Sex chromosomes and karyotypes of the Alticidae (Coleoptera).
Explore the source record for details and available documents.
SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Using human probes of whole chromosomes, the homoeologies between human and Leontopithecus chrysomelas (Platyrrhini) karyotypes were established. Thirty-three conserved segments were observed between the two species. Intrachromosomal rearrangements between the two species were identified using hybridization of chromosome arm probes of human chromosomes 1 and 3. We also used chromosomal data to investigate phylogenetic relationships of Callitrichines. These data were encoded using Cebus capucinus , a species which kept fairly ancestral chromosomes, as reference. Two equi-parsimonious trees, including reversion or convergence events, were obtained. The monophyly of Callitrichines is confirmed. They share nine chromosomal rearrangements at least. The Cebuella-Callithrix group forms a clade sharing five rearrangements at least. According to the tree considered, the Tamarins, Leontopithecus and Saguinus share two chromosomal rearrangements restricted to these two taxa or none. Callimico accumulated seven chromosomal rearrangements unshared with other taxa, at least. To avoid convergence and reversion events, we propose the hypothesis of a network (or populational) evolution. Six chromosomal rearrangements would have occurred during the period of this network evolution. Finally, the karyotype of the last common ancestor to all Callitrichines has been reconstructed. It possessed 48 chromosomes.
The evolution of chromosomes in species in the family Bovidae includes fusion and fission of chromosome arms (giving different numbers of acrocentric and metacentric chromosomes with a relatively conserved total number of arms) and evolution in both DNA sequence and copy number of the pericentromeric alpha-satellite I repetitive DNA sequence. Here, a probe representing the sheep alpha-satellite I sequence was isolated and hybridized to genomic DNA digests and metaphase chromosomes from various Bovidae species. The probe was highly homologous to the centromeric sequence in all species in the tribe Caprini, including sheep (Ovis aries), goat (Capra hircus) and the aoudad or Barbary sheep (Amnotragus lervia), but showed no detectable hybridization to the alpha-satellite I sequence present in the tribe Bovini and at most very weak to species in the tribes Hippotragini, Alcelaphini or Aepycerotini. The sex chromosomes of sheep, goat and aoudad did not contain detectable alpha-satellite I sequence; in sheep, one of the three metacentric autosomal chromosomes does not carry the sequence, while in aoudad, it is essentially absent in three large autosomal pairs as well as the large metacentric chromosome pair. The satellite probes can be used as robust chromosome and karyotype markers of evolution among tribes and increase the resolution of the evolutionary tree at the base of the Artiodactyla.
The telomere binding proteins TRF1 and TRF2 maintain and protect chromosome ends and confer karyotypic stability. Chromosome evolution in the genus Muntiacus is characterized by numerous tandem (end-to-end) fusions. To study TRF1 and TRF2 telomere binding proteins in Muntiacus species, we isolated and characterized the TERF1 and -2 genes from Indian muntjac (Muntiacus muntjak vaginalis; 2n = 6 female) and from Chinese muntjac (Muntiacus reveesi; 2n = 46). Expression analysis revealed that both genes are ubiquitously expressed and sequence analysis identified several transcript variants of both TERF genes. Control experiments disclosed a novel testis-specific splice variant of TERF1 in human testes. Amino acid sequence comparisons demonstrate that Muntiacus TRF1 and in particular TRF2 are highly conserved between muntjac and human. In vivo TRF2-GFP and immuno-staining studies in muntjac cell lines revealed telomeric TRF2 localization, while deletion of the DNA binding domain abrogated this localization, suggesting muntjac TRF2 represents a functional telomere protein. Finally, expression analysis of a set of telomere-related genes revealed their presence in muntjac fibroblasts and testis tissue, which suggests the presence of a conserved telomere complex in muntjacs. However, a deviation from the common theme was noted for the TERT gene, encoding the catalytic subunit of telomerase; TERT expression could not be detected in Indian or Chinese muntjac cDNA or genomic DNA using a series of conserved primers, while TRAP assay revealed functional telomerase in Chinese muntjac testis tissues. This suggests muntjacs may harbor a diverged telomerase sequence.
Atypical cytogenetic abnormalities were detected in peripheral primitive neuroectodermal tumors (PPNET) of the extremity in two children. One had an osseous tumor with a balanced reciprocal translocation, t(5;9)(q22;q32), and had a complete response to therapy. The other had a non-osseous tumor with an interstitial deletion, del(18)(q12.2q21.2), was resistant to combination therapy, and at autopsy had evidence of possible clonal evolution with the karyotype 46,XX der(8)t(8;8)(p11.2;q13), inv(16)(p13.2q12),del(18)(q12.2q21.2). Neither tumor demonstrated the t(11;22)(q24;q12) typically found in Ewing's sarcoma and PPNET, suggesting heterogeneity of the cytogenetic aberrations seen in this rare childhood malignancy.
Chromosome segregation was studied in 14 intra- and 20 inter-specific hybrid clones generated by fusion of Mus musculus embryonic stem (ES) cells with fibroblasts or splenocytes of DD/c mice or Mus caroli. As a control for in vitro evolution of tetraploid karyotype we used a set of hybrid clones obtained by fusion of ES cells (D3) with ES cells (TgTP6.3). Identification of the parental chromosomes in the clones was performed by microsatellite analysis and in situ hybridization with labeled species-specific probes. Both analyses have revealed three types of clones: (i) stable tetraploid, observed only for ES x ES cell hybrids; (ii) bilateral loss of chromosomes of both ES and somatic partners; (iii) unilateral segregation of chromosomes of the somatic partner. Observed unilateral segregation was extensive in ES-splenocyte cell hybrids, but lower in ES-fibroblast hybrid clones. Developmental state of the somatic partner is presumably responsible for directional chromosome loss. Nonrandom segregation implies that initial differences in the parental homologous chromosomes were not immediately equalized implying at least transient persistence of the differentiated epigenotype.
The yeast genome is currently being sequenced by a Consortium of European laboratories, in collaboration with a wider international network of researchers. It is expected that within the next two years Saccharomyces cerevisiae will become the first eukaryotic organism to have been completely genetically mapped and sequenced. This article traces the sequencing enterprise from its beginnings, outlining the intentions, the organisation, and the achievements so far. The tasks which remain are discussed, emphasising the follow-on research into the evolution of primitive karyotypes, and, more particularly, into the nature of novel genes revealed during sequencing. The functional analysis of novel genes is attracting an ever wider community of yeast scientists, so that research which began with a decision to sequence a simple genome promises to remain a focus for international cooperation.
In routine analyses, abnormalities of chromosome No. 17 were found in the bone marrow cells of 28 patients with Ph1-positive and three patients with Ph1-negative chronic myeloid leukemia (CML), 4 patients with acute nonlymphocytic leukemia (ANLL), and 4 patients with preleukemia. With three exceptions, all patients were in the blastic (CML) or the terminal phase. In 28 patients, the aberrant chromosome No. 17 arose by clonal evolution from the karyotype found at diagnosis or before the terminal phase. The abnormalities encountered were an isochromosome for the long arm, i(17q), (26 cases), translocations involving No. 17 (12 cases), trisomy 17 (three cases), and ring 17 (one case). In 35 patients, there was an unbalanced structural aberration of at least one of the No. 17 chromosomes. In every case (35/35), detailed analysis of the structurally abnormal No. 17 revealed loss of the distal part of the short arm (or possibly most of the short arm). Gain of the long arm (or at least its proximal part) was also common, but not invariably present (26/35). It is suggested that loss of 17p is a highly nonrandom event related to blastic crisis in CML and the terminal phase in other myeloid leukemias.
Chromosome studies on bone marrow cells and unstimulated peripheral lymphocytes from a patient with chronic myelogenous leukemia revealed the presence in all cells of two apparent Philadelphia chromosomes: one resulting from the classical translocation with a chromosome #9, and the other arising from a translocation between chromosomes #22 and #7. There was no normal chromosome #22. Some of the cells also had an i(17q), indicative of blast crisis. Repeated chromosome studies at different times during the course of the disease revealed the evolution of additional karyotypic changes. All cells from later samples had an extra #8; some of these cells had a third Philadelphia chromosome, whereas, others had a second Y chromosome. Although a few normal cells were seen in PHA-stimulated lymphocyte cultures, indicating that the patient has a normal constitutional karyotype, most of the cells had a karyotype identical to that found in unstimulated cultures. This unusual karyotype, 46,XY,t(7;22)(p22;q11),t(9;22)(q34;q11), represents the first case in which two apparent Philadelphia chromosomes are present in the leukemic cells from a patient in the absence of a normal #22 chromosome.
We describe the blastic transformation of a case of chronic myelocytic leukemia in which, among other abnormalities, one extra Philadelphia and one extra 9q+ were observed. Molecular studies and analysis of the clonal evolution of the karyotype led to the interpretation of such an unusual finding as the result of nondisjunction, rather than of a double t(9;22) translocation.
A 33-year-old male presented with acute lymphoblastic leukemia (ALL) characterized by translocation (11;19)(q23;p13.3). He received an allogeneic bone marrow transplant from a matched unrelated donor. Two years later his disease relapsed with an isolated intracardiac mass, presenting as right heart failure. He had no evidence of concomitant relapse in the bone marrow. Tumor cytogenetics revealed clonal evolution with the karyotype 46,XY,t(3;16)(q23;p13),t(11;19)(q23;p13.3), the chromosome 16 breakpoint involving the band where the genes for multidrug resistance-associated protein and CREB binding protein are known to reside. To our knowledge, this is the first report of an isolated extramedullary relapse of ALL in the heart.
We studied the long-term outcome of 87 adults with acute leukemia (age 15-59 years at transplant, median 27; 44 myeloid, 42 lymphoblastic, one biphenotypic) who were alive in continuous remission 2 years after a marrow (n = 74) or blood stem cell (n = 13) autograft. Nine relapsed 25-50 months (median 38) after transplantation. Five relapses were straightforward with no karyotypic or morphologic evolution of the original disease. Four recurrences were unusual, with development of myelodysplasia (n = 3) or myeloproliferative disease (n = 1). Five patients died of relapsed disease and four are still alive. Two patients died of complications related to the transplant, and one of ischemic heart disease. Seventy-nine patients (91%) are alive in remission 24-149 months (median 67) after transplantation (75 in continuous remission and four after further therapy) with Karnofsky scores of 80-100% (median 100%). The 8-year probabilities of survival, toxic death, and relapse (from the 2-year mark) are 89%, 3% and 12%. Eleven (12%) survivors had creatinine levels of >110 micromol/l (one more than double), and 14 (16%) had bilirubin levels of >17 mmol/l (one more than double) at the last follow-up. None of the following factors was found to be predictive for survival, non-relapse death, or relapse from the 2-year mark in multivariate analysis: age, sex, type of leukemia, disease stage, diagnosis, conditioning, origin of cells, and nucleated cell dose. We conclude that adult patients with acute leukemia who are alive and well 2 years following an autograft have a high probability of being cured, and the incidence of long-term liver and kidney dysfunction measured by serum bilirubin and creatinine is low.
The pathologic features of acute promyelocytic leukemia (APL) with t(15;17)(q22;q21) are highly characteristic, which with few exceptions enable a firm diagnosis to be made on morphologic grounds. An APL patient in first relapse presented with large, bizarre circulating blasts and bone marrow necrosis 2 weeks after chemotherapy consolidation for an arsenic trioxide-induced remission. Although a morphologic diagnosis could not be reached, cytogenetic investigations showed a near-triploid clone with t(15;17), confirming APL in second relapse. This case showed that clonal evolution with additional karyotypic aberrations might alter the blast morphology and pathologic features in APL.
Macrophages, the central players of innate immunity, control invading microbes by encapsulating them inside the phagosome, a nutrient-poor, reactive oxidant species-rich organelle. Nevertheless, some microbes, including the opportunistic yeast pathogen Candida glabrata, noted for its karyotype diversity, rapid evolution of antifungal drug resistance, and lack of meiosis, can survive and even replicate inside macrophages. However, it is not fully understood how C. glabrata responds to macrophage engulfment, and it is unknown how this presumably DNA-damaging environment influences the pathogen's genome stability. In this study, we used comparative transcriptomics to identify amino acid starvation and DNA damage as conditions eliciting C. glabrata responses most similar to macrophage engulfment. Consistent with this, we found that C. glabrata intra-macrophage survival and replication require master regulator of amino acid biosynthesis GCN4 and functional DNA double-strand break repair. Furthermore, comet assays provided the first direct evidence for increased DNA breaks in intra-macrophage yeast, and pulse-field gel electrophoresis showed that chromosomal alterations occur frequently in macrophage-passaged C. glabrata. Interestingly, these alterations could not be resolved by long read DNA sequencing, suggesting that they involved highly complex repetitive regions. Finally, we identified several point mutations emerging during macrophage passaging and showed that among them, a frameshift in RME1 (repressor of meiosis in Saccharomyces cerevisiae), increased C. glabrata intra-macrophage fitness. Together, these analyses point to amino acid deprivation, reveal elevated DNA breakage and chromosome instability, and raise intriguing questions about the role of meiotic gene orthologs in C. glabrata persisting and replicating within macrophages.
Genome mapping by means of radiation-induced interspecific cell hybrids is a direct way to localize both high- and low-polymorphic nucleotide sequences, including gene sequences, on animal chromosomes. Using radiation hybrid panels either individual chromosomes and loci or entire genome can be mapped. This efficient approach makes it possible to reach high resolution of markers (up to 100 bp) as well as unify the mapping language. Due to electronic means of communication, the same experimental material can be used in numerous laboratories to provide high-resolution extended genomic maps saturated with markers. Radiation hybrid mapping is a powerful tool for analysis of complex genome structure. Using radiation hybrid maps permitted verification of regions of chromosome homeology in various species and detection of regions with conserved sequence and conserved gene order. Identification of these regions is extremely important for understanding evolution of species karyotypes and for making use of positional cloning to isolate genes responsible for commercial traits as well as genes involved in hereditary human diseases.
The dog genome organization was extensively studied in the last ten years. The most important achievements are the well-developed marker genome maps, including over 3200 marker loci, and a survey of the DNA genome sequence. This knowledge, along with the most advanced map of the human genome, turned out to be very useful in comparative genomic studies. On the one hand, it has promoted the development of marker genome maps of other species of the family Canidae (red fox, arctic fox, Chinese raccoon dog) as well as studies on the evolution of their karyotype. But the most important approach is the comparative analysis of human and canine hereditary diseases. At present, causative gene mutations are known for 30 canine hereditary diseases. A majority of them have human counterparts with similar clinical and molecular features. Studies on identification of genes having a major impact on some multifactorial diseases (hip dysplasia, epilepsy) and cancers (multifocal renal cystadenocarcinoma and nodular dermatofibrosis) are advanced. Very promising are the results of gene therapy for certain canine monogenic diseases (haemophilia, hereditary retinal dystrophy, mucopolysaccharidosis), which have human equivalents. The above-mentioned examples prove a very important model role of the dog in studies of human genetic diseases. On the other hand, the identification of gene mutations responsible for hereditary diseases has a substantial impact on breeding strategy in the dog.
Investigations of solid tumors have shown that a very specific characterization of aberrant tissues can best be performed using a combination of cytologic, cytogenetic and molecular-cytogenetic methods. Thus, cytological analyses may serve to examine various features of tumors cultivated in vitro, e.g. growth peculiarities, cell morphology, specific details of cell division and mitotic rates, and anomalies of the spindle apparatus. Besides, chromosomal diagnostics characterizing non-specific aberrations focuses on the pathological karyotype and its evolution and heterogeneity, as well as on the development of secondary chromosomal aberrations. In the field of molecular-cytogenetic diagnostics we emphasize particularly the combination of metaphase and interphase analyses and the investigation of specific structural aberrations by fluorescence in situ hybridization (FISH). In contrast to the method of comparative genomic hybridization (CGH), the spectrum of applications for both methods is discussed. The findings described in this paper were obtained primarily from the analysis of 68 tumors of the urogenital tract (20 kidney tumors, 33 bladder tumors, 15 testis tumors).
Various characteristics of transformation were studied in subclones isolated from a hybrid cell line obtained by fusion of two Chinese hamster sub-lines having the same origin but presenting different properties, particularly in respect to heterotransplantability. Different subclones were obtained by cloning on semisoft agar. Transplantability, plating efficiency, agglutinability by concanavalin A and actinomycin D resistance were studied in parallel with the evolution of the karyotype to try to find a correlation between these various parameters. A relationship seems to exist between a chromosome marker arising in the hybrid and the percentage of tumours. The second part of this work dealth with the study of intra and interspecies hybrids, one of the parents of which was a normal, fibroblastic cell and the other of which contained the polyoma virus genome. In the hybrid cell this viral genome was expressed at several levels. Firstly, in the formation of specific polyoma virus-induced antigens and secondaryly, in surface properties normally considered related to the expression of tumorigenicity. Nevertheless, tumour development was repressed. Though the presence of characteristic antigens seemed necessary for the expression of malignant transformation, presence alone was not sufficient to induce malignant transformation of the cell. The study of inter-species mouse/hamster hybrids showed that this situation is not general. For this we examined the properties of hybrid cells between, on the one hand, a mouse tumorigenic cell bearing polyoma virus genetic information and, on the other, non-tumorigenic mouse or hamster cell. In this case the complete hamster genome could bot repress malignancy whereas a few mouse chromosomes sufficed to code for the expression of virus-induced tumour antigens and various malignant properties. It may be hoped that these hybrids could be used to pin-point the chromosome localization of the genetic factors of malignancy and could be used in immunoprotection studies or immunotherapy research.