scholarly journals Cytogenetic study of three closely related species of Hawaiian Drosophila

Genome ◽  
1987 ◽  
Vol 29 (1) ◽  
pp. 47-57 ◽  
Author(s):  
Jayne N. Ahearn ◽  
Visut Baimai
Keyword(s):  
Cytogenetic Study ◽  
Hybrid Sterility ◽  
Polytene Chromosomes ◽  
Low Frequency ◽  
Small Mass ◽  
Fourth Chromosome ◽  
Metaphase Chromosomes ◽  
Chromosome Inversion ◽  
Hawaiian Drosophila ◽  
Allopatric Species

Three allopatric species from the Hawaiian islands, Drosophila bostrycha (Molokai), D. affinidisjuncta (West Maui), and D. disjuncta (East Maui), are extremely similar in morphology but differ in metaphase chromosomes by the amount and distribution of heterochromatin. Their polytene chromosomes are virtually homosequential with only slight differences at the tip of the microchromosome. Each is polymorphic for one or more inversions, especially in chromsome 4. Salivary gland chromosomes of F1 larvae reared either from wild-caught females or wild-caught males mated to standard laboratory stocks were examined for gene arrangements. Drosophila bostrycha and D. affinidisjuncta share a polymorphism for inversion 4v, which is much more frequent in the latter than in the former. In D. disjuncta 4v has been found only joined in a haplotype with three other inversions (g2 h2 i2) at a low frequency at Kipahulu Valley. Drosophila disjuncta is unique in having another fourth chromosome inversion, 4k, which is highest in frequency at Waikamoi. A new inversion, 2s, was discovered at Uluini Stream. Interspecific hybridizations were carried out in small mass matings. Backcrosses and dissections demonstrated that all F1 females were fertile. All F1 males were sterile in either of two categories with reciprocal hybrids uniformly manifesting one or the other type. Attempts to model the sterility mechanism suggest that more than chromosomal sterility is involved. Our results are discussed in relation to other closely related clusters of species having heterochromatin-based karyotype variations. Key words: heterochromatin, hybrid sterility, inversion, polymorphism, species divergence.

Cytological differences and chromosomal rearrangements in four members of the Anopheles dirus complex (Diptera: Culicidae)

Genome ◽  
1988 ◽  
Vol 30 (3) ◽  
pp. 372-379 ◽  
Author(s):  
V. Baimai ◽  
A. Poopittayasataporn ◽  
U. Kijchalao
Keyword(s):  
X Chromosome ◽  
Chromosomal Rearrangements ◽  
Polytene Chromosomes ◽  
Natural Populations ◽  
Low Frequency ◽  
Anopheles Dirus ◽  
Chromosome Inversion ◽  
Banding Patterns ◽  
Complex Species ◽  
Band Size

A reference photomap of the larval salivary gland, polytene chromosomes of the Anopheles dims complex (species A) is presented. Samples of species A, B, C, and D from natural populations in Thailand were compared to this standard map using the larval progeny of wild-caught females. All species show differences in their chromosome banding patterns involving band size, number, and shape, particularly at the free ends of the X, 2R, and 2L. These differences provide useful diagnostic characters for separating members of the species complex. However, overall banding patterns are conservative in the group: species A, B, and C are virtually homosequential. Species D is highly polymorphic for a single paracentric inversion in each of the four autosomal arms and has a fixed inversion on the X chromosome. This same X chromosome inversion occurs at low frequency in species A.Key words: Anopheles dirus, larval polytene chromosome, inversion polymorphisms.

scholarly journals CHROMOSOMAL SEQUENCES AND INTERISLAND COLONIZATIONS IN HAWAIIAN DROSOPHILA

Genetics ◽  
1983 ◽  
Vol 103 (3) ◽  
pp. 465-482
Author(s):  
Hampton L Carson
Keyword(s):  
Polytene Chromosomes ◽  
Complex Species ◽  
Hawaiian Drosophila ◽  
On This Island ◽  
Break Points ◽  
Chromosomal Sequences ◽  
Founder Events ◽  
Paracentric Inversions ◽  
Single Set

ABSTRACT Of 103 picture-winged Drosophila species endemic to the high Hawaiian islands, all but three are endemic to single islands or island complexes. They are presumed to have evolved in situ on each island. The banding pattern sequences of the five major polytene chromosomes of these species have been mapped to a single set of Standard sequences. Sequential variation among these chromosomes is due to 213 paracentric inversions. An atlas of their break points is provided. Geographical, morphological and behavioral data may be used to supplement the cytological information in tracing ancestry. Starting at the newer end of the archipelago, the 26 species of the Island of Hawaii (less than 700,000 years old) are inferred to have been derived from 19 founders, 15 from the Maui complex, three from Oahu and one from Kauai. The existence of 40 Maui complex species is explicable as resulting from 12 founders, ten from Oahu and two from Kauai. The 29 Oahu species can be explained by 12 founder events, five from Kauai and seven from Maui complex (summary in Figure 5). Although the ancestry of two Kauai species can be traced to newer islands, the ten remaining ones on this island (age about 5.6 million years) are apparently ancient elements in the fauna, relating ultimately to Palearctic continental sources.

Vibration Characteristics of Metamaterial Beams With Periodic Local Resonances

2014 ◽  
Vol 136 (6) ◽  
Author(s):  
M. Nouh ◽  
O. Aldraihem ◽  
A. Baz
Keyword(s):  
Band Gap ◽  
Low Frequency ◽  
Element Model ◽  
Small Mass ◽  
Vibration Characteristics ◽  
Structural Vibrations ◽  
Low Frequencies ◽  
Theoretical Predictions ◽  
Gap Characteristics ◽  
Unique Band

Vibration characteristics of metamaterial beams manufactured of assemblies of periodic cells with built-in local resonances are presented. Each cell consists of a base structure provided with cavities filled by a viscoelastic membrane that supports a small mass to form a source of local resonance. This class of metamaterial structures exhibits unique band gap behavior extending to very low-frequency ranges. A finite element model (FEM) is developed to predict the modal, frequency response, and band gap characteristics of different configurations of the metamaterial beams. The model is exercised to demonstrate the band gap and mechanical filtering capabilities of this class of metamaterial beams. The predictions of the FEM are validated experimentally when the beams are subjected to excitations ranging between 10 and 5000 Hz. It is observed that there is excellent agreement between the theoretical predictions and the experimental results for plain beams, beams with cavities, and beams with cavities provided with local resonant sources. The obtained results emphasize the potential of the metamaterial beams for providing significant vibration attenuation and exhibiting band gaps extending to low frequencies. Such characteristics indicate that metamaterial beams are more effective in attenuating and filtering low-frequency structural vibrations than plain periodic beams of similar size and weight.

scholarly journals THERMAL DEPOLARIZATION OF FLUORESCENCE FROM POLYTENE CHROMOSOMES STAINED WITH ACRIDINE ORANGE

1967 ◽  
Vol 33 (3) ◽  
pp. 597-604 ◽  
Author(s):  
James W. MacInnes ◽  
Robert B. Uretz
Keyword(s):  
Acridine Orange ◽  
Rotational Diffusion ◽  
Polytene Chromosomes ◽  
Degree Of Polarization ◽  
Fourth Chromosome ◽  
Thermal Change ◽  
Low Concentrations ◽  
Thermal Denaturation Temperature ◽  
Dna Thermal Denaturation ◽  
Increasing Temperature

The degree of polarization of fluorescence from stretched Chironomus thummi polytene chromosomes, stained with low concentrations of acridine orange (AO), decreases with increasing temperature. The "half temperature" of this decrease (T½R) is lower than the expected DNA thermal denaturation temperature (Tm) by about 20°C. T½R is lowered as histone is removed from chromosomes. Balbiani ring regions of the fourth chromosome have T½R's much lower than other regions, and nearly as low as chromosomes which had been extensively pretreated with trypsin to remove histone and other proteins. Measurements of the thermal change in the rotational diffusion rate of AO in solution with DNA indicate that the temperature at which the DNA-AO bonding changes from a "rigid" to a "loose" mode varies with the GC percentage of the DNA, and in the same fashion as Tm, although 20°C lower.

THE EVOLUTIONARY HISTORY OF DROSOPHILA BUZZATII. XII. THE GENETIC BASIS OF STERILITY IN HYBRIDS BETWEEN D. BUZZATII AND ITS SIBLING D. SERIDO FROM ARGENTINA

Genetics ◽  
1986 ◽  
Vol 114 (3) ◽  
pp. 841-857
Author(s):  
Horacio Naveira ◽  
Antonio Fontdevila
Keyword(s):  
Evolutionary History ◽  
Genetic Basis ◽  
Hybrid Sterility ◽  
Polytene Chromosomes ◽  
Chromosome Segment ◽  
Minimum Size ◽  
Drosophila Buzzatii ◽  
History Of ◽  
Male Hybrid ◽  
Chromosome Segments

ABSTRACT The genetic basis of hybrid sterility has been investigated in backcross segmental hybrids between two sibling species, Drosophila buzzatii and D. serido. Asynapsis of homologous bands in hybrid polytene chromosomes has been used to identify the D. serido chromosome segments introgressed into the D. buzzatti genome. All the investigated chromosomes contain male sterility factors. For autosomes, sterility is produced when an introgressed D. serido chromosome segment, or combination of segments, reaches a minimum size. On the other hand, any introgressed X chromosome segment from D. serido, irrespective of its size, produces either male hybrid sterility or inviability.

scholarly journals Immunofluorescence localization of Z-DNA in chromosomes: quantitation by scanning microphotometry and computer-assisted image analysis.

1985 ◽  
Vol 101 (4) ◽  
pp. 1422-1433 ◽  
Author(s):  
D J Arndt-Jovin ◽  
M Robert-Nicoud ◽  
P Baurschmidt ◽  
T M Jovin
Keyword(s):  
Image Analysis ◽  
Dna Sequences ◽  
Polytene Chromosomes ◽  
Computer Assisted ◽  
Distribution Profile ◽  
Metaphase Chromosomes ◽  
Dna Distribution ◽  
Class 1 ◽  
Computer Assisted Image ◽  
Z Dna

Anti-Z-DNA polyclonal and monoclonal immunoglobulins raised against left-handed polynucleotides show various degrees of specificity for base sequence and substitution. Class 1 IgGs recognize all Z-DNA with equal affinity; class 2 IgGs show a preference for d(G-C)n sequences and class 3 IgGs for d(G-C)n sequences with substitutions at the C5 position of the pyrimidine. These antibodies served as probes for the localization of Z-DNA in polytene and metaphase chromosomes and in interphase chromatin by indirect immunofluorescence. A quantitative assessment of the binding of anti-Z-DNA IgGs to polytene chromosomes of Chironomus and Drosophila was made by scanning microphotometry and by computer-assisted image analysis of double immunofluorescence and DNA-specific dye fluorescence images. The three classes of antibodies bind to most of the bands in acid fixed polytene chromosomes of C. thummi; however, preferential binding of one class of antibody over another can be observed in certain regions. These differences can be quantitated by arithmetic division or subtraction of the normalized digital images. If a class 2 antibody is first bound at saturating concentrations the binding of class 1 antibody is reduced throughout most bands by 40-50%. However, the telomeres of the three large chromosomes bind greater than 10 times as much class 1 antibody as class 2 antibody, indicating that the Z-DNA tracts in these regions are comprised largely of alternating sequences containing the A X T basepair, e.g., A-C. High-resolution image analysis of class 1 and class 2 immunofluorescence patterns and the total DNA distribution from polytene chromosomes of D. melanogaster show that the two antibody distributions are very similar in a large majority of the bands, but they often deviate from the mean DNA distribution profile. Z-DNA sequences of both G-C and A-C type are detectable at all levels of ploidy from 2n to 2(13)n and in species as diverse as insects and man. We conclude that the vast majority of polytene chromosome bands (genes) contain one or a few DNA sequences with potential for undergoing the B----Z transition and contain both alternating purine-pyrimidine G-C and A-C tracts or mixed sequences. Highly heterochromatic bands and telomeres have more Z potential sequences than do other bands.

scholarly journals Binding of anti-Z-DNA antibodies in quiescent and activated lymphocytes: relationship to cell cycle progression and chromatin changes.

1985 ◽  
Vol 5 (11) ◽  
pp. 3270-3273 ◽  
Author(s):  
L Staiano-Coico ◽  
B D Stollar ◽  
Z Darzynkiewicz ◽  
R Dutkowski ◽  
M E Weksler
Keyword(s):  
Cell Cycle ◽  
Human Peripheral Blood ◽  
Mammalian Species ◽  
Polytene Chromosomes ◽  
Peripheral Blood Lymphocytes ◽  
Cycle Phase ◽  
Metaphase Chromosomes ◽  
Dna Antibodies ◽  
Significant Change ◽  
Z Dna

Although regions of DNA reacting with anti-Z-DNA antibodies have been identified in the polytene chromosomes of Drosophila spp. and the metaphase chromosomes from a number of different mammalian species, the biological role of this DNA is unknown. Flow cytometry was used in the present studies to quantitate the binding of anti-Z-DNA antibodies in quiescent and activated human peripheral blood lymphocytes; the antibody binding was then correlated with cell cycle phase. The data show that quiescent (G0 or G1Q) lymphocytes are heterogeneous with respect to their reaction with anti-Z-DNA antibodies. The transition from quiescence (G1Q) into the cell cycle (G1), which involves decondensation of chromatin, did not result in any significant change in binding of these antibodies. In contrast, progression of cells from G1 through S and G2 is correlated with a 27% decrease in anti-Z-DNA antibody reactivity relative to total DNA content. No significant change was observed during the transition from G2 to mitosis (M).

scholarly journals Transformation of sperm nuclei to metaphase chromosomes in the cytoplasm of maturing oocytes of the mouse.

1986 ◽  
Vol 102 (3) ◽  
pp. 1039-1046 ◽  
Author(s):  
H J Clarke ◽  
Y Masui
Keyword(s):  
Morphological Changes ◽  
Small Mass ◽  
Sperm Nucleus ◽  
Metaphase Chromosomes ◽  
Oocyte Meiosis ◽  
Maturation In Vitro ◽  
Sperm Penetration ◽  
Sperm Nuclei ◽  
Metaphase I

Zona-free oocytes of the mouse were inseminated at prometaphase I or metaphase I of meiotic maturation in vitro, and the behavior of the sperm nuclei within the oocyte cytoplasm was examined. If the oocytes were penetrated by up to three sperm, maturation continued during subsequent incubation and became arrested at metaphase II. Meanwhile, each sperm nucleus underwent the following changes. First, the chromatin became slightly dispersed. By 6 h after insemination, this dispersed chromatin had become coalesced into a small mass, from which short chromosomal arms later became projected. Between 12 and 18 h after insemination, each mass of chromatin became resolved into 20 discrete metaphase chromosomes. In contrast, if oocytes were penetrated by four to six sperm, oocyte meiosis was arrested at metaphase I, and each sperm nucleus was transformed into a small mass of chromatin rather than into metaphase chromosomes. If oocytes were penetrated by more than six sperm, the maternal chromosomes became either decondensed or pycnotic, and the sperm nuclei were transformed into larger masses of chromatin. As control experiments, immature and fully mature metaphase II oocytes were inseminated. In the immature oocytes, which were kept immature by exposure to dibutyryl cyclic AMP, no morphological changes in the sperm nucleus were observed. On the other hand, in the fully mature oocytes, which were activated by sperm penetration, the sperm nucleus was transformed into the male pronucleus. Therefore, the cytoplasm of the maturing oocyte develops an activity that can transform the highly condensed chromatin of the sperm into metaphase chromosomes. However, the capacity of an oocyte is limited, such that it can transform a maximum of three sperm nuclei into metaphase chromosomes. Furthermore, the presence of more than six sperm causes a loss of the ability of the oocyte to maintain the maternal chromosomes in a metaphase state.

scholarly journals Polytene chromosomes reflect functional organization of the Drosophila genome

2019 ◽  
Vol 23 (2) ◽  
pp. 148-153
Author(s):  
D. S. Sidorenko ◽  
T. Yu. Zykova ◽  
V. A. Khoroshko ◽  
G. V. Pokholkova ◽  
S. A. Demakov ◽  
...  
Keyword(s):  
Banding Pattern ◽  
Functional Organization ◽  
Polytene Chromosomes ◽  
Diploid Cell ◽  
Regulatory Elements ◽  
Molecular Organization ◽  
Open Chromatin ◽  
Drosophila Genome ◽  
Fourth Chromosome ◽  
Molecular Map

Polytene chromosomes of Drosophila melanogaster are a convenient model for studying interphase chromosomes of eukaryotes. They are giant in size in comparison with diploid cell chromosomes and have a pattern of cross stripes resulting from the ordered chromatid arrangement. Each region of polytene chromosomes has a unique banding pattern. Using the model of four chromatin types that reveals domains of varying compaction degrees, we were able to correlate the physical and cytological maps of some polytene chromosome regions and to show the main properties of genetic and molecular organization of bands and interbands, that we describe in this review. On the molecular map of the genome, the interbands correspond to decompacted aquamarine chromatin and 5’ ends of ubiquitously active genes. Gray bands contain lazurite and malachite chromatin, intermediate in the level of compaction, and, mainly, coding parts of genes. Dense black transcriptionally inactive bands are enriched in ruby chromatin. Localization of several dozens of interbands on the genome molecular map allowed us to study in detail their architecture according to the data of whole genome projects. The distribution of proteins and regulatory elements of the genome in the promoter regions of genes localized in the interbands shows that these parts of interbands are probably responsible for the formation of open chromatin that is visualized in polytene chromosomes as interbands. Thus, the permanent genetic activity of interbands and gray bands and the inactivity of genes in black bands are the basis of the universal banding pattern in the chromosomes of all Drosophila tissues. The smallest fourth chromosome of Drosophila with an atypical protein composition of chromatin is a special case.  Using the model of four chromatin states and fluorescent in situ hybridization, its cytological map was refined and the genomic coordinates of all bands and interbands were determined. It was shown that, in spite of the peculiarities of this chromosome, its band organization in general corresponds to the rest of the genome. Extremely long genes of different Drosophila chromosomes do not fit the common scheme, since they can occupy a series of alternating bands and interbands (up to nine chromosomal structures) formed by parts of these genes.

scholarly journals An autosomal factor from Drosophila arizonae restores normal spermatogenesis in Drosophila mojavensis males carrying the D. arizonae Y chromosome.

Genetics ◽  
1993 ◽  
Vol 134 (1) ◽  
pp. 309-318
Author(s):  
A C Pantazidis ◽  
V K Galanopoulos ◽  
E Zouros
Keyword(s):  
Y Chromosome ◽  
Hybrid Sterility ◽  
Light And Electron Microscopy ◽  
Genetic Material ◽  
Drosophila Mojavensis ◽  
Fourth Chromosome ◽  
Motility Factor ◽  
Drosophila Arizonae ◽  
Male Hybrid ◽  
Necessary And Sufficient

Abstract Males of Drosophila mojavensis whose Y chromosome is replaced by the Y chromosome of the sibling species Drosophila arizonae are sterile. It is shown that genetic material from the fourth chromosome of D. arizonae is necessary and sufficient, in single dose, to restore fertility in these males. In introgression and mapping experiments this material segregates as a single Mendelian factor (sperm motility factor, SMF). Light and electron microscopy studies of spermatogenesis in D. mojavensis males whose Y chromosome is replaced by introgression with the Y chromosome of D. arizonae (these males are symbolized as mojYa) revealed postmeiotic abnormalities all of which are restored when the SMF of D. arizonae is co-introgressed (these males are symbolized as mojYaSMFa). The number of mature sperm per bundle in mojYaSMFa is slightly less than in pure D. mojavensis and is even smaller in males whose fertility is rescued by introgression of the entire fourth chromosome of D. arizonae. These observations establish an interspecific incompatibility between the Y chromosome and an autosomal factor (or more than one tightly linked factors) that can be useful for the study of the evolution of male hybrid sterility in Drosophila and the genetic control of spermatogenesis.

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