Chromosomal polymorphisms involving telomere fusion, centromeric inactivation and centromere shift in the ant Myrmecia (pilosula) n=1

  title={Chromosomal polymorphisms involving telomere fusion, centromeric inactivation and centromere shift in the ant Myrmecia (pilosula) n=1},
  author={Hirotami T. Imai and Robert W. Taylor},
Detailed karyological surveys of the ant Myrmecia pilosula species group, which is characterized by the lowest chromosome number in higher organisms (2n=2), were attempted. We revealed that this species has developed highly complicated chromosomal polymorphisms. Their chromosome numbers are in the range 2n=2, 3, and 4, and six polymorphic chromosomes are involved, i.e., two for chromosome 1 (denoted as SM1 and ST1), three for chromosome 2 (A2, A′2, and M2), and M(1+2) for the 2n=2 karyotype. We… 

The X1X2Y sex chromosome system in the fish Hoplias malabaricus. I. G-, C- and chromosome replication banding

On the basis of the observed banding patterns, the Y chromosome may represent a stable dicentric, with an inactive centromere interstitially located on its long arm in Hoplias malabaricus.

Multiplication of 28S rDNA and NOR activity in chromosome evolution among ants of the Myrmecia pilosula species complex

It is suggested that the rDNA in the ancestral stock of the M. pilosula complex was localized originally in a pericentromeric C- band, and multiplied by chance with time during saltatory increases in C-banding following episodes of centric fission.

The Role of Fusion in Ant Chromosome Evolution: Insights from Cytogenetic Analysis Using a Molecular Phylogenetic Approach in the Genus Mycetophylax

The results obtained show the importance of fusions in chromosome changes towards a chromosome number reduction in Formicidae and how a phylogenetic background can be used to reconstruct hypotheses about chromosomes evolution.

Chromosomal Mapping of Tandem Repeats Revealed Massive Chromosomal Rearrangements and Insights Into Senna tora Dysploidy

The unusual chromosomal distribution of tandem repeats in S. tora not only enabled easy identification of individual chromosomes but also revealed the massive chromosomal rearrangements that have likely played important roles in shaping its dysploid karyotype.

Chromosome identification and mapping in the grassZingeria biebersteiniana (2n=4) using fluorochromes

Results constitute the first steps in constructing a physical gene map for Z. biebersteiniana and may facilitate future studies of the organization and reorganization of grass genomes, including research into the spatial arrangement of the genome inZingeria nuclei and much wider comparisons of synteny and genome evolution in grasses.

Chromosome Dynamics Regulating Genomic Dispersion and Alteration of Nucleolus Organizer Regions (NORs)

It is proposed that there are limited and non-limited genomic dispersion systems that result from genomic affinity rules, inducing specific chromosomal configurations that are related to NORs.

FISH analysis of the telomere sequences of bulldog ants (Myrmecia: Formicidae)

Chromosomes from several species of ants from the genus Myrmecia were hybridized with deoxyoligomer probes of either (T2AG2)7, the putative insect telomere repeat sequence, or (T1AG3)3, the vertebrate telomeres repeat sequence to speculate on the origin of the new telomees as the chromosome numbers increased.

The First Cytogenetic Data on Strumigenys louisianae Roger, 1863 (Formicidae: Myrmicinae: Dacetini): The Lowest Chromosome Number in the Hymenoptera of the Neotropical Region

In the present study, the first cytogenetic data was obtained for the ant species Strumigenys louisianae, from a genus possessing no previous cytogenetic data for the Neotropical region. The

Genomic dispersion of 28S rDNA during karyotypic evolution in the ant genusMyrmecia (Formicidae)

The chromosomal localization of 28S rDNA was investigated in 16 species of the Australian ant genusMyrmecia, with 2n numbers ranging from 4 to 76, using the fluorescence in situ hybridization method



Karyotype evolution in Australian ants

The data provide little support for the ancestral chromosome number in ants having been high with subsequent reduction, but suggest that the ancestral number was either very low with subsequent increase or coincident with the present mode (“modal hypothesis”).

Karyotypes, C-banding, and chromosomal location of active nucleolar organizing regions in Tapinoma (Hymenoptera, Formicidae).

The analysis of NOR sites in these species proved the existence of primary activity NOR in one or two chromosomes, respectively, whereas the other chromosomes showed secondary activity NOR, expressed only in a minority of cells.

Theoretical bases for karyotype evolution. II. The fusion burst in man and mouse.

Two closely linked possibilities are suggested that the fusion burst in man and mouse can theoretically be placed in karyotype evolution as a transitional phase in the main stream of the fission-inversion cycle, and it may be accelerated by some unknown (mutagenic) factors other than ionizing radiation.

Quantitative Analysis of Directionality in Mammalian Karyotype Evolution

An extensive karyograph analysis of the known mammalian karyotypes shows thatthere is little correlation between karyotypic and morphological level under any of the three hypotheses, and that there is a strong tendency for linear patterns to emerge when families are plotted separately.

Myrmecia pilosula, an Ant with Only One Pair of Chromosomes

A new sibling species of the primitive Australian ant Myrmecia pilosula has a chromosome number of n = 1. C-banding techniques confirm that the two chromosomes of workers are homologous. Males are


The behaviour in laboratory bioassays of male codling moth, Cydia pomonella (L.), when presented with various mixtures of (E, E)-8, 10-dodecadienol and the 2 saturated alcohols, dodecanol and

Controlled silver-staining of nucleolus organizer regions with a protective colloidal developer: a 1-step method

A 1-step silver-staining technique, requiring only 2 min to perform, is described for the differential staining of nucleolus organizer regions. A protective colloidal developer is used to control the

Centric fission in man and other mammals.

Modes of spontaneous chromosomal mutation and karyotype evolution in ants with reference to the minimum interaction hypothesis.

Translocations and Robertsonian polymorphisms are confirmed to be non-randomly distributed among ants, consistent with the minimum interaction hypothesis of Imai et al. (1986), under which translocations are expected to occur most frequently in low-numbered karyotypes.

Centric fission in man and mammals

  • 1988