1,720,997 research outputs found
The Heterochromatin Protein 1 (HP1) prevents telomere fusions in Drosophila melanogaster.
No full textA subset of the elements of the 17.31 retrotransposon family are preferentially located in regions of the Y chromosome that are polytenized in larval salivary glands of Drosophila melanogaster
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Chromosomal distribution of Heterochromatin Protein1 (HP1) in Drosophila: a cytological map of euchromatin HP1 binding sites
No full textThe Heterochromatin Protein 1 (HP1) is a conserved protein which is best known for its strong association with the heterochromatin of Drosophila melanogaster. We previously demonstrated that another important property of HP1 is its localization to the telomeres of Drosophila, a feature that reflects its critical function as a telomere capping protein. Here we report our analysis of the euchromatic sites to which HP1 localizes. Using an anti-HP1 antibody, we compared immunostaining patterns on polytene chromosomes of the Ore-R wild type laboratory strain and four different natural populations. HP1 was found to accumulate at specific euchromatic sites, with a subset of the sites conserved among strains. These sites do not appear to be defined by an enrichment of known repetitive DNAs. Comparisons of HP1 patterns among several Drosophila species revealed that association with specific euchromatic regions, heterochromatin and telomeres is a conserved characteristic of HP1. Based on these results, we argue that HP1 serves a broader function than typically postulated. In addition to its role in heterochromatin assembly and telomere stability, we propose that HP1 plays an important role in regulating the expression of many different euchromatic regions
Distribuzione degli elementi Stellate e crystal nel gruppo melanogaster
No full textSi tratta di un poster presentato al Congresso III FISV (Federazione Italiana Scienze della Vita
Differential expression of the Drosophila BX-C in polytene chromosomes in cells of larval fat bodies: a cytological approach to identifying in vivo targets of the homeotic Ubx, Abd-A and Abd-B proteins.
No full textWe have analyzed the expression of homeotic Bithorax Complex proteins in the fat bodies of Drosophila larvae by staining with specific antibodies. We have found that these proteins are differentially expressed along the anteroposterior (AP) axis of the fat body, with patterns parallel to those previously characterized for the larval and adult epidermis. As fat body nuclei have polytene chromosomes, we were able to identify the BX-C locus and show that it assumes a strongly puffed conformation in cells actively expressing the genes of the BX-C. Immunostaining of these polytene chromosomes provided the resolution to cytologically map binding sites of the three proteins: Ubx, Abd-A and Abd-B. The results of this work provide a system with which to study the positioning of chromatin regulatory proteins in either a repressed and/or active BX-C at the cytological level. In addition, the results of this work provide a map of homeotic target loci and thus constitute the basis for a systematic identification of genes that are direct in vivo targets of the BX-C genes
Distribuzione degli elementi Ste-like e cry-like nel genere Drosophila
No full textSi tratta di un poster presentato al 5° Congresso FISV nel 200
Trapeziectomia e ligamentoplastica in sospensione nel trattamento della rizoartrosi. Risultati da 2 a 12 anni.
No full text- …
