scholarly journals A yeast artificial chromosome clone map of the Drosophila genome.

Genetics ◽  
1994 ◽  
Vol 136 (4) ◽  
pp. 1385-1399
Author(s):  
H Cai ◽  
P Kiefel ◽  
J Yee ◽  
I Duncan

Abstract We describe the mapping of 979 randomly selected large yeast artificial chromosome (YAC) clones of Drosophila DNA by in situ hybridization to polytene chromosomes. Eight hundred and fifty-five of the clones are euchromatic and have primary hybridization sites in the banded portions of the polytene chromosomes, whereas 124 are heterochromatic and label the chromocenter. The average euchromatic clone contains about 211 kb and, at its primary site, labels eight or nine contiguous polytene bands. Thus, the extent as well as chromosomal position of each clone has been determined. By direct band counts, we estimate our clones provide about 76% coverage of the euchromatin of the major autosomes, and 63% coverage of the X. When previously reported YAC mapping data are combined with ours, euchromatic coverage is extended to about 90% for the autosomes and 82% for the X. The distribution of gap sizes in our map and the coverage achieved are in good agreement with expectations based on the assumption of random coverage, indicating that euchromatic clones are essentially randomly distributed. However, certain gaps in coverage, including the entire fourth chromosome euchromatin, may be significant. Heterochromatic sequences are underrepresented among the YAC clones by two to three fold. This may result, at least in part, from underrepresentation of heterochromatic sequences in adult DNA (the source of most of the clones analyzed), or from clone instability.

1994 ◽  
Vol 297 (3) ◽  
pp. 441-445 ◽  
Author(s):  
D Hickman ◽  
A Risch ◽  
V Buckle ◽  
N K Spurr ◽  
S J Jeremiah ◽  
...  

Arylamine N-acetyltransferase is encoded at two loci, AAC-1 and AAC-2, on human chromosome 8. The products of the two loci are able to catalyse N-acetylation of arylamine carcinogens, such as benzidine and other xenobiotics. AAC-2 is polymorphic and individuals carrying the slow-acetylator phenotype are more susceptible to benzidine-induced bladder cancer. We have identified yeast artificial chromosome clones encoding AAC-1 and AAC-2 and have used the cloned DNAs as fluorescent probes for in situ hybridization. The hybridization patterns allow assignment of AAC-1 and AAC-2 to chromosome 8p21.3-23.1, a region in which deletions have been associated with bladder cancer [Knowles, Shaw and Proctor (1993) Oncogene 8, 1357-1364].


Genetics ◽  
1993 ◽  
Vol 134 (3) ◽  
pp. 837-845
Author(s):  
J P Carulli ◽  
D E Krane ◽  
D L Hartl ◽  
H Ochman

Abstract The rates and patterns of molecular evolution in many eukaryotic organisms have been shown to be influenced by the compartmentalization of their genomes into fractions of distinct base composition and mutational properties. We have examined the Drosophila genome to explore relationships between the nucleotide content of large chromosomal segments and the base composition and rate of evolution of genes within those segments. Direct determination of the G + C contents of yeast artificial chromosome clones containing inserts of Drosophila melanogaster DNA ranging from 140-340 kb revealed significant heterogeneity in base composition. The G + C content of the large segments studied ranged from 36.9% G + C for a clone containing the hunchback locus in polytene region 85, to 50.9% G + C for a clone that includes the rosy region in polytene region 87. Unlike other organisms, however, there was no significant correlation between the base composition of large chromosomal regions and the base composition at fourfold degenerate nucleotide sites of genes encompassed within those regions. Despite the situation seen in mammals, there was also no significant association between base composition and rate of nucleotide substitution. These results suggest that nucleotide sequence evolution in Drosophila differs from that of many vertebrates and does not reflect distinct mutational biases, as a function of base composition, in different genomic regions. Significant negative correlations between codon-usage bias and rates of synonymous site divergence, however, provide strong support for an argument that selection among alternative codons may be a major contributor to variability in evolutionary rates within Drosophila genomes.


Blood ◽  
1995 ◽  
Vol 85 (8) ◽  
pp. 2132-2138 ◽  
Author(s):  
ML Veronese ◽  
M Ohta ◽  
J Finan ◽  
PC Nowell ◽  
CM Croce

Translocations involving chromosome 8 at band q24 and one of the Ig loci on chromosomes 14q32, 22q11, and 2p11 are the hallmark of Burkitt's lymphoma (BL). It has been previously observed that the exact localization of the breakpoints at chromosome 8q24 can vary significantly from patient to patient, scattering over a distance of more than 300 kb upstream of c-myc and about 300 kb downstream of c-myc. To generate probes for fluorescence in situ hybridization (FISH) that detect most c-myc translocations, we screened a yeast artificial chromosome (YAC) library from normal human lymphocytes by colony hybridization, using three markers surrounding the c-myc gene as probes. We obtained 10 YAC clones ranging in size between 500 and 200 kb. Two nonchimeric clones were used for FISH on several BL cell lines and patient samples with different breakpoints at 8q24. Our results show that the YAC clones detected translocations scattered along approximately 200 kb in both metaphase chromosomes and interphase nuclei. The sensitivity, rapidity, and feasibility in nondividing cells render FISH an important diagnostic tool. Furthermore, the use of large DNA fragments such as YACs greatly simplifies the detection of translocations with widely scattered breakpoints such as these seen in BL.


2003 ◽  
Vol 51 (4) ◽  
pp. 549-551 ◽  
Author(s):  
Anja Weise ◽  
Peter Harbarth ◽  
Uwe Claussen ◽  
Thomas Liehr

Fluorescence in situ hybridization (FISH) on human chromosomes in meta-and interphase is a well-established technique in clinical and tumor cytogenetics and for studies of evolution and interphase architecture. Many different protocols for labeling the DNA probes used for FISH have been published. Here we describe for the first time the successful use of Photoprobe biotin-labeled DNA probes in FISH experiments. Yeast artificial chromosome (YAC) and whole chromosome painting (wcp) probes were tested.


2019 ◽  
Vol 23 (2) ◽  
pp. 148-153
Author(s):  
D. S. Sidorenko ◽  
T. Yu. Zykova ◽  
V. A. Khoroshko ◽  
G. V. Pokholkova ◽  
S. A. Demakov ◽  
...  

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.


Blood ◽  
1996 ◽  
Vol 87 (9) ◽  
pp. 3579-3586 ◽  
Author(s):  
EJ Johnson ◽  
SW Scherer ◽  
L Osborne ◽  
LC Tsui ◽  
D Oscier ◽  
...  

Chromosome 7 translocations, deletions, or monosomy are associated with myelodysplasia (MDS) and acute myeloid leukemia both in children and adults. These chromosomal anomalies represent one of the most common cytogenetic abnormalities associated with these diseases and usually herald a poor prognosis. In this study two cosmid DNA probes that mapped to 7q22.1 and were known to be separated by approximately 500 kb were identified to flank the proximal inversion breakpoint in a patient carrying a constitutional inversion (7q22.1–34) associated with MDS. A yeast artificial chromosome (YAC) clone that encompassed the two cosmids was identified and shown to span the breakpoint. Fluorescence in situ hybridization was then used to analyze six additional patients with myelodysplasia and chromosomal rearrangements of the 7q22 region (three patients had translocations and three carried deletions). The breakpoint in one of the patients was found to be contained within the same YAC clone that spanned the inversion breakpoint. Moreover, this same interval was determined to be absent in all three patients with chromosomal deletions. These results suggest that this segment of DNA on chromosome 7q22.1 may contain specific gene(s) that have a significant role in myeloid malignancies.


1996 ◽  
Vol 98 (3) ◽  
pp. 321-322 ◽  
Author(s):  
Ingrid Stec ◽  
Ulrike Peters ◽  
Erik Harms ◽  
Michael R. Koehler ◽  
M. Schmid ◽  
...  

Genetics ◽  
1997 ◽  
Vol 145 (2) ◽  
pp. 281-295
Author(s):  
José María ◽  
Carmen Segarra ◽  
Alfredo Ruiz

Thirty-three DNA clones containing protein-coding genes have been used for in situ hybridization to the polytene chromosomes of two Drosophila repleta group species, D. repleta and D. buzzatii. Twenty-six clones gave positive results allowing the precise localization of 26 genes and the tentative identification of another nine. The results were fully consistent with the currently accepted chromosomal homologies and in no case was evidence for reciprocal translocations or pericentric inversions found. Most of the genes mapped to chromosomes 2 and 4 that are homologous, respectively, to chromosome arms 3R and 3L of D. melanogaster (Muller's elements E and D). The comparison of the molecular organization of these two elements between D. melanogaster and D. repleta (two species that belong to different subgenera and diverged some 62 million years ago) showed an extensive reorganization via paracentric inversions. Using a maximum likelihood procedure, we estimated that 130 paracentric inversions have become fixed in element E after the divergence of the two lineages. Therefore, the evolution rate for element E is approximately one inversion per million years. This value is comparable to previous estimates of the rate of evolution of chromosome X and yields an estimate of 4.5 inversions per million years for the whole Drosophila genome.


Blood ◽  
1992 ◽  
Vol 80 (7) ◽  
pp. 1659-1665
Author(s):  
L Kearney ◽  
M Bower ◽  
B Gibbons ◽  
S Das ◽  
T Chaplin ◽  
...  

The yeast artificial chromosome (YAC-13HH4), which spans a 440-kb region of DNA just distal to the CD3 locus on chromosome 11 at band q23, has been used to characterize a range of chromosomal translocations in acute leukemias from both adults and infants. In situ hybridization was performed on metaphase cells from bone marrow of 17 leukemias and two cell lines with a variety of chromosome 11q23 abnormalities. It was established that in infant leukemias the translocations t(11;19), t(4;11), and t(5;11) had occurred in the region defined by YAC 13HH4. Additionally, the translocations t(4;11), t(6;11), t(9;11), t(X;11), and t(10;11) in other leukemias were found to disrupt the same region of chromosome 11q23, although an exception was found in one t(6;11) translocation for which the breakpoint was distal to the YAC. One patient had a t(9;11) translocation in a therapy- related leukemia, suggesting that this class of etoposide-related malignancy has similar breakpoints to those occurring in de novo leukemias. An example of a lymphoma-derived translocation t(4;11) was shown to involve a deletion of the region defined by YAC 13HH4. A leukemia with a deletion on chromosome 11 (q23-q25) was also studied and it was shown that the YAC sequence was unaffected. It was concluded that, with a few exceptions, the translocations at 11q23 in a wide range of acute infant and adult leukemias occur in a common region and may result from a common underlying mechanism.


Sign in / Sign up

Export Citation Format

Share Document