Physical mapping

Radiation hybrid mapping Now the most rapid method of localizing a gene or DNA fragment to a subregion of a human chromosome and constructing a physical map. 

DNA sequencing Establishes the highest resolution physical map. Identifies open reading frame. Facilities with many high throughput instruments could sequence millions of base pairs per day. 

Biological Effects of Low Level Exposures (BELLE). www.BeUeQuliae.com BLACKSTOCK w p and WEIR M p (1999) Proteomics quantitative and physical mapping of cellular proteins. TIBTECH 17 121-7. 

Fig 1 Physical map of the A. irakense genome containing pectinolytic genes... 

Fig. 4. Schematic organization of the Shaker K channel gene. The coordinates of the physical map are as in [9]. The direction of transcription is indicated by arrows. Approximate location of exons is given by boxes. Open box corresponds to noncoding exons, lettered boxes to alternative amino-terminal ends of Shaker channel proteins and the core region, respectively, numbered boxes to the two alternative carboxy-terminal ends. Exon numbers are as in [53].

Don RH, JM Pemberton (1985) Genetic and physical map of the 2,4-dichlorophenoxyacetic acid-degradative plasmid pJP4. J Bacteriol 161 466-468. 

Ahmad D, R Masse, M Sylvestre (1990) Cloning, physical mapping and expression in Pseudomonas putida of 4-chlorobiphenyl transformation genes from Pseudomonas testosteroni strain B-356 and their homology to the genomic DNA from other PCB-degrading bacteria. Gene 86 53-61. 

BLACKSTOCK, W.P., WEIR, M.P., Proteomics quantitative and physical mapping of cellular protiens, Trends in Biotech., 1999,17,121-127. 

Clifford, R., et al., "Expression-Based Genetic/Physical Maps of Single Nucleotide Polymorphisms Identified by the Cancer Genome Anatomy Project," Genome Res., 10, 1259-1265 (2000). 

Yu, A., et al., "Comparison of Human Genetic and Sequence-Based Physical Maps," Nature, 409, 951-953 (2001). 

Physical Mapping of Quantitive Trait Loci in Raspberries... 

Figure 5-48 A physical map of the oxi3 locus of yeast mitochondrial DNA. The restriction fragments used for DNA sequencing are indicated by the arrows. The extent to which the sequences were read is represented by the lengths of the arrows. The map units are shown in the inner circle. The following symbols, together with the names of the restriction enzymes (Chapter 26), are used for the restriction sites ...

The directions of transcription of certain operons are indicated by the arrows. The 1983 version of this map76 contained 1027 loci and we now know the location of all of the more than 4300 genes. (B) Physical map of the E. coli chromosome obtained by study of large 20-100 kb fragments obtained by digestion with restriction endonuclease Notl and separated by pulsed field gel... 

Let us now consider how knowledge of bacterial sex factors and of phage K permitted the mapping of bacterial chromosomes. Together with the use of restriction endonucleases these techniques gave us the first precise physical maps of bacterial chromosomes and pointed the way toward the determination of complete genome sequences. 

The calibration of the E. coli genetic map in minutes was a temporary expedient. It was followed by physical maps expressed directly as micrometers of DNA length (total length 1.6 mm) or thousands of nucleotide units (kb). A physical map obtained by restriction enzyme mapping is shown in Fig. 26-4B. To obtain this map DNA fragments were prepared using specific restriction endonucleases (Section E, 1). 

DNA has been substituted in one strand.98 Since distances can be measured accurately on the electron micrographs, rather precise ( 50-100 bp) physical maps can be obtained. The chromosome map of phage K was mapped in this way initially now its complete nucleotide sequence is known. Another electron microscopic method is useful for location of AT-rich regions that denature readily. In a suitable concentration of formamide these regions melt to form visible single-stranded denaturation loops similar to the bubbles in Figure 26-6. 

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