Search results for "chromosome"
showing 10 items of 1175 documents
Stress response in Drosophila subobscura. II. Puff activity during anoxia and recovery from anoxia.
1987
When individuals of Drosophila subobscura at 0 hr prepupa are submitted to anoxia (4 hr and 24 hr, respectively), their puffing pattern is very similar to that shown by individuals at the moment of development in which treatment began. The same expression of genes (the same puffing pattern and the same protein pattern) is induced in this species by recovery from anoxia as well as by heat shock treatment at 31 degrees C.
Puff activity after heat shock in two species of theDrosophila obscura group
1987
When individuals of Drosophila guanche are submitted to heat shock, five new puffs are induced. These puffs usually do not appear during normal development. Comparing these results with those obtained in Drosophila subobscura, also belonging to the obscura group, differences between the induced puffing pattern of both species have been found.
Transcriptional and translational study of the Drosophila subobscura hsp83 gene in normal and heat-shock conditions
1993
In this paper we report a transcriptional and translational study of the hsp83 gene of Drosophila subobscura. This gene is located at the 18C region of the J chromosome. A monoclonal antibody raised against hsp83 was used for the immunological detection of this protein by Western blotting throughout the development of D. subobscura in control and heat-shock conditions. Our results indicate that puff 18C is not only heat-shock inducible but is also expressed during normal development and its level of expression increases at the end of the prepupa period. We detected hsp83 at normal temperatures, in particular developmental stages with the exception of the larval and the beginning of prepupa…
Transcription of heat shock gene loci versus non-heat shock loci in Chironomus polytene chromosomes: evidence for heat-induced formation of novel put…
1995
The heat shock response of Chironomus polytene chromosomes was reexamined. The in vivo effects of heat shock on chromosomal [3H]uridine labeling, RNA polymerase II distribution and ribonucleoprotein (RNP) formation were investigated. One primary result is a clarification of the number and location of chromosomal sites strongly induced by treatment at 37 degrees C for 60 min. In total, seven major heat shock loci were identified by transcription autoradiography in Chironomus tentans: I-20A, II-16B, II-10C, II-4B, II-1C, III-12B, and IV-5C. Secondly, combining immunofluorescence with transcription autoradiography, I find RNA polymerase II occurring after heat shock at multiple chromosomal sit…
γδT cells elicited by CMV reactivation after allo-SCT cross-recognize CMV and leukemia.
2013
Human cytomegalovirus (CMV) infections and relapse of disease remain major problems after allogeneic stem cell transplantation (allo-SCT), in particular in combination with CMV-negative donors or cordblood transplantations. Recent data suggest a paradoxical association between CMV reactivation after allo-SCT and reduced leukemic relapse. Given the potential of Vδ2-negative γδT cells to recognize CMV-infected cells and tumor cells, the molecular biology of distinct γδT-cell subsets expanding during CMV reactivation after allo-SCT was investigated. Vδ2(neg) γδT-cell expansions after CMV reactivation were observed not only with conventional but also cordblood donors. Expanded γδT cells were ca…
Genetic rearrangement of the atzAB atrazine-degrading gene cassette from pADP1::Tn5 to the chromosome of Variovorax sp. MD1 and MD2
2007
International audience; We report the characterization of the rearrangement phenomena responsible for the movement of the atrazine-degrading atzA and B genes from pADP1::Tn5 to the chromosome of Variovorax sp. MD1 and MD2. Long PCRs and Southern blot analyses revealed that the two genes forming a gene cassette moved in a unique rearrangement event. It also revealed that the boundaries of the plasmid sequence inserted in the chromosome correspond to IS1071or to sequences close to IS1071. It suggests that this genetic rearrangement could result from the transposition of the composite transposon delimited by IS1071 insertion sequences and containing atzA and atzB genes. In addition, for MD1 an…
ISWI Regulates Higher-Order Chromatin Structure and Histone H1 Assembly In Vivo
2007
Imitation SWI (ISWI) and other ATP-dependent chromatin-remodeling factors play key roles in transcription and other processes by altering the structure and positioning of nucleosomes. Recent studies have also implicated ISWI in the regulation of higher-order chromatin structure, but its role in this process remains poorly understood. To clarify the role of ISWI in vivo, we examined defects in chromosome structure and gene expression resulting from the loss of Iswi function in Drosophila. Consistent with a broad role in transcriptional regulation, the expression of a large number of genes is altered in Iswi mutant larvae. The expression of a dominant-negative form of ISWI leads to dramatic a…
Inverted and mirror repeats in model nucleotide sequences.
2007
We analytically and numerically study the probabilistic properties of inverted and mirror repeats in model sequences of nucleic acids. We consider both perfect and non-perfect repeats, i.e. repeats with mismatches and gaps. The considered sequence models are independent identically distributed (i.i.d.) sequences, Markov processes and long range sequences. We show that the number of repeats in correlated sequences is significantly larger than in i.i.d. sequences and that this discrepancy increases exponentially with the repeat length for long range sequences.
Genome size and chromosomes in marine sponges [Suberites domuncula, Geodia cydonium]
1995
The genome size of the marine sponges Suberites domuncula and Geodia cydonium has been determined by flow cytofluorometric analysis using diamidino-phenylindole [DAPI]. Using human lymphocytes as reference the amount of DNA in cells from S. domuncula has been determined to be 3.7 pg and that of G. cydonium 3.3 pg. While no chromosomes could be identified in G. cydonium, the karyotype of the Suberites domuncula is 32 chromosomes in the diploid state. The size of the chromosomes was between 0.25 and 1.0 micron. No pronounced banding pattern was visible.
Hypercalciuria and kidney calcifications in terminal 4q deletion syndrome: further evidence for a putative gene on 4q.
2004
We report a newborn girl with a de novo terminal 4q deletion (q31.3 --> qter) and a characteristic phenotype of minor facial anomalies, cleft palate, congenital heart defect, abnormalities of hands and feet, and postnatal onset of growth deficiency. Laboratory studies showed excessive urinary calcium excretion on standard milk formula and on oral calcium load. Blood measurements of parathyroid hormone, calcitonin, bicarbonate, calcium, phosphorus, magnesium, sodium, chlorine, potassium, and urinary measurements of phosphorus, magnesium, sodium, chlorine, potassium were normal for age. At 2 months of life, ultrasonography showed kidney calcifications. Clinical and laboratory data support the…