The discovery of the 2-C-methyl-d-erythritol-4-phosphate pathway for the biosynthesis of isoprenoids raises the important question of the nature and regulation of the enzymes involved in this pathway. CLA1, a gene previously isolated from Arabidopsis, encodes the first enzyme of the 2-C-methyl-d-erythritol-4-phosphate pathway, 1-deoxy-d-xylulose-5-phosphate synthase. We demonstrate this enzyme activity by complementation of the cla1-1 mutant phenotype and by direct enzymatic assays. Based on mRNA and protein expression patterns this enzyme is expressed mainly in developing photosynthetic and non-photosynthetic tissues. The ␤-glucuronidase expression pattern driven from the CLA1 gene regulatory region supports the northern and protein data while also showing that this gene has some level of expression in most tissues of the plant. A mutation in the CLA1 gene interferes with the normal development of chloroplasts and etioplasts, but does not seem to affect amyloplast structure. Microscopic analysis also shows a pleiotropic effect of the CLA1 gene mutation in mesophyll tissue formation.In higher plants isoprenoids are derived from isopentenyl diphosphate (IPP) and synthesized in at least two different compartments, the cytoplasm and the chloroplast. For a long time it was assumed that IPP was synthesized exclusively by the mevalonate pathway in all organisms (Spurgeon and Porter, 1981; Goldstein and Brown, 1990). However, independent studies have demonstrated that in eubacteria, green algae, and plants, IPP is also synthesized by a non-mevalonate pathway designated as the 2-Cmethyl-d-erythritol-4-P (MEP) pathway (for review, see Rohmer, 1998Rohmer, , 1999Lichtenthaler, 1999). Thus in plants cytosolic IPP is synthesized by the mevalonate pathway and plastidic IPP is synthesized by the MEP pathway (Lichtenthaler, 1999). In the MEP pathway IPP is synthesized from pyruvate and glyceraldehyde-3-P via novel intermediates (Rohmer et al

Mitochondrial targeted manganese superoxide dismutase is a major antioxidant enzyme, the levels of which modulate the response of cells, tissues and organs to ionizing irradiation. We developed a Tet-regulated MnSOD mouse (MnSODtet) to examine the detailed relationship between cellular MnSOD concentration and radioresistance and carried out in vitro studies using bone marrow culture derived stromal cell lines (mesenchymal stem cells). Homozygous MnSODtet/tet cells had low levels of MnSOD, reduced viability and proliferation, increased radiosensitivity, elevated overall antioxidant stores, and defects in cell proliferation and DNA strand-break repair. Doxycycline (doxy) treatment of MnSODtet/tet cells increased MnSOD levels and radioresistance from ñ of 2.79 ± 1.04 to 8.69 ± 1.09 (P = 0.0060) and normalized other biologic parameters. In contrast, MnSODtet/tet cells showed minimal difference in baseline and radiation induced mRNA and protein levels of TGF-β, Nrf2 and NF-κB and radiation induced cell cycle arrest was not dependent upon MnSOD level. These novel MnSODtet/tet mouse derived cells should be valuable for elucidating several parameters of the oxidative stress response to ionizing radiation.

Within this contribution we introduce a 3D-printed cartridge system enabling the convenient and cost-efficient sample preparation from sputum for subsequent PCR based detection schemes. The developed fluidic system operates is...

Summary Seabirds are highly threatened, including by fisheries bycatch. Accurate understanding of offshore distribution of seabirds is crucial to address this threat. Tracking technologies revolutionised insights into seabird distributions but tracking data may contain a variety of biases. We tracked two threatened seabirds (Salvin’s Albatross Thalassarche salvini n = 60 and Black Petrel Procellaria parkinsoni n = 46) from their breeding colonies in Aotearoa (New Zealand) to their non-breeding grounds in South America, including Peru, while simultaneously completing seven surveys in Peruvian waters. We then used species distribution models to predict occurrence and distribution using either data source alone, and both data sources combined. Results showed seasonal differences between estimates of occurrence and distribution when using data sources independently. Combining data resulted in more balanced insights into occurrence and distributions, and reduced uncertainty. Most notably, both species were predicted to occur in Peruvian waters during all four annual quarters: the northern Humboldt upwelling system for Salvin’s Albatross and northern continental shelf waters for Black Petrels. Our results highlighted that relying on a single data source may introduce biases into distribution estimates. Our tracking data might have contained ontological and/or colony-related biases (e.g. only breeding adults from one colony were tracked), while our survey data might have contained spatiotemporal biases (e.g. surveys were limited to waters <200 nm from the coast). We recommend combining data sources wherever possible to refine predictions of species distributions, which ultimately will improve fisheries bycatch management through better spatiotemporal understanding of risks.

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Con el objetivo de determinar los principales parámetros poblacionales de la tortuga verde del Pacifico este (Chelonia mydasagassizii) el Instituto del Mar del Perú (IMARPE), mediante el Laboratorio Costero de Pisco, a partir del 2010 empezó las investigaciones biológicas en tortugas marinas, a través de monitoreos acuáticos en la ensenada de la Aguada, en Bahía Paracas, Pisco. Durante el periodo 2010- 2017 se determinó el largo curvo del caparazón (LCC), presentando promedio de 58,4 ± 7,9 cm (rango: 40,9 - 84,5 cm, n=438) con 88,7% de juveniles y 11,3% de sub-adultos. Estas tallas son las menores registradas en el Pacifico este para la especie. El número promedio de tortugas capturadas por km de red tendida por hora fue 1,03 ±1,23 (rango: 0 - 5,9, n=83). Los principales epibiontes capturados fueron de origen costero - nerítico: Platylepas hexastylos (40,5%, n=570), Stephanolepas muricata (13,4%, n=189), Conchoderma virgatum (13,1%, n=184), Ozobranchus margoi (12,9%, n=181), Chelonibia testudinaria (10,3%, n=145), y también de origen pelágico – oceánico: Lepas anatifera (8,5%, n=120), Planes cyaneus(0,8%, n=11) y Remora remora (0,6%, n=7). Se evidencia la gran importancia de Paracas como una exclusiva zona de reclutamiento desde zonas oceánicas. Durante lo que va del proyecto (2010 – 2017) se realizaron 46 recapturas, de las cuales 41 fueron juveniles y 5 sub-adultos, también se reportaron 5 triples recapturas (todos juveniles). La residencia en el área, expresada en el número promedio de días utilizados por la especie en el área de alimentación fue de 306,2 ± 166,9 días (rango: 170 - 708, n=26), la tasa de crecimiento fue de 7,4 ± 2,8 cm/año (rango: 2,0 – 11,7, n=26), ambos análisis se realizaron considerando recapturas mayores a 170 días. El índice de condición corporal (BCI) promedio por año y por estadio fue mayor en juveniles (1,49) con respecto a los sub-adultos (1,43). La mayoría de los parámetros poblacionales fueron favorables, lasaltas tasas de crecimiento y de BCI en conjunto con las bajas tasas de recapturas demuestran que esta es una población grande, saludable y con posibles bajos niveles de endogamia. Paradójicamente es preocupante que aun subsistan capturas incidentales y dirigidas en la zona, por lo que son necesarias y urgentes las medidas de conservación y fiscalización en la zona de Pisco - Paracas.

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El presente trabajo detalla la información mensual de la avifauna que se realizó en doce playas de la Reserva Nacional de San Fernando (RNSF) (UTM 500944,50 m S, 1643478,24 m O) de junio 2018 a mayo 2019. A lo largo del año de evaluación se registró 19 familias divididas en 29 especies de aves, de las cuales 24 corresponden al grupo de aves marinas y cinco a los ambientes terrestres; las más abundantes fueron Larosterna inca (Lesson, 1827) (18,68ind./m) y Sula variegata (Tschudi, 1843) (5,24 ind./m). La llegada de ciertas aves migratorias entre primavera 2018 y otoño 2019 podría tener efecto en la composición y abundancia de especies en las playas evaluadas, existiendo alta similaridad (73%) en las estaciones de verano – otoño y primavera - invierno. Finalmente, se debe resaltar que se observó evidencias reproductivas de algunas especies como: pingüino de Humboldt, chuita, cushuri, piquero peruano, gaviota peruana, zarcillo y el aguilucho variable, especies residentesregistradas en la RNSF.