Single-copy genes

Tropoelastin is encoded by a single copy gene and the alternating hydrophobic and hydrophilic domains are generally encoded by different expressed regions, or exons (Fig. 1). Those exons are alternated by introns (intragenic regions), which are... 

The DNA in a eukaryotic genome can be divided into different sequence classes. These are unique-sequence, or nonrepetitive, DNA and repetitive-sequence DNA. In the haploid genome, unique-sequence DNA generally includes the single copy genes that code for proteins. The repetitive DNA in the haploid genome includes sequences that vary in copy number from two to as many as 10 copies per cell. 

Two single copy genes coding for endoPGs are present in the C Undemuthianum genome... 

Mclnnes, J.L., Dalton, S., Vize, P.D., and Robins, A.J. (1987) Non-radioactive photobiotinlabeled probes detect single copy genes and low abundance mRNA. Bio/Technology 5, 269-272. 

Komminoth, P., Long, A. A., Ray, R., and Wolfe, H. J. (1992) In situ polymerase chain reaction detection of viral DNA, single copy genes and gene rearrangements in cell suspensions and cytospins. Diag. Mol. Pathol. 1, 85-97. 

Spann, W., Pachmann, K., Zabnienska, H., Pielmeier, A., and Emmerich, B. (1991) In-situ amplification of single copy gene segments in individual cells by polymerase chain reaction. Infection 19, 242-244. 

For repetitive DNA sequences, such as alphoid repeats, especially for identification of centromeric regions on chromosomes, as well as in mterphase nuclei, I routinely prepare labeled probes by PCR using a centromeric DNA-specific set of primers. For single-copy gene mapping by FISH, it is essential to use DNA cloned into either cosmids or in yeast artificial chromosome vectors (YAC) m order to obtain the level of sensitivity that will enable visualization of signal with a fluorescence microscope... 

For mapping single-copy genes, the incubation times in the thermal cycler should be longer. The anneal log temperature should be between 54-60°C. The incubation time may be extended to 10 min. The primer extension step at 72°C should be extended to 30 min... 

Bhatt, B, Bums, J, Flannery, D., and McGee, J. O D. (1988) Direct visualization of single-copy genes on banded metaphase chromosomes by nonisotopic in situ hybridization. Nucleic Acids Res 16,3951—3961... 

Cinti, C., Santa, S., and Maraldi, N. M (1993) Localization of single-copy gene by PRINS technique Nucleic Acids Res 21, 5799,5800. 

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