Two distinct conformers of PrPD type 1 of sporadic Creutzfeldt–Jakob disease with codon 129VV genotype faithfully propagate in vivo

Current classifications of sporadic Creutzfeldt–Jakob disease (sCJD) identify five subtypes associated with different disease phenotypes. Most of these histopathological phenotypes (histotypes) co-distribute with distinct pairings of methionine (M)/valine (V) genotypes at codon 129 of the prion protein (PrP) gene and the type (1 or 2) of the disease-associated PrP (PrPD). Types 1 and 2 are defined by the molecular mass (~ 21 kDa and ~ 19 kDa, respectively) of the unglycosylated isoform of the proteinase K-resistant PrPD (resPrPD). We recently reported that the sCJDVV1 subtype (129VV homozygosity paired with PrPD type 1, T1) shows an electrophoretic profile where the resPrPD unglycosylated isoform is characterized by either one of two single bands of ~ 20 kDa (T120) and ~ 21 kDa (T121), or a doublet of ~ 21–20 kDa (T121−20). We also showed that T120 and T121 in sCJDVV have different conformational features but are associated with indistinguishable histotypes. The presence of three distinct molecular profiles of T1 is unique and raises the issue as to whether T120 and T121 represent distinct prion strains. To answer this question, brain homogenates from sCJDVV cases harboring each of the three resPrPD profiles, were inoculated to transgenic (Tg) mice expressing the human PrP-129M or PrP-129V genotypes. We found that T120 and T121 were faithfully replicated in Tg129V mice. Electrophoretic profile and incubation period of mice challenged with T121−20 resembled those of mice inoculated with T121 and T120, respectively. As in sCJDVV1, Tg129V mice challenged with T121 and T120 generated virtually undistinguishable histotypes. In Tg129M mice, T121 was not replicated while T120 and T121−20 generated a ~ 21–20 kDa doublet after lengthier incubation periods. On second passage, Tg129M mice incubation periods and regional PrP accumulation significantly differed in T120 and T121−20 challenged mice. Combined, these data indicate that T121 and T120 resPrPD represent distinct human prion strains associated with partially overlapping histotypes.

Seed storage protein electrophoretic profile among popular cultivars of date palm (Phoenix dactylifera L.)

Evaluation of the seed storage protein electrophoretic profile among popular cultivars of date palm (Pheonix dactylifera) available in different regions of Balochistan, Pakistan was conducted. The genetic diversity of seed proteins of 12 cultivars were examined by electrophoresis. Twenty one protein bands with different mobility rates were identified within a molecular weight range of 11 to 351 KDa. The cultivar from Panjgur (Soorri) was well resolved on SDS-PAGE from the all other cultivars and gave the highest number of intense bands due to unique genetic build up. Genetic diversity among cultivars was evaluated by constructing the dendrogram for protein bands, which showed the cultivar (SP1) which is significantly different from all other cultivars on the basis of similarities in molecular weight of proteins.

Análisis electroforético de proteínas del veneno de Bothrops atrox “jergón” (Ofidia: Viperidae) de distintas zonas geográficas de la Amazonia Peruana

Análisis electroforético de proteínas del veneno de Bothrops atrox “jergón” (Ofidia: Viperidae) de distintas zonas geográficas de la Amazonia Peruana Electrophoretic analysis of proteins in the venom of Bothrops atrox “lancehead” (Ofidia: Viperidae) from different geographical zones to the Peruvian Amazon Rommel Rojas, Roberson Ramírez, Marianela Cobos y Juan Castro Centro de Investigaciones de Recursos Naturales-CIRNA Universidad Nacional de la Amazonia Peruana-UNAP. Apartado postal 496S Facultad de Ciencias Biológicas. DOI: https://doi.org/10.33017/RevECIPeru2011.0050/ RESUMEN Los venenos de serpientes son secreciones endógenas constituidas en su mayor parte por proteínas, que pueden causar diversos cuadros sintomatológicos, y en algunos casos la muerte. Las serpientes fueron recolectadas en el campo por muestreos herpetológicos utilizando la técnica del revelamiento por encuentros casuales [1] y el veneno recolectado por ordenamiento manual. Usando la técnica de electroforesis discontinua en gel de poliacrilamida [2] al 7.5% y 12% con dodecilsulfato de sodio (PAGE-SDS) se analizaron los perfiles electroforéticos de 5 especímenes de Bothrops atrox “jergón” provenientes de 5 zonas geográficas de la Amazonia Peruana, siendo evaluadas en condiciones reductoras utilizando veneno centrifugado, asimismo se realizó la cuantificación de las proteínas por el método espectrofotométrico utilizando el método de Biuret [3]. Los resultados muestran la presencia de proteínas en los rangos de 14 kD a 116 kD, obteniéndose variaciones en la cantidad de bandas proteínas, 9,11,8,7,8 para las poblaciones de Moena Caño, Isla Iquitos, Panguana, Genaro Herrera y Nina Rumi, mientras que la cuantificación muestra la existencia de una mayor cantidad de proteínas en el veneno de la serpiente proveniente de Isla Iquitos (67.41 mg/ml) y una menor cantidad en el espécimen de Genaro Herrera (32.13 mg/ml). Se concluye mencionando la existencia de variaciones en los perfiles electroforéticos y cantidades de las proteínas presentes en el veneno de Bothrops atrox de la Amazonia Peruana. Descriptores: venenos, proteínas, electroforesis, poliacrilamida, cuantificación. ABSTRACT The snake´s venoms are endogenous secretions constituted for proteins and can produce different symptomatology and in some cases the dead. Using the electrophoretic technique in polyacrylamide discontinuous gel of 7.5% and 12% whit sodium dodecylsulphate (PAGE-SDS) in reductions conditions were carried on a protein analysis of the venom in 5 Bothrops atrox snake´s from 5 different geographical zones to the Peruvian Amazon using centrifuge crude venom, additionally the proteins were quantification for using an spectrophotometer following the Biuret method. The results evidence the presents of different bands in the proteins, in ranges of 14 kD to 116 kD, finding 9, 11,8,7,8 bands of proteins for the populations of Moena Caño, Isla Iquitos, Panguana, Genaro Herrera and Nina Rumi, while the quantification show the presents to major quantity of protein in the snake from Isla Iquitos (67.41 mg/ml) and a less quantity in the specie from Genaro Herrera (32.13 mg/ml). We conclude mentioning the existence of variations in the electrophoretic profile and quantification to proteins from the venom of Bothrops atrox to the Peruvian Amazon. Keywords: venoms, proteins, electrophoretic, polyacrylamide, quantification.