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1.
Complex and simple sequences in human repeated DNAs   总被引:9,自引:0,他引:9  
Highly repeated human DNA sequences were isolated by isopycnic centrifugation, or were eluted from gels after restriction enzyme cleavage. High molecular weight DNA peaks separable from the bulk of the DNA in a variety of gradients were shown to consist of very simple sequences characteristic of simple satellite DNAs; DNA fingerprint studies indicated each of these peaks could consist of tandem repeats of a specific oligonucleotide sequence as low as 10 base pairs (bp) long. All the gradient peaks could be assigned to one of two sequence groups and several different buoyant density peaks revealed the same sequence. — Restriction fragment multimers did not share common sequences with the satellite DNAs as judged by hybridization data. They could not be separated by isopycnic centrifugation. Furthermore these highly repeated DNAs were more complex in sequence and more variable than the satellites. Even the smallest (50 bp) fragments by depurination and other direct sequencing methods were shown to be more complex than the high molecular weight satellite peaks. — The idea that subsets of repeated DNAs may be defined by sequence complexity, possibly with discrete or separable functions, is proposed.  相似文献   

2.
DNA reassociation kinetics were studied in the European mink (Mustela lutreola), the American mink (M. vison), the marbled polecat (Vormela peregusna). Variation in DNA quantity and heterochromatin amount occurs in connection with changes in the size of all kinetic fractions. Moderately repetitive genome component is the most variable in these three species. Cryptic CsCl satellite of the stoat (M. erminea), Ag+/Cs2SO4 satellites of the M. vison, V. peregusna were used for in situ homo- and heterologous hybridizations. Satellite DNAs revealed may be classified for the evolution age and chromosomal location type. More ancient satellite DNAs were dispersed in carnivors or mammalian genomes. Mustelids' specific satellites are concentrated in heterochromatic chromosome regions. The evolutionary implications of these findings are discussed.  相似文献   

3.
Chromosomal localization of the human c-fms oncogene   总被引:7,自引:0,他引:7       下载免费PDF全文
A molecular probe was prepared with specificity for the human cellular homologue of transforming sequences represented within the McDonough strain of feline sarcoma virus (v-fms). By analysis of a series of mouse-human somatic cell hybrids containing variable complements of human chromosomes it was possible to assign this human oncogene, designated c-fms, to chromosome 5. Regional localization of c-fms to band q34 on chromosome 5 was accomplished by analysis of Chinese hamster-human cell hybrids containing as their only human components, terminal and interstitial deleted forms of chromosome 5. The localization of c-fms to chromosome 5 (q34) is of interest in view of reports of a specific, apparently interstitial, deletion involving approximately two thirds of the q arm of chromosome 5 in acute myelogenous leukemia cells.  相似文献   

4.
Mandrioli M  Colomba MS  Vitturi R 《Genetica》2000,108(2):191-195
Despite the interest of several authors, the karyotype of the labrid C. julis is still debated and in particular the presence of sex-chromosomes is still contradictory. In order to analyze the karyotype organization of C. julis we have performed an analysis with classical and molecular cytogenetic techniques. Our results after silver-, CMA3- and DAPI-staining, C-banding and fluorescent in situ hybridization (FISH) using 28S rDNA, 5S rDNA, and telomeric repeat (TTAGGG) n as probes allowed us to characterize the chromosomal location of several repetitive DNAs of C. julis. Finally, regardless of the technique used, no difference in the chromosome complement was found between males and females. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

5.
INTRoDUCTIoNlYho1iumrePensL,whiteclover,isaneconomicallyimportantplantspeciesintemperatepastures.Asbrieflyreportedby[1],ithas16pairsofchromosomes(2n=32).Asyet,nodetailedcytologicalexaminationofthisspecies,suchasC-banding,hasbeenrep0rted.Inthelastdecade,thetechnique0fC-bandinghasbeenusedt0examinehighlyrepeatedsequencesinplantchrom0s0mesandhasprovidedausefultoolf0rtheanalysis0fcyt0geneticstructureincr0pplants[2-71.Inplants,thechr0m0s0mall0calizationofhighlyrepeatedDNAsequencesbyinsituhybr…  相似文献   

6.
The physical mapping of three abundant tandemly repeated DNA sequences, CON1, CON2, and COM2, and the distributional pattern of AT- and GC-rich regions in the chromosomes of 32 species of the grass family Poaceae have been established by means of fluorescence in situ hybridization and fluorochrome banding with chromomycin and DAPI. Additionally, locations of 5S, 35S rDNA, and the C-banding pattern were examined. All satellite DNAs (satDNA) tested are situated predominantly subtelomerically in the chromosomes, but occur also colocalized with 35S and 5S ribosomal DNAs (rDNA). Especially, CON2 is most often colocalized with the 5S rDNA, but is evolutionarily not derived from it. Subtelomeric heterochromatin bands are frequently, but not always correlated with satDNA bands. Moreover, the DAPI- or rarely chromomycin-positive stainability of heterochromatin is not caused by these satDNAs as revealed by their sequence organization, showing too few clusters of AT or GC base pairs as required for binding of the fluorochromes. The occurrence of satDNAs is not correlated with that of other components of the heterochromatin. Proportions of satDNAs and other sequences of the heterochromatin relative to the entire genome appear subjected to a much faster evolutionary change than the rather stable proportions of the rDNAs. Heteromorphism in banding patterns found in many species is related in most instances with breeding system and life form. The independent evolution and amplification of different satDNAs is discussed in relation to molecular phylogenetic data. The value and limitations of satDNA data in addressing systematic questions in grasses is exemplified for several grass subfamilies and tribes.  相似文献   

7.
Neurotensin is a tridecapeptide that plays several neurotransmitter or neuromodulatory roles both in the central nervous system and in the periphery. These actions are mediated by a high-affinity receptor (Ntsr). Both rat and human cDNAs encoding high-affinity receptors have been recently cloned. The availability of Ntsr probes allowed us to localize the corresponding genes on the mouse and human chromosomes. The present data demonstrate that the Ntsr gene is assigned to the H region of the mouse Chromosome (Chr) 2 and to the long arm of the human Chr 20.  相似文献   

8.
cDNA clones encoding zinc finger motifs were isolated by screening human placenta and T-cell (Peer) cDNA libraries with zinc finger (ZNF) consensus sequences. Unique cDNA clones were mapped in the human genome by rodent-human somatic cell hybrid analysis and in some cases in situ chromosomal hybridization. ZNF 80 mapped to 3p12-3qter, ZNF 7 was previously mapped to 8q24 and is here shown by in situ hybridization and use of appropriate hybrids to map telomeric to the MYC locus. ZNF 79 mapped to 9q34 centromeric to the ABL gene and between a constitutional chromosomal translocation on the centromeric side and the CML specific ABL translocation on the telomeric side. ZNF77 mapped to 19p while ZNF 78L1 (pT3) mapped to 19q. Chromosome 19 carries many ZNF loci and other genes with zinc finger encoding motifs; the pT3 clone additionally detected a locus designated ZNF 78L2, which mapped to chromosome region 1p, most likely in the region 1p32 where the MYCL and JUN loci map.  相似文献   

9.
The physiologic and behavioral effects of pharmacologic agents that interfere with the transport of monoamine neurotransmitters into vesicles suggest that vesicular amine transport may contribute to human neuropsychiatric disease. To determine whether an alteration in the genes that encode vesicular amine transport contributes to the inherited component of these disorders, we have isolated a human cDNA for the brain transporter and localized the human vesicular amine transporter genes. The human brain synaptic vesicle amine transporter (SVAT) shows unexpected conservation with rat SVAT in the regions that diverge extensively between rat SVAT and the rat adrenal chromaffin granule amine transporter (CGAT). Using the cloned sequences with a panel of mouse-human hybrids and in situ hybridization for regional localization, the adrenal CGAT gene (or VAT1) maps to human chromosome 8p21.3 and the brain SVAT gene (or VAT2) maps to chromosome 10q25. Both of these sites occur very close to if not within previously described deletions that produce severe but viable phenotypes.  相似文献   

10.
Chromosomal localization of the human oncogene ERBA2   总被引:4,自引:0,他引:4  
The human ERBA2 gene has been mapped to chromosome 17q21.3 by in situ hybridization. A second hybridization site at 17q25 was greatly reduced by high stringency washes, indicating the presence of an additional member of the ERBA2 family at this location. Southern blot hybridization using identical conditions did not reveal additional bands, and hybridizations done at sufficiently low stringency to reveal further bands produced multiple bands rather than the single additional band expected from the in situ results. Direct comparisons of in situ and Southern hybridizations should therefore be treated with caution. The location of these two oncogenes may be significant in cases of acute promyelocytic leukaemia and acute nonlymphocytic leukaemia.  相似文献   

11.
Chromosomal localization of the human elastin gene.   总被引:4,自引:2,他引:4       下载免费PDF全文
mRNA isolated from fetal human aorta was used to synthesize cDNA that was cloned into the PstI site of pBR322. The recombinant clones were screened with an authentic sheep elastin cDNA, and one human clone that hybridized strongly was isolated and characterized. The 421-base pair (bp) insert of this human clone was sequenced by the dideoxy method, and the DNA sequence showed strong homology to the nontranslated portion of the sheep elastin cDNA. This result unequivocally identified the human clone, designated pcHEL1, as an elastin clone. Plasmid pcHEL1 labeled with [3H] nucleotides was used in in situ hybridization experiments utilizing normal metaphase chromosomes and also with cells carrying a balanced translocation between chromosomes 1 and 2: 46,XY,t(1;2)(p36;q31). The results strongly suggest that the elastin gene is localized to the q31----qter region of chromosome 2.  相似文献   

12.
DNA probes derived from rat and human proenkephalin and prodynorphin genes have been used to localize these two opiate neuropeptide genes on human chromosomes. Hybridization of probes to Southern blots made with DNAs from a rodent-human somatic-cell hybrid panel indicates localization of proenkephalin to human chromosome 8 and of prodynorphin to human chromosome 20. In situ hybridization to metaphase chromosomes confirms these assignments and indicates regional localizations of proenkephalin to 8q23-q24 and of prodynorphin to 20p12-pter. A human genomic prodynorphin clone reveals a frequent two-allele TaqI polymorphism.  相似文献   

13.
Chromosomal localization and structure of the human P1 protamine gene   总被引:4,自引:0,他引:4  
The human P1 protamine gene and mRNA were amplified with the use of the polymerase chain reaction and cloned into PTZ19R. The sequences were determined which revealed the presence of an intron. Southern and Northern hybridization analyses showed that the gene was single copy and that the mRNA was approximately 450 bases long. The gene was mapped to chromosome 16 with the use of a somatic cell hybrid panel and localized to the 21 region of the q arm by in situ hybridization of the human P1 protamine probe to human metaphase chromosomes.  相似文献   

14.
We have assigned the human histamine H1-receptor gene to chromosome 3 by Southern blot analysis of a chromosome mapping panel constructed from humanhamster somatic cell hybrids. This assignment was confirmed by in situ hybridization on metaphase chromosomes and involved bands 3p14–p21.  相似文献   

15.
Summary A novel dopamine D3 receptor gene that may be involved in psychiatric diseases has recently been characterized. It has been assigned to chromosome 3 by hybridization with a D3 receptor probe to human sorted chromosomes, and localized to band 3q 13.3 by in situ hybridization.  相似文献   

16.
It is currently thought that genetic predisposition to imbalances in dopaminergic transmission may underlie several neurological disorders, including schizophrenia, manic depression, Tourette syndrome, Parkinson disease, Huntington disease, and alcohol abuse. Originally two receptors, D1 and D2, were thought to account for all of the pharmacological actions of dopamine. However, through homology screening three additional genes, D3, D4, and D5, and two pseudogenes closely related to D5 have been characterized. To begin our genomic and evolutionary analyses of the human D5 dopamine receptor gene and its two pseudogenes, we have mapped each of them to their respective chromosomes. By combining in situ hybridization results with sequence analysis of PCR products from microdissected chromosomes, somatic cell hybrids, and radiation hybrids, we have assigned DRD5 (the locus containing the functional human D5 receptor gene) to chromosome 4p16.1, DRD5P1 (the locus containing D5 pseudogene 1) to chromosome 2p11.1-p11.2, and DRD5P2 (the locus of D5 pseudogene 2) to chromosome 1q21.1.  相似文献   

17.
Summary The localization of the human genes for cytosolic and mitochondrial aspartate aminotransferase (AspAT) has been determined by chromosomal in situ hybridization with specific human cDNA probes previously characterized in our laboratory. The cytosolic AspAT gene is localized on chromosome 10 at the interface of bands q241–q251. Mitochondrial AspAT is characterized by a multigene family located on chromosomes 12 (p131–p132), 16 (q21), and 1 (p32–p33 and q25–q31). Genomic DNA from ten blood donors was digested by ten restriction enzymes, and Southern blots were hybridized with the two specific probes. Restriction fragment length polymorphism was revealed in only one case for cytosolic AspAT, with PvuII, while no polymorphism for mitochondrial AspAT was found.  相似文献   

18.
D Z Skinner 《BioTechniques》1992,13(2):210-214
A PCR-based method is described to facilitate the identification of DNA fragments that are highly repeated and species-specific. The precision of the technique was demonstrated by cloning a fragment that occurred in a high number of copies in the plant species Medicago granadensis but in a low number of copies in 17 other Medicago species and Melilotus officinalis. This method should greatly accelerate the isolation and cloning of short and long interspersed nuclear elements with species-specific distributions. Such clones should prove useful in studies of phylogenetic relationships in the identification of interspecific hybrids, as in situ chromosome markers and other applications.  相似文献   

19.
ERV9 is a class I family of human endogenous retroviral sequences. Somatic cell hybrid genomic hybridization experiments using a mono-chromosomal panel indicate the presence of approximately 120 ERV9 loci in the human genome distributed on most chromosomes. Fluorescence in situ hybridization (FISH) using an ERV9 cDNA probe containing gag, pol and env sequences, verified this observation and a consistent signal was found at the chromosome region 11q13.3-->q13.5. By analysis of a panel of radiation hybrids, an ERV9 locus was mapped to within a 300-kbp region at the chromosome site 11q13. The marker cCLGW567 and the locus MAP3K11/D11S546 centromeric and telomeric flanked it, respectively. Northern blot analysis, using an ERV9 LTR probe, indicated that most normal tissues examined expressed low abundant ERV9 LTR driven mRNAs of various sizes. The most prominent expression was found in adrenal glands and testis. However, the level of expression varied in the same tissues among different individuals indicating that ERV9 mRNA expression probably is inducible in certain tissues or at various cell stages.  相似文献   

20.
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