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Additional Sequences (additional + sequence)
Selected AbstractsDigestive peptidases in Tenebrio molitor and possibility of use to treat celiac diseaseENTOMOLOGICAL RESEARCH, Issue 3 2007Elena N. ELPIDINA Abstract Digestion in Tenebrio molitor larvae occurs in the midgut, where there is a sharp pH gradient from 5.6 in the anterior midgut (AM) to 7.9 in the posterior midgut (PM). Accordingly, digestive enzymes are compartmentalized to the AM or PM. Enzymes in the AM are soluble and have acidic or neutral pH optima, while PM enzymes have alkaline pH optima. The main peptidases in the AM are cysteine endopeptidases presented by two to six subfractions of anionic proteins. The major activity belongs to cathepsin L, which has been purified and characterized. Serine post-proline cleaving peptidase with pH optimum 5.3 was also found in the AM. Typical serine digestive endopeptidases, trypsin-like and chymotrypsin-like, are compartmentalized to the PM. Trypsin-like activity is due to one cationic and three anionic proteinases. Chymotrypsin-like activity consists of one cationic and four anionic proteinases, four with an extended binding site. The major cationic trypsin and chymotrypsin have been purified and thoroughly characterized. The predicted amino acid sequences are available for purified cathepsin L, trypsin and chymotrypsin. Additional sequences for putative digestive cathepsins L, trypsins and chymotrypsins are available, implying multigene families for these enzymes. Exopeptidases are found in the PM and are presented by a single membrane aminopeptidase N-like peptidase and carboxypeptidase A, although multiple cDNAs for carboxypeptidase A were found in the AM, but not in the PM. The possibility of the use of two endopeptidases from the AM , cathepsin L and post-proline cleaving peptidase , in the treatment of celiac disease is discussed. [source] Phylogeographic structuring and volant mammals: the case of the pallid bat (Antrozous pallidus)JOURNAL OF BIOGEOGRAPHY, Issue 7 2007Sarah E. Weyandt Abstract Aim, To examine the phylogeographic pattern of a volant mammal at the continental scale. The pallid bat (Antrozous pallidus) was chosen because it ranges across a zone of well-studied biotic assemblages, namely the warm deserts of North America. Location, The western half of North America, with sites in Mexico, the United States, and Canada. Methods, PCR amplification and sequencing of the mitochondrial control region was performed on 194 pallid bats from 36 localities. Additional sequences at the cytochrome- b locus were generated for representatives of each control-region haplotype. modeltest was used to determine the best set of parameters to describe each data set, which were incorporated into analyses using paup*. Statistical parsimony and measurements of population differentiation (amova, FST) were also used to examine patterns of genetic diversity in pallid bats. Results, We detected three major lineages in the mitochondrial DNA of pallid bats collected across the species range. These three major clades have completely non-overlapping geographic ranges. Only 6 of 80 control-region haplotypes were found at more than a single locality, and sequences at the more conserved cytochrome- b locus revealed 37 haplotypes. Statistical parsimony generated three unlinked networks that correspond exactly to clades defined by the distance-based analysis. On average there was c. 2% divergence for the combined mitochondrial sequences within each of the three major clades and c. 7% divergence between each pair of clades. Molecular clocks date divergence between the major clades at more than one million years, on average, using the faster rates, and at more than three million years using more conservative rates of evolution. Main conclusions, Divergent haplotypic lineages with allopatric distributions suggest that the pallid bat has responded to evolutionary pressures in a manner consistent with other taxa of the American southwest. These results extend the conclusions of earlier studies that found the genetic structuring of populations of some bat species to show that a widespread volant species may comprise a set of geographically replacing monophyletic lineages. Haplotypes were usually restricted to single localities, and the clade showing geographic affinities to the Sonoran Desert contained greater diversity than did clades to the east and west. While faster molecular clocks would allow for glacial cycles of the Pleistocene as plausible agents of diversification of pallid bats, evidence from co-distributed taxa suggests support for older events being responsible for the initial divergence among clades. [source] Dead Birds Migrating: DVD Reinvigorates Classic Ethnographic FilmAMERICAN ANTHROPOLOGIST, Issue 3 2005JOHN BISHOP The DVD release of Robert Gardner's Dead Birds exemplifies the added value of extra features and the improvement in viewing quality when existing ethnographic films are distributed in this new medium. Whereas in the past, ethnographic films have been experienced as transitory performances, a nonlinear medium like DVD makes it possible to read a film the way one reads a book, stopping, reflecting, and reviewing. The inclusion of multiple soundtracks, additional sequences, and associated texts affords a density of content that has not previously been possible in either films or books. [source] Diverse genomic integration of a lentiviral vector developed for the treatment of Wiskott,Aldrich syndromeTHE JOURNAL OF GENE MEDICINE, Issue 8 2009Julie Mantovani Abstract Background The genomic integration of a lentiviral vector developed for the treatment of Wiskott,Aldrich syndrome (WAS) was assessed by localizing the vector insertion sites (IS) in a murine model of gene therapy for the disease. Methods Transduced hematopoietic progenitor cells were transplanted into mice or cultured in vitro. The IS were determined in the genomic DNA from blood, the bone marrow of the animals and from cultured cells. Results Sequencing vector,genomic DNA junctions yielded more than 150 IS of which 50,70% were located in transcription units. To obtain additional sequences from the population of cultured cells, we used a vector-tag concatenation technique providing 190 additional IS. Altogether, the profiles confirmed the bias for integration in transcription units. The vector did not congregate as hotspots and did not appear to target specific categories of genes. The diversity of the IS reflected the initial marking of a polyclonal population of cells. However, relatively few vector IS were found in vivo because only 30,40 unique IS were identified in each mouse using this approach. Although four to ten IS were shared by the blood and bone marrow, no common IS was found between mice or between any mouse and the cultured cells. Conclusions Taken as a whole, the pattern of genomic insertion of the WAS lentiviral vector was diverse and similar to that previously described for other HIV-1-derived lentiviral vectors. Testing cells destined for transplantation is unlikely to predict specific IS to be selected in vivo. Copyright © 2009 John Wiley & Sons, Ltd. [source] Using ColE1-derived RNA I for suppression of a bacterially encoded gene: implication for a novel plasmid addiction systemBIOTECHNOLOGY JOURNAL, Issue 6 2006Irene Pfaffenzeller Abstract The use of plasmid DNA for gene therapeutical purposes is a novel technology with advantages and drawbacks. One of the required improvements is to avoid antibiotic resistance genes or other additional sequences for selection within the plasmid. Here, we describe an alternative approach to equip a ColE1 plasmid with a regulatory function within the cell, which could be used for selection of plasmid carrying cells. No additional sequences are required, since the mechanism is based on RNA/RNA antisense interaction involving the naturally occurring RNA I derived from the plasmid's origin of replication. The plasmid replicational regulatory network was linked to the transcriptional regulatory network of an engineered target gene, present on the bacterial chromosome. Thus, gene suppression of a reporter could be achieved by mere presence of the ColE1-type plasmid pBR322. Proof of this concept was shown in shaker-flask experiments and fed-batch fermentation processes. The strategy of regulating gene expression by plasmid replication implicates a novel strategy for plasmid selection, as the gene to be suppressed could be toxic or growth hampering, providing advantage to plasmid carrying host cells. [source] | |||||||||||||