Chromosomal Markers of Cancer

Abstract The hyperthermophilic archaeon Sulfolobus acidocaldarius exchanges and recombines chromosomal markers by a conjugational mechanism, and the overall yield of recombinants is greatly increased by previous exposure to UV light. This stimulation was studied in an effort to clarify its mechanism and that of marker exchange itself. A variety of experiments failed to identify a significant effect of UV irradiation on the frequency of cell pairing, indicating that subsequent steps are primarily affected, i.e., transfer of DNA between cells or homologous recombination. The UV-induced stimulation decayed rather quickly in parental cells during preincubation at 75°, and the rate of decay depended on the incubation temperature. Preincubation at 75° decreased the yield of recombinants neither from unirradiated parental cells nor from parental suspensions subsequently irradiated. We interpret these results as evidence that marker exchange is stimulated by recombinogenic DNA lesions formed as intermediates in the process of repairing UV photoproducts in the S. acidocaldarius chromosome.

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Use of a Small Palindrome Genetic Marker to Investigate Mechanisms of Double-Strand-Break Repair in Mammalian Cells

Genetics ◽

10.1093/genetics/154.3.1281 ◽

2000 ◽

Vol 154 (3) ◽

pp. 1281-1289 ◽

Cited By ~ 3

Author(s):

Julang Li ◽

Mark D Baker

Keyword(s):

Mismatch Repair ◽

Mammalian Cells ◽

Indirect Evidence ◽

Strand Break ◽

Double Strand Break ◽

Double Strand Break Repair ◽

Chromosomal Markers ◽

Vector Borne ◽

Break Repair ◽

The One

Abstract We examined mechanisms of mammalian homologous recombination using a gene targeting assay in which the vector-borne region of homology to the chromosome bore small palindrome insertions that frequently escape mismatch repair when encompassed within heteroduplex DNA (hDNA). Our assay permitted the product(s) of each independent recombination event to be recovered for molecular analysis. The results revealed the following: (i) vector-borne double-strand break (DSB) processing usually did not yield a large double-strand gap (DSG); (ii) in 43% of the recombinants, the results were consistent with crossover at or near the DSB; and (iii) in the remaining recombinants, hDNA was an intermediate. The sectored (mixed) genotypes observed in 38% of the recombinants provided direct evidence for involvement of hDNA, while indirect evidence was obtained from the patterns of mismatch repair (MMR). Individual hDNA tracts were either long or short and asymmetric or symmetric on the one side of the DSB examined. Clonal analysis of the sectored recombinants revealed how vector-borne and chromosomal markers were linked in each strand of individual hDNA intermediates. As expected, vector-borne and chromosomal markers usually resided on opposite strands. However, in one recombinant, they were linked on the same strand. The results are discussed with particular reference to the double-strand-break repair (DSBR) model of recombination.

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Chromosome mobilization of Legionella pneumophila with RK2::Mu and Tn5-Mob

Canadian Journal of Microbiology ◽

10.1139/m92-108 ◽

1992 ◽

Vol 38 (7) ◽

pp. 664-671 ◽

Cited By ~ 1

Author(s):

Clifford S. Mintz ◽

Chang Hua Zou

Keyword(s):

Genetic Mapping ◽

Key Words ◽

Legionella Pneumophila ◽

Transposon Tn5 ◽

Helper Plasmid ◽

Chromosome Transfer ◽

Chromosomal Markers

RK2::Mu plasmids and transposon Tn5-Mob were used to mobilize the Legionella pneumophila chromosome. Plate matings between L. pneumophila donors that contained RK2::Mu plasmids and auxotrophic recipients yielded recombinants at fequencies ranging from 10−6 to 10−7 per recipient for the markers tested. The presence of a Mu insertion in the chromosome of donors that harbored RK2::Mu plasmids increased the frequency of chromosome transfer of certain selected markers as compared with strains that contained RK2::Mu alone. Cotransfer experiments with Mu-containing donors and a thymidine and tryptophan auxotroph failed to reveal any linkage between the thy and trp loci in L. pneumophila. A strain that contained a chromosomal Tn5-Mob insertion and helper plasmid pRK24.4 transferred chromosomal markers at frequencies of 10−7 per recipient. These findings suggest that RK2::Mu plasmids and Tn5-Mob may be useful for genetic mapping experiments with L. pneumophila. Key words: Legionella pneumophila, chromosome transfer, Tn5-Mob, RK2::Mu.

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Cytogenetical analyses in three fish species of the genus Pimelodus(Siluriformes: Pimelodidae) from rio São Francisco: considerations about the karyotypical evolution in the genus

Neotropical Ichthyology ◽

10.1590/s1679-62252005000200006 ◽

2005 ◽

Vol 3 (2) ◽

pp. 285-290 ◽

Cited By ~ 25

Author(s):

Caroline Garcia ◽

Orlando Moreira Filho

Keyword(s):

Chromosome Pair ◽

Chromosomal Rearrangements ◽

Nucleolar Organizer ◽

Differential Staining ◽

Nucleolar Organizer Regions ◽

C Banding ◽

Heteromorphic Sex Chromosomes ◽

Chromosomal Markers ◽

Staining Techniques ◽

Species Specific

Karyotypes and other chromosomal markers were investigated in three species of the catfish genus Pimelodus, namely P. fur, P. maculatus and Pimelodus sp., from municipality of Três Marias, Minas Gerais, Brazil, using differential staining techniques (C-banding, Silver nitrate and CMA3 staining). The diploid chromosome number was 2n = 56 in P. maculatus and Pimelodus sp., while in P. fur 2n = 54. The karyotype of P. fur consisted in 32M + 8SM + 6ST + 8A with fundamental number (NF) of 100, that of P. maculatus 32M + 12SM + 12A with NF = 112, and that of Pimelodus sp. had 32M + 12Sm + 6ST + 6A with NF = 106.The nucleolar organizer regions (NORs) in all three species were invariably detected in telomeres of longer arm of the 20th chromosome pair. These sites were also positive after CMA3 and C-banding. No heteromorphic sex chromosomes were detected and C-banding pattern was species specific. Inferences about the karyotype differentiation in Pimelodus and putative chromosomal rearrangements are hypohesized.

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Analysis of 12 X-chromosomal markers in the population of central Croatia

Legal Medicine ◽

10.1016/j.legalmed.2016.07.001 ◽

2016 ◽

Vol 21 ◽

pp. 77-84 ◽

Cited By ~ 7

Author(s):

Josip Crnjac ◽

Petar Ozretić ◽

Siniša Merkaš ◽

Martina Ratko ◽

Mateja Lozančić ◽

...

Keyword(s):

Chromosomal Markers

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Episome-Carried Surface Antigen K88 of Escherichia coli I. Transmission of the Determinant of the K88 Antigen and Influence on the Transfer of Chromosomal Markers

Journal of Bacteriology ◽

10.1128/jb.91.1.69-75.1966 ◽

1966 ◽

Vol 91 (1) ◽

pp. 69-75 ◽

Cited By ~ 72

Author(s):

Ida Ørskov ◽

Frits Ørskov

Keyword(s):

Escherichia Coli ◽

Surface Antigen ◽

Chromosomal Markers

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Genetic Structure of Brazilian Populations of Triatoma sordida (Stål, 1859) (Hemiptera, Triatominae) by Means of Chromosomal Markers

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.18-0336 ◽

2019 ◽

Vol 100 (4) ◽

pp. 907-910 ◽

Cited By ~ 4

Author(s):

Fernanda Fernandez Madeira ◽

Yago Visinho dos Reis ◽

Isadora de Freitas Bittinelli ◽

Luiza Maria Grzyb Delgado ◽

Jader de Oliveira ◽

...

Keyword(s):

Genetic Structure ◽

Triatoma Sordida ◽

Chromosomal Markers ◽

Brazilian Populations

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Regeneration and pattern formation in planarians. II. and role of cell movements in blastema formation

Development ◽

10.1242/dev.107.1.69 ◽

1989 ◽

Vol 107 (1) ◽

pp. 69-76 ◽

Cited By ~ 1

Author(s):

E. Salo ◽

J. Baguna

Keyword(s):

Pattern Formation ◽

Cell Movement ◽

Formation Mechanisms ◽

Blastema Formation ◽

Chromosomal Markers ◽

Undifferentiated Cells ◽

Local Cell ◽

Number Of Cells ◽

Wound Epithelium

In planarians, blastema cells do not divide, and growth blastema is thought to result from the steady wound epithelium, of undifferentiated cells produced in the stump. However, whether these cells come only sources or whether cells placed far from the wound can participate, after long-range migrations, in the still uncertain. To study this problem, we have parameters of the process of regeneration: cell growth; number of cells produced by mitosis in the wound (postblastema); and rates of movement undifferentiated cells using grafting procedures with chromosomal markers. The results show that: (1) cells area spread (move) at higher rates than cells placed (90–140_mday-1 versus 40–50_mday-1); (2) cells than 500_m from the wound boundary are hardly 5-day-old blastemata; and (3) the number of cells within a 200–300_m postblastema area around the wound explain, provided their rates of movement are taken increasing number of blastema cells. From this, it is blastema cells in planarians originate from local mitotic activity jointly with local cell movement postblastema area around the wound match the blastema cells during regeneration. The implications for blastema growth and pattern formation mechanisms

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The order of replication of chromosomal markers inPseudomonas aeruginosastrain 1: I. Marker frequency analysis by transduction

Genetics Research ◽

10.1017/s0016672300014762 ◽

1974 ◽

Vol 23 (2) ◽

pp. 145-153 ◽

Cited By ~ 5

Author(s):

R. J. Booker ◽

J. S. Loutit

Keyword(s):

Pseudomonas Aeruginosa ◽

Frequency Analysis ◽

Relative Position ◽

Circular Chromosome ◽

Chromosome Map ◽

Chromosomal Markers ◽

Marker Frequency ◽

Slow Growing

SUMMARYThe generalized transducing phage F116 has been used to prepare lysates from fast- and slow-growing cultures ofPseudomonas aeruginosastrain 1. These lysates have been used to transduce a number of auxotrophic markers to prototrophy and the ratios of the numbers of transductants obtained with each lysate have been determined. Since the markers are those which have been mapped by conjugation in previous studies it has been possible to compare the ratios obtained for each marker with the relative position of the marker on the chromosome map. If the assumption is made that there is only one circular chromosome inP. aeruginosastrain 1 it is possible to suggest a way in which two apparently unlinked segments might be joined together. It is also possible to suggest that the chromosome replicates sequentially in two directions from a fixed origin.

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