Satellite sequences

Fig. 3. DNA sequence used in Oak Ridge NCP structural studies. The DNA sequence of the human a-satellite sequence (A) and the a-satellite palindrome (B) for which it was a model. The palindrome is one of 24 potential phasing sequences taken from the human a-satellite DNA repeats. The center of the palindrome sequence is marked by a vertical bar. The a-satellite sequence continues to serve as the starting point for high-resolution NCP structures.

Fantes, J, Gosden, J., and Piper, J. (1988) Use of an alphoid satellite sequence to locate the X chromosome automatically, with particular reference to identification of the fragile X. Cytogenet Cell Genet. 48, 142-147. 

One of the initial methods used for food analysis was DNA hybridization. The method was based on the principle that labeled DNA from an organism should hybridize to another DNA molecule from the same source. The use of nylon membranes was necessary to provide a solid attachment environment for the DNA molecules. This method was further improved with the use of satellite sequences to distinguish meat products from closely related animals, such as sheep and goat, even if they were heat processed [50]. 

Intragenomic Distribution of Satellite DNAs. There is sufficient satellite DNA in the mouse to occupy 4 out of 40 complete chromosomes, but it is in fact distributed about equally among the different size classes of chromosomes (Maio and Schildkraut, 1969). Schildkraut and Maio (1968), however, provide evidence for enrichment in nucleolus-associated chromatin. Cytologic in-situ hybridization studies show that mouse satellite DNA is present in all chromosomes with the possible exception of the Y chromosome (Jones, 1970 Pardue and Gall, 1970). These studies also reveal that the satellite sequences are primarily localized in centromeric heterochromatin, although they do not preclude the possibility that lower concentrations of satellite sequences are dispersed throughout other regions of chromosomes. Indeed the studies of Flamm et al. (1969), which show that a small number of mouse satellite sequences are retained in main band... 

DNA, indicate that some of the satellite sequences are attached to nonsatelUte DNA and therefore that a small proportion of satellite sequences may be dispersed throughout the genome. 

There is another reason for the centromeric localization of satellite sequences which we might consider here. Ohno et al. (1968) propose that a series of tetraploidizations have occurred in the evoluation from fish to mammals, and that subsequent Robertsonian... 

Bonaccorsi S. and Lohe A. 1991. Fine mapping of satellite DNA sequences along the Y chromosome of Drosophila melanogaster Relationships between satellite sequences and fertility factors. Genetics 129 177-189. 

The size of D. melanogaster genome is 165 Mb. Approximately 21% of the entire genome is composed of simple satellite sequences which are not present in PI libraries... 

The DNA content of D. virilis is among the largest in the genus, approximately 313 Mb, 52% of which is composed of satellite sequences. Assuming a potentially clonable genome size of 150 Mb, the clones in the D. virilis library include approximately 4.4 haploid genome equivalents. 

---