Comparison of the polytene chromosomes of the salivary gland, the fat body and the midgut nuclei of Drosophila auraria

Genetica ◽  
1990 ◽  
Vol 81 (2) ◽  
Author(s):  
P. Mavragani-Tsipidou ◽  
Z.G. Scouras ◽  
C.D. Kastritsis
Keyword(s):  
Salivary Gland ◽  
Fat Body ◽  
Polytene Chromosomes

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.

Genetic Analysis of the Drosophila 63F Early Puff: Characterization of Mutations in E63-1 and maggie, a Putative Tom22

Genetics ◽  
2000 ◽  
Vol 156 (1) ◽  
pp. 229-244
Author(s):  
Martina Vaskova ◽  
A M Bentley ◽  
Samantha Marshall ◽  
Pamela Reid ◽  
Carl S Thummel ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Genetic Analysis ◽  
Polytene Chromosomes ◽  
Reading Frame ◽  
Protein Levels ◽  
Ef Hand ◽  
Larval Salivary Gland ◽  
Complementation Groups ◽  
Inducible Genes ◽  
Early Puff

Abstract The 63F early puff in the larval salivary gland polytene chromosomes contains the divergently transcribed E63-1 and E63-2 ecdysone-inducible genes. E63-1 encodes a member of the EF-hand family of Ca2+-binding proteins, while E63-2 has no apparent open reading frame. To understand the functions of the E63 genes, we have determined the temporal and spatial patterns of E63-1 protein expression, as well as undertaken a genetic analysis of the 63F puff. We show that E63-1 is expressed in many embryonic and larval tissues, but the third-instar larval salivary gland is the only tissue where increases in protein levels correlate with increases in ecdysone titer. Furthermore, the subcellular distribution of E63-1 protein changes dynamically in the salivary glands at the onset of metamorphosis. E63-1 and E63-2 null mutations, however, have no effect on development or fertility. We have characterized 40 kb of the 63F region, defined as the interval between Ubi-p and E63-2, and have identified three lethal complementation groups that correspond to the dSc-2, ida, and mge genes. We show that mge mutations lead to first-instar larval lethality and that Mge protein is similar to the Tom22 mitochondrial import proteins of fungi, suggesting that it has a role in mitochondrial function.

A modification of Heidenhain's iron-haematoxylin technique, as used to stain smears of Drosophila larval polytene chromosomes and neuroblast cells

1971 ◽  
Vol 49 (1) ◽  
pp. 132-133 ◽  
Author(s):  
Albert E. Moorman
Keyword(s):  
Acetic Acid ◽  
Salivary Gland ◽  
Methyl Alcohol ◽  
Polytene Chromosomes ◽  
Larval Salivary Gland

Acetic-acid-fixed smears of Drosophila larval salivary gland chromosomes and of neuroblast cells from the larval ganglion undergoing mitosis are prepared by a modification of Heidenhain's iron-haematoxylin technique, in which absolute methyl alcohol is the solvent of all reagents used in the staining process.

Polytene and mitotic chromosome analysis in Ceratitis capitata (Diptera; Tephritidae)

1986 ◽  
Vol 28 (2) ◽  
pp. 180-188 ◽  
Author(s):  
D. G. Bedo
Keyword(s):  
X Chromosome ◽  
Silver Staining ◽  
Mitotic Chromosome ◽  
Ceratitis Capitata ◽  
Fat Body ◽  
Polytene Chromosomes ◽  
Chromosome Analysis ◽  
Mitotic Chromosomes ◽  
Chromosome Separation ◽  
Ectopic Pairing

Polytene chromosomes were found in several larval and pupal tissues of the Medfly, Ceratitis capitata, during a search for chromosomes suitable for detailed cytological analysis. Well-banded highly polytene chromosomes, which could be adequately separated and spread, were found in trichogen cells of the spatulate superior orbital bristles of male pupae. These chromosomes proved suitable for full polytene analysis. Thoracic trichogen cells of both male and female pupae also contain useful polytene chromosomes, although they are considerably thinner and thus more difficult to analyze. Contrasting with those in pupal trichogen cells, the chromosomes in the salivary glands, Malphighian tubules, midgut, hindgut, and fat body of larvae and pupae were difficult to prepare because of high levels of ectopic pairing and chromosome fragmentation. In hindgut preparations partial separation of up to three chromosomes was achieved, but in all other tissues no useful chromosome separation was possible. In trichogen polytene cells, five banded chromosomes and a prominent heterochromatic network associated with a nucleolus are found. The mitotic chromosomes respond to C- and Q-banding and silver staining with considerable variation. This is especially so in the X chromosome, which displays an extensive array of bands following both Q-banding and silver staining. Comparison of Q-banded metaphase and polytene chromosomes demonstrates that the five autosomes are represented by conventional polytene chromosomes, while the sex chromosomes are contained in the heterochromatic net, most of which fluoresces strongly. This suggests that the Q-bands of the mitotic X chromosome are replicated to a greater extent than the nonfluorescent material in polytene cells. This investigation shows C. capitata to have excellent cytological material for both polytene and mitotic analysis.Key words: Ceratitis capitata, Medfly, chromosomes (polytene), banding (chromosome).

Genetic and cytogenetic analysis of the fruit fly Rhagoletis cerasi (Diptera: Tephritidae)

Genome ◽  
2008 ◽  
Vol 51 (7) ◽  
pp. 479-491 ◽  
Author(s):  
Ilias Kounatidis ◽  
Nikolaos Papadopoulos ◽  
Kostas Bourtzis ◽  
Penelope Mavragani-Tsipidou
Keyword(s):  
Salivary Gland ◽  
Sex Chromosomes ◽  
Cytogenetic Analysis ◽  
Polytene Chromosomes ◽  
Fruit Fly ◽  
Pest Species ◽  
Heteromorphic Sex Chromosomes ◽  
Weak Points ◽  
Heterogametic Sex ◽  
Rhagoletis Cerasi

The European cherry fruit fly, Rhagoletis cerasi , is a major agricultural pest for which biological, genetic, and cytogenetic information is limited. We report here a cytogenetic analysis of 4 natural Greek populations of R. cerasi, all of them infected with the endosymbiotic bacterium Wolbachia pipientis . The mitotic karyotype and detailed photographic maps of the salivary gland polytene chromosomes of this pest species are presented here. The mitotic metaphase complement consists of 6 pairs of chromosomes, including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the salivary gland polytene complement has shown a total of 5 long chromosomes (10 polytene arms) that correspond to the 5 autosomes of the mitotic nuclei and a heterochromatic mass corresponding to the sex chromosomes. The most prominent landmarks of each polytene chromosome, the “weak points”, and the unusual asynapsis of homologous pairs of polytene chromosomes at certain regions of the polytene elements are also presented and discussed.

p75, a polypeptide component of karyoskeletal protein-enriched fractions associated with transcriptionally active loci of Drosophila melanogaster polytene chromosomes

1988 ◽  
Vol 8 (5) ◽  
pp. 1877-1886
Author(s):  
B M Benton ◽  
S Berrios ◽  
P A Fisher
Keyword(s):  
Tissue Culture ◽  
Drosophila Melanogaster ◽  
Transcriptional Regulation ◽  
Salivary Gland ◽  
Indirect Immunofluorescence ◽  
Polytene Chromosomes ◽  
Nuclear Interior ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Larval Salivary Gland

A 75-kilodalton polypeptide has been identified which copurifies with karyoskeletal protein-enriched fractions prepared from Drosophila melanogaster embryos. Results of indirect immunofluorescence experiments suggest that this protein, here designated p75, is primarily associated with puffed regions of larval salivary gland polytene chromosomes. In nonpolytenized Schneider 2 tissue culture cells, p75 appeared to be localized throughout the nuclear interior during interphase. In mitotic cells, p75 was redistributed diffusely. A possible role for karyoskeletal elements in transcriptional regulation is discussed.

scholarly journals H3K9 Promotes Under-Replication of Pericentromeric Heterochromatin in Drosophila Salivary Gland Polytene Chromosomes

Genes ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 93 ◽  
Author(s):  
Robin Armstrong ◽  
Taylor Penke ◽  
Samuel Chao ◽  
Gabrielle Gentile ◽  
Brian Strahl ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Dna Replication ◽  
Polytene Chromosomes ◽  
Cell Types ◽  
Gene Replacement ◽  
Pericentric Heterochromatin ◽  
Replication Initiation ◽  
H3k9 Methylation ◽  
Diploid Cells ◽  
And Function

Chromatin structure and its organization contributes to the proper regulation and timing of DNA replication. Yet, the precise mechanism by which chromatin contributes to DNA replication remains incompletely understood. This is particularly true for cell types that rely on polyploidization as a developmental strategy for growth and high biosynthetic capacity. During Drosophila larval development, cells of the salivary gland undergo endoreplication, repetitive rounds of DNA synthesis without intervening cell division, resulting in ploidy values of ~1350C. S phase of these endocycles displays a reproducible pattern of early and late replicating regions of the genome resulting from the activity of the same replication initiation factors that are used in diploid cells. However, unlike diploid cells, the latest replicating regions of polyploid salivary gland genomes, composed primarily of pericentric heterochromatic enriched in H3K9 methylation, are not replicated each endocycle, resulting in under-replicated domains with reduced ploidy. Here, we employ a histone gene replacement strategy in Drosophila to demonstrate that mutation of a histone residue important for heterochromatin organization and function (H3K9) but not mutation of a histone residue important for euchromatin function (H4K16), disrupts proper endoreplication in Drosophila salivary gland polyploid genomes thereby leading to DNA copy gain in pericentric heterochromatin. These findings reveal that H3K9 is necessary for normal levels of under-replication of pericentric heterochromatin and suggest that under-replication at pericentric heterochromatin is mediated through H3K9 methylation.

XXIII.—Types of Development of Polytene Chromosomes

1942 ◽  
Vol 61 (3) ◽  
pp. 316-327 ◽  
Author(s):  
A. M. Mellad
Keyword(s):  
Salivary Gland ◽  
Polytene Chromosomes ◽  
Chemical Study ◽  
New Techniques ◽  
Physical And Chemical

Until a few years ago the small size of the chromosomes limited the methods which could be used for their physical and chemical study. The discovery in 1933 that the salivary gland nuclei of Diptera contained giant multiple or polytene chromosomes threw the field open to the application of a variety of new techniques.

The genome of the olive fruit fly Bactrocera oleae: localization of molecular markers by in situ hybridization to the salivary gland polytene chromosomes

Genome ◽  
1999 ◽  
Vol 42 (4) ◽  
pp. 744-751 ◽  
Author(s):  
Anna Zambetaki ◽  
Antigone Zacharopoulou ◽  
Zacharias G. Scouras ◽  
Penelope Mavragani-Tsipidou
Keyword(s):  
Salivary Gland ◽  
Molecular Markers ◽  
In Situ Hybridization ◽  
Polytene Chromosomes ◽  
Fruit Fly ◽  
Bactrocera Oleae ◽  
Olive Fruit Fly ◽  
Olive Fruit
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