Effects of Power Lines on Area Use and Behaviour of Semi-Domestic Reindeer in Enclosures

We conducted large-scale, replicated experiments to test the effects of two parallel power lines on area use, behaviour, and activity of semidomestic reindeer in enclosures. Yearling female reindeer were released into four 50×400 m enclosures; two treatment enclosures with power lines and two control enclosures. Reindeer from two herds, one from Kautokeino (domestic tame) and one from Vågå, (domestic wild) were tested separately and compared. Individual location within the enclosures was not affected by the power lines. Effects on restless behaviour were ambiguous, with slightly more restless behaviour in the treatment enclosures for the domestic tame reindeer, while the domestic wild reindeer maintained a stable level in the treatment enclosures, increasing with time in the control enclosures. Activity changes were slightly more common among animals within treatment enclosures for both herds, with no indication of habituation during the experiment. The domestic wild reindeer had more than three times the amount of restless behaviour than the domestic tame reindeer. Our study indicates that for reindeer in enclosures, the disturbance from a power line construction is negligible. This suggests that power lines are a minor disturbing factor compared to human handling when using fenced in areas like grazing gardens in reindeer husbandry

Structure of full-length human phenylalanine hydroxylase in complex with tetrahydrobiopterin

6 pags., 3 figs.Phenylalanine hydroxylase (PAH) is a key enzyme in the catabo-lism of phenylalanine, and mutations in this enzyme cause phenylketonuria (PKU), a genetic disorder that leads to brain damage and mental retardation if untreated. Some patients benefit from supplementation with a synthetic formulation of the cofactor tetrahydrobiopterin (BH) that partly acts as a pharmacological chaperone. Here we present structures of full-length human PAH (hPAH) both unbound and complexed with BH in the precatalytic state. Crystal structures, solved at 3.18-Å resolution, show the interactions between the cofactor and PAH, explaining the negative regulation exerted by BH. BH forms several H-bonds with the N-terminal autoregulatory tail but is far from the catalytic Fe. Upon BH binding a polar and salt-bridge interaction network links the three PAH domains, explaining the stability conferred by BH. Importantly, BH binding modulates the interaction between subunits, providing information about PAH allostery. Moreover, we also show that the cryo-EM structure of hPAH in absence of BH reveals a highly dynamic conformation for the tetramers. Structural analyses of the hPAH:BH subunits revealed that the substrate-induced movement of Tyr138 into the active site could be coupled to the displacement of BH from the precatalytic toward the active conformation, a molecular mechanism that was supported by site-directed mutagenesis and targeted molecular dynamics simulations. Finally, comparison of the rat and human PAH structures show that hPAH is more dynamic, which is related to amino acid substitutions that enhance the flexibility of hPAH and may increase the susceptibility to PKU-associated mutations.The work was supported by grants from the MICINN Spanish Ministry of Research, Innovation & Universities BFU2017-90030-P (to J.A.H.) and BFU2017-87316 (to R.F.-L.); programs Forny (248889/O30) and FRIMEDBIO (261826) from the Research Council of Norway (to A.M.); the Western Norway Regional Health Authorities (Helse Vest Projects 911959 to M.I.F. and 912246 to A.M.); and the K.G. Jebsen foundation (to M.I.F. and A.M.), the staff from ALBA synchrotron facility (Barcelona) and the European Synchrotron Radiation Facility (ESRF

The structure of full-length human phenylalanine hydroxylase in complex with tetrahydrobiopterin

Joint 12th EBSA congress / 10th ICBP – IUPAP congress: Biophysics for life and technology, Madrid, Spain, July 20-24, 2019. -- http://www.ebsa2019.org/Peer reviewe