The Afrotropical Drosophila montium subgroup: Balbiani ring 1, polytene chromosomes, and heat shock response of Drosophila vulcana

Genome ◽  
1996 ◽  
Vol 39 (3) ◽  
pp. 588-597 ◽  
Author(s):  
E. Pardali ◽  
E. Feggou ◽  
E. Drosopoulou ◽  
I. Konstantopoulou ◽  
Z. G. Scouras ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Heat Shock ◽  
Chromosomal Rearrangements ◽  
Polytene Chromosomes ◽  
Balbiani Ring ◽  
Shock Response ◽  
Small Hsps ◽  
Inducible Protein ◽  
Montium Subgroup ◽  
Tandem Duplications

A detailed photographic map of the salivary gland polytene chromosomes of Drosophila vulcana, an Afrotropical species of the montium subgroup of the melanogaster group, is presented, along with chromosomal rearrangements, such as reverse tandem duplications and inversions, the well-formed Balbiani ring 1, and the most prominent puffs during normal larval and white prepupal development and after ecdysone treatment. In addition, the heat inducible protein and puffing pattern and the loci of the major heat shock genes, namely, hsp70, hsp83, the "small" hsps, and a putative hsp68, of this species were studied. In the light of the data revealed by the above studies, phylogenetic relationships among the montium subgroup species are attempted. Key words : Drosophila, Balbiani ring, polytene chromosomes, heat shock, puffs, genes, proteins, hsp70 single locus.

Cytotaxonomic differentiation of the Afrotropical Drosophila montium subgroup: D. diplacantha and D. seguyi. The major role of reverse tandem duplications

Genome ◽  
1994 ◽  
Vol 37 (6) ◽  
pp. 935-944 ◽  
Author(s):  
P. Mavragani-Tsipidou ◽  
A. Zambetaki ◽  
K. Kleanthous ◽  
E. Pangou ◽  
Z. G. Scouras
Keyword(s):  
Polytene Chromosomes ◽  
Balbiani Ring ◽  
Developmental Profile ◽  
Intraspecific Polymorphism ◽  
Balbiani Rings ◽  
Chromosome Maps ◽  
Temporal And Spatial ◽  
Montium Subgroup ◽  
Tandem Duplications

Aiming to establish phylogenetic relationships among species of the montium subgroup, detailed polytene chromosome maps are given showing intraspecific polymorphism and ecdysone induced larval puffing pattern profiles of two Afrotropical members of this subgroup, Drosophila diplacantha and D. seguyi. Both species exhibit two unique characteristics that define the montium subgroup, namely, a large number of reverse tandem duplications and a progressive darkening of anterior spiracles of the late third instar larvae, which is accompanied by a definite temporal and spatial puffing pattern of the salivary gland chromosomes. In contrast with the well-formed Balbiani ring 1 (BR1) observed in Oriental and Indian montium species, BR1 exhibits a different developmental profile in D. diplacantha, while it is obscured in D. seguyi. Although phyletic comparisons of five species from five different complexes within the subgroup show some conservation in banding and puffing pattern homologies, an analysis to assign map sections by sequential rearrangements remains unresolved at this time. The evolution of the subgroup is discussed in relation with the sharing of reverse tandem duplications, especially those including the montium BRs.Key words: Drosophila montium, polytene chromosomes, Balbiani rings, puffs, duplications, inversions.

Evolutionary implications of duplications and Balbiani rings in Drosophila. A study of Drosophila serrata

Genome ◽  
1990 ◽  
Vol 33 (4) ◽  
pp. 478-485 ◽  
Author(s):  
P. Mavragani-Tsipidou ◽  
N. Kyrpides ◽  
Z. G. Scouras
Keyword(s):  
Salivary Gland ◽  
Larval Development ◽  
Chromosomal Rearrangements ◽  
Balbiani Ring ◽  
Intercalary Heterochromatin ◽  
Developmental Profile ◽  
Balbiani Rings ◽  
Drosophila Serrata ◽  
Tandem Duplications

Drosophila serrata, a species of subgroup montium, exhibits in its salivary-gland chromosomes a high number of inverted tandem duplications and a well-formed Balbiani ring. A photographic map, the duplications, and the Balbiani ring of this species are presented. Also presented are the most prominent puffs during normal larval development and after ecdysone treatment, as well as intercalary heterochromatin regions of the above chromosomes. These data are discussed and compared with those of Drosophila auraria, another species of subgroup montium. All the inverted tandem duplications found in both species are homozygous and are not accompanied by other types of chromosomal rearrangements. These results argue in favor of the relatively old origin of these structures. The similarity of the structure and the developmental profile of the Balbiani ring 1 in both species may indicate a necessary role served by the Balbiani ring 1 and hence its selection during evolution.Key words: Drosophila, duplications, Balbiani ring, ecdysone, intercalary heterochromatin.

Identification of novel heat shock-induced long non-coding RNA in human cells

2020 ◽  
Author(s):  
Rena Onoguchi-Mizutani ◽  
Yoshihiro Kishi ◽  
Yoko Ogura ◽  
Yuuki Nishimura ◽  
Naoto Imamachi ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Response ◽  
A549 Cells ◽  
Heat Shock Factor 1 ◽  
Protein Coding ◽  
Heat Shock Stress ◽  
Non Coding Rna ◽  
Shock Response ◽  
Inducible Protein ◽  
Inducible Genes

Abstract The heat-shock response is a crucial system for survival of organisms under heat stress. During heat-shock stress, gene expression is globally suppressed, but expression of some genes, such as chaperone genes, is selectively promoted. These selectively activated genes have critical roles in the heat-shock response, so it is necessary to discover heat-inducible genes to reveal the overall heat-shock response picture. The expression profiling of heat-inducible protein-coding genes has been well-studied, but that of non-coding genes remains unclear in mammalian systems. Here, we used RNA-seq analysis of heat shock-treated A549 cells to identify seven novel long non-coding RNAs that responded to heat shock. We focussed on CTD-2377D24.6 RNA, which is most significantly induced by heat shock, and found that the promoter region of CTD-2377D24.6 contains the binding site for transcription factor HSF1 (heat shock factor 1), which plays a central role in the heat-shock response. We confirmed that HSF1 knockdown cancelled the induction of CTD-2377D24.6 RNA upon heat shock. These results suggest that CTD-2377D24.6 RNA is a novel heat shock-inducible transcript that is transcribed by HSF1.

The Balbiani ring and the polytene chromosomes of Drosophila bicornuta

Genome ◽  
1992 ◽  
Vol 35 (1) ◽  
pp. 64-67 ◽  
Author(s):  
P. Mavragani-Tsipidou ◽  
Z. G. Scouras ◽  
A. Natsiou-Voziki
Keyword(s):  
Salivary Gland ◽  
Larval Development ◽  
Banding Pattern ◽  
Polytene Chromosomes ◽  
Balbiani Ring

A study of the BR1 and of the most prominent puffs during larval development and after in vitro ecdysterone treatment, as well as of the banding pattern and inverted tandem chromosomal duplications of the salivary gland chromosomes of Drosophila bicornuta, is presented in this report. These data are compared and discussed with those of D. auraria and D. serrata, two other montium species.Key words: Drosophila, Balbiani ring, duplications, ecdysterone.

Cytogenetic analysis of Malpighian tubule and salivary gland polytene chromosomes of Bactrocera oleae (Dacus oleae) (Diptera: Tephritidae)

Genome ◽  
1995 ◽  
Vol 38 (6) ◽  
pp. 1070-1081 ◽  
Author(s):  
Anna Zambetaki ◽  
Kleanthis Kleanthous ◽  
Penelope Mavragani-Tsipidou
Keyword(s):  
Salivary Gland ◽  
Banding Pattern ◽  
Fat Body ◽  
Polytene Chromosomes ◽  
Malpighian Tubule ◽  
Bactrocera Oleae ◽  
Dacus Oleae ◽  
Somatic Tissues ◽  
Ectopic Pairing ◽  
Tandem Duplications

Photomaps of the Malpighian tubule and the salivary gland polytene chromosomes of Bactrocera oleae (Dacus oleae) are presented and compared with those of the fat body. Five polytene chromosomes (10 polytene arms) corresponding to the five autosomes of the mitotic nuclei, as well as a heterochromatic mass corresponding to the sex chromosomes, are observed in the nuclei of the three somatic tissues. The most prominent features of each polytene chromosome, the reverse tandem duplications, as well as the rather unusual ectopic pairing of the telomeric regions of different chromosome arms, are described. The constancy of the banding pattern based on the analysis of the three larval tissues is discussed.Key words: Bactrocera oleae (Dacus oleae), polytene chromosomes, salivary gland, Malpighian tubule, banding pattern.

Heat-shock response in a tropical Chironomus: seasonal variation in response and the effect of developmental stage and tissue type on heat shock protein synthesis

Genome ◽  
1989 ◽  
Vol 32 (4) ◽  
pp. 676-686 ◽  
Author(s):  
B. B. Nath ◽  
S. C. Lakhotia
Keyword(s):  
Protein Synthesis ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Developmental Stage ◽  
Heat Shock Response ◽  
Polytene Chromosomes ◽  
Malpighian Tubules ◽  
Tissue Type ◽  
Developmental Study ◽  
Shock Response

Examination of heat shock induced transcriptional activity in salivary gland polytene nuclei of a tropical Chironomus, C. striatipennis, revealed nine heat-shock puffs. In 24 °C-reared larvae optimal heat-shock response was seen at 39 °C, while a 41 °C shock was nearly lethal. In a population grown under natural conditions of seasonal variations, the heat-shock response was dependent upon the current ambient temperature. In summer months, response to 39 °C was variable, from complete to no induction of heat-shock puffs in different cells. In control glands from larvae growing at 33–36 °C in summer, heat-shock genes were not active, although in 24 °C-reared larvae, 33 °C already caused partial induction. Unlike the 24 °C-reared population, a 41 °C shock to summer larvae was not lethal. [35S]Methionine-labelled protein synthesis pattern in the summer larvae revealed appreciable accumulation of heat-shock polypeptides in control glands, which possibly autoregulates their further induction and also explains the better thermotolerance of these larvae. In a developmental study of a 24 °C-reared population, some heat-shock polypeptides were found to be commonly synthesized at 39 °C in all the tissues (salivary glands of larvae; Malpighian tubules of larvae, pupae, and adult; adult ovaries), while other heat-shock polypeptides showed apparent tissue and (or) developmental stage specificity. Heat shock protein 70 was most abundantly synthesized in all the tissues examined.Key words: temperature shock, thermotolerance, heat-shock polypeptides, polytene chromosomes, puffs.

scholarly journals Cyanobacterial heat-shock response: role and regulation of molecular chaperones

Microbiology ◽  
2014 ◽  
Vol 160 (4) ◽  
pp. 647-658 ◽  
Author(s):  
Hema Rajaram ◽  
Akhilesh Kumar Chaurasia ◽  
Shree Kumar Apte
Keyword(s):  
Heat Shock ◽  
Molecular Chaperones ◽  
Heat Shock Response ◽  
Ecological Niches ◽  
Nitrogen Fixing ◽  
Shock Response ◽  
Genes Encoding ◽  
Small Hsps ◽  
Shock Proteins

Cyanobacteria constitute a morphologically diverse group of oxygenic photoautotrophic microbes which range from unicellular to multicellular, and non-nitrogen-fixing to nitrogen-fixing types. Sustained long-term exposure to changing environmental conditions, during their three billion years of evolution, has presumably led to their adaptation to diverse ecological niches. The ability to maintain protein conformational homeostasis (folding–misfolding–refolding or aggregation–degradation) by molecular chaperones holds the key to the stress adaptability of cyanobacteria. Although cyanobacteria possess several genes encoding DnaK and DnaJ family proteins, these are not the most abundant heat-shock proteins (Hsps), as is the case in other bacteria. Instead, the Hsp60 family of proteins, comprising two phylogenetically conserved proteins, and small Hsps are more abundant during heat stress. The contribution of the Hsp100 (ClpB) family of proteins and of small Hsps in the unicellular cyanobacteria (Synechocystis and Synechococcus) as well as that of Hsp60 proteins in the filamentous cyanobacteria (Anabaena) to thermotolerance has been elucidated. The regulation of chaperone genes by several cis-elements and trans-acting factors has also been well documented. Recent studies have demonstrated novel transcriptional and translational (mRNA secondary structure) regulatory mechanisms in unicellular cyanobacteria. This article provides an insight into the heat-shock response: its organization, and ecophysiological regulation and role of molecular chaperones, in unicellular and filamentous nitrogen-fixing cyanobacterial strains.

The 3-D substructure of RNA in nascent RNP granules: A novel application of osmium ammine-B staining and electron spectroscopic imaging

1992 ◽  
Vol 50 (1) ◽  
pp. 504-505
Author(s):  
Ada L. Olins ◽  
Donald E. Olins ◽  
Manesh B. Shah ◽  
Henri A. Levy ◽  
David P. Bazett-Jonest
Keyword(s):  
Salivary Gland ◽  
Polytene Chromosomes ◽  
Spectroscopic Imaging ◽  
Secretory Proteins ◽  
Chironomus Tentans ◽  
Balbiani Ring ◽  
Electron Spectroscopic Imaging ◽  
Nuclear Pores ◽  
Rnp Granules

RNA has a particulate substructure when visualized in situ with the nucleic acid specific stain osmium ammine-B (OA-B). In this study energy spectroscopic imaging (ESI) was used to enhance the contrast and collect the data for tomographic reconstructions.The Balbiani ring (BR) in the salivary gland polytene chromosomes of Chironomus tentans larvae furnishes a well known model for the structure of nascent m-RNA. This gland produces copious amounts of silk-like secretory proteins which are very large (106 daltons). The site of transcription, the BR, is easily recognized in the EM by its characteristic “puff” structure and electron-dense granular transcripts. Mature BR granules are 45-50 nm in diameter and can be easily observed within the nucleus and passing through nuclear pores.

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