each day by an eagle as punishment for giving mankind fire. Hence, contrary to popular belief, the concept of tissue and organ regeneration is not new. In the early 20th century, cell culture and ex vivo organ preservation studies by Alexis Carrel, some with famed aviator Charles Lindbergh, established a foundation for much of modern regenerative medicine. While early beliefs and discoveries foreshadowed significant accomplishments in regenerative medicine, advances in knowledge within numerous scientific disciplines, as well as nano‐ and micromolecular level imaging and detection technologies, have contributed to explosive advances over the last 20 years. Virtually limitless preparations, combinations and applications of the 3 major components of regenerative medicine, namely cells, biomaterials and bioactive molecules, have created a new paradigm of future therapeutic options for most species. It is increasingly clear, however, that despite significant parallels among and within species, there is no ‘one‐size‐fits‐all’ regenerative therapy. Likewise, a panacea has yet to be discovered that completely reverses the consequences of time, trauma and disease. Nonetheless, there is no question that the promise and potential of regenerative medicine have forever altered medical practices. The horse is a relative newcomer to regenerative medicine applications, yet there is already a large body of work to incorporate novel regenerative therapies into standard care. This review focuses on the current state and potential future of stem cells in equine regenerative medicine.