Targeting and Function of the Mitochondrial Fission Factor GDAP1 Are Dependent on Its Tail-Anchor

Proteins controlling mitochondrial dynamics are often targeted to and anchored into the mitochondrial outer membrane (MOM) by their carboxyl-terminal tail-anchor domain (TA). However, it is not known whether the TA modulates protein function. GDAP1 is a mitochondrial fission factor with two neighboring hydrophobic domains each flanked by basic amino acids (aa). Here we define GDAP1 as TA MOM protein. GDAP1 carries a single transmembrane domain (TMD) that is, together with the adjacent basic aa, critical for MOM targeting. The flanking N-terminal region containing the other hydrophobic domain is located in the cytoplasm. TMD sequence, length, and high hydrophobicity do not influence GDAP1 fission function if MOM targeting is maintained. The basic aa bordering the TMD in the cytoplasm, however, are required for both targeting of GDAP1 as part of the TA and GDAP1-mediated fission. Thus, this GDAP1 region contains critical overlapping motifs defining intracellular targeting by the TA concomitant with functional aspects

High-Throughput Sequencing of RNA Silencing-Associated Small RNAs in Olive (Olea europaea L.)

Small RNAs (sRNAs) of 20 to 25 nucleotides (nt) in length maintain genome integrity and control gene expression in a multitude of developmental and physiological processes. Despite RNA silencing has been primarily studied in model plants, the advent of high-throughput sequencing technologies has enabled profiling of the sRNA component of more than 40 plant species. Here, we used deep sequencing and molecular methods to report the first inventory of sRNAs in olive (Olea europaea L.). sRNA libraries prepared from juvenile and adult shoots revealed that the 24-nt class dominates the sRNA transcriptome and atypically accumulates to levels never seen in other plant species, suggesting an active role of heterochromatin silencing in the maintenance and integrity of its large genome. A total of 18 known miRNA families were identified in the libraries. Also, 5 other sRNAs derived from potential hairpin-like precursors remain as plausible miRNA candidates. RNA blots confirmed miRNA expression and suggested tissue- and/or developmental-specific expression patterns. Target mRNAs of conserved miRNAs were computationally predicted among the olive cDNA collection and experimentally validated through endonucleolytic cleavage assays. Finally, we use expression data to uncover genetic components of the miR156, miR172 and miR390/TAS3-derived trans-acting small interfering RNA (tasiRNA) regulatory nodes, suggesting that these interactive networks controlling developmental transitions are fully operational in olive

The Transcriptome Analysis of Strongyloides stercoralis L3i Larvae Reveals Targets for Intervention in a Neglected Disease

BackgroundStrongyloidiasis is one of the most neglected diseases distributed worldwide with endemic areas in developed countries, where chronic infections are life threatening. Despite its impact, very little is known about the molecular biology of the parasite involved and its interplay with its hosts. Next generation sequencing technologies now provide unique opportunities to rapidly address these questions.Principal FindingsHere we present the first transcriptome of the third larval stage of S. stercoralis using 454 sequencing coupled with semi-automated bioinformatic analyses. 253,266 raw sequence reads were assembled into 11,250 contiguous sequences, most of which were novel. 8037 putative proteins were characterized based on homology, gene ontology and/or biochemical pathways. Comparison of the transcriptome of S. strongyloides with those of other nematodes, including S. ratti, revealed similarities in transcription of molecules inferred to have key roles in parasite-host interactions. Enzymatic proteins, like kinases and proteases, were abundant. 1213 putative excretory/secretory proteins were compiled using a new pipeline which included non-classical secretory proteins. Potential drug targets were also identified.ConclusionsOverall, the present dataset should provide a solid foundation for future fundamental genomic, proteomic and metabolomic explorations of S. stercoralis, as well as a basis for applied outcomes, such as the development of novel methods of intervention against this neglected parasite

Evolució de components bioquímics de la figa ("Ficus carica", varietat "Coll de dama") durant la maduració

S'ha estudiat l'evolució bioquímica de la matèria seca, amplada i llargada del fruit, densitat aparent, activitat catalàsica, activitat peroxidàsica, acidesa, proteïna, greix, composició en àcids grassos, àcid clorogènic, fibra, antocians, sucres reductors, disacàrids no reductors i midó, des de l'aparició del fruit a l'arbre fins que aquest va arribar a l'estadi de sobremaduració. L'evolució mostra una disminució de l'activitat catalàsica, activitat peroxidàsica, proteïna, àcid clorogènic, fibra i àcids grassos saturats i un increment de la matèria seca, amplada, llargada, densitat aparent, acidesa, greix, àcids grassos insaturats, antocians, sucres reductors i midó. Els disacàrids no reductors augmenten contínuament fins a arribar a la sobremaduració, moment en què disminueixen.The evolution of several parameters of fig fruits have been evaluated during the growing season and ripening. The evolution decreased in catalase activity, peroxidase activity, protein, chlorogenic acid, fibre and saturated fatty acids. The evolution increased in dry matter, transverse diameter, height fruits, apparent density, titratable acidity, fat content, insaturated fatty acids, anthocyanin, reducing sugar and starch. Sucrose increased up to the start of ripening and then declined.Se ha estudiado la evolución bioquímica de la materia seca, anchura y altura del fruto, densidad aparente, actividad catalásica, actividad peroxidásica, acidez, proteína, grasa, composición en ácidos grasos, ácido clorogénico, fibra, antocianos, azúcares reductores, disacáridos no reductores y almidón, desde la aparición del fruto en el árbol hasta que éste llegó al estadio de sobremaduración. La evolución muestra una disminución de la actividad catalásica, actividad peroxidásica, proteína, ácido clorogénico, fibra y ácidos grasos satura- dos y un incremento de la materia seca, anchura, altura, densidad aparente, acidez, grasa, ácidos grasos insaturados, antocianos, azúcares reductores y almidón. Los disacáridos no reductores aumentan continuamente hasta llegar a la sobremaduración, momento en que disminuyen

Morfología y anatomía del género Androcymbium (Colchicaceae) en Suráfrica Occidental

17 pages, 8 figures, 3 tables.[EN] Morphologicai and anatomical leaf studies were made in 32 populations belonging to 17 laxa of the genus Androcymbium in Southwest Africa. The morphological characters studied were corm and tunic characteristics, and number, distribution, shape, size, section, and color of leaves and bracts. The micromorphological characters were the leaf indument on both surface and margin, shape and size of epidermic cells, type md amount of stomata. Finally, the anatomical characters were mesophyll cell types, epidermic cell sizes, cellular wall types, size of central epidermic cells related to the other epidermic cells, and amount of idioblasts. The results showed a great heterogeneity in almost all characters analyzed. However, macromorphological characteristics related to color and shape of leaves and braets in the genus Androcymbium could be used as indicators of taxonomic afinities among species. Conversely, the micromorphological and anatomical characteristics studied showed a great variation of types that does not agree with the interspecific relationships established from morphological, allozymatic or cpDNA RFLP data in other research carried out within the genus.[ES] Se realizaron estudios morfológicos y anatómicos de las partes vegetativas en 32 poblaciones pertenecientes a 17 taxones del género Androcymbium en Suráfrica Occidental. Los caracteres morfológicos estudiados fueron las características del cormo y de las túnicas. y número. distribución. forma, tamaño. sección. y color de las hojas y brácteas. Los caracteres micromorfológicos estudiados fueron el indumento en la superficie y margen de la hoja. forma y tamaño de las células epidérmicas, y tipo y cantidad de estomas. Finalmente. los caracteres anatómicos fueron el tipo de células del mesofilo, tamaño de las células epidérmicas, tipo de pared celular, tamaño de las células epidérmicas centrales comparado con el resto de células de la lámina y cantidad de idioblastos. Los resultados mostraron una gran heterogeneidad en la mayoría de los caracteres analizados. A pesar de ello, algunas características macromorfológicas relacionadas con el color y forma de las hojas y braceas en el género Androcymbium. podrían ser utilizadas como indicadores taxonómicos de afinidades entre especies. Contrariamente, las características micromorfológicas y anatómicas estudiadas mostraron una gran variedad de formas que no se ajustan a las relaciones entre especies establecidas previamente a partir de datos de morfología, aloenzimas o RFLPs del cpDNA.The Karl faust Foundation granted the economic support for this investigation.Peer reviewe

Pollen morphology and biometry of the genus <i>Androcymbium</i> (Colchicaceae) in southern Africa: taxonomic and biogeographic considerations

Pollen characters in 16 southern African type specimens of Androcymbium Willd. that represent the three sections into which the genus is presently divided (Androcymbium,  Dregeocymbium and  Erythrostictus), were examined to assess the possibility of sectional characterization based on pollen traits and to explore the relationship between pollen traits and geo­graphic species distribution. Differences in pollen grain size, shape, number of apertures and exine pattern, were observed. Principal Component Analysis, using both qualitative and biometric pollen characters, distinguished four groups of species with four different pollen types. Most of the species have a microreticulate exine pattern with either diaperturate or tria- perturate grains. The remaining species have either a rugulate exine pattern with diaperturate grains, or a rugulate-reticu- late exine pattern with thickened (hypertrophied) muri with diaperturate grains. While section Dregeocymbium can be well delimited by the unique thickened muri. and by a significantly larger grain size, no diagnostic pollen traits were found for sections Androcymbium and  Erythrostictus. Similarly, although the six northern African species exhibit a microreticulate exine pattern, the high variability observed for this trait in their southern African counterparts, does not follow a geographic pattern