TY - JOUR
T1 - Molecular organization and chromosomal location of human GC-rich heterochromatic blocks
AU - Meneveri, Raffaella
AU - Agresti, Alessandra
AU - Marozzi, Anna
AU - Saccone, Salvatore
AU - Rocchi, Mariano
AU - Archidiacono, Nicoletta
AU - Corneo, Gianmarco
AU - Valle, Giuliano Delia
AU - Ginelli, Enrico
PY - 1993/1/30
Y1 - 1993/1/30
N2 - From the sequencing of three genomic DNA fragments and PCR amplification products from total human DNA, we have derived the sequence of a 545-bp Sau3A fragment (68% GC), representative of a family of human DNA repeats. Since previous studies suggested its linkage with unrelated Sau3A repeats of 68 bp (54% GC) (β-satellite sequences), this feature was further investigated by in situ hybridization experiments and by Southern blot analysis of a panel of DNAs from human-Chinese hamster somatic cell hybrids. Both DNA repeats are preferentially localized on the heterochromatic regions of acrocentric chromosomes, on the pericentromeric heterochromatin of chromosome 1, 3 and 9, and on the proximal euchromatic region of the chromosome Y q arm. On chromosome 9, both repeats are part of a 2.7-kb higher-order repeat unit. These results and the Southern blot analysis on partial digests of total DNA, suggest that the linkage between the two repetitive DNA sequences is a constant feature throughout the genome. Furthermore, Southern blot analysis of HpaII-digested and MspI-digested DNA from different human tissues and tumor cell lines indicates that the investigated heterochromatic blocks appear to be subjected to changes in their methylation pattern.
AB - From the sequencing of three genomic DNA fragments and PCR amplification products from total human DNA, we have derived the sequence of a 545-bp Sau3A fragment (68% GC), representative of a family of human DNA repeats. Since previous studies suggested its linkage with unrelated Sau3A repeats of 68 bp (54% GC) (β-satellite sequences), this feature was further investigated by in situ hybridization experiments and by Southern blot analysis of a panel of DNAs from human-Chinese hamster somatic cell hybrids. Both DNA repeats are preferentially localized on the heterochromatic regions of acrocentric chromosomes, on the pericentromeric heterochromatin of chromosome 1, 3 and 9, and on the proximal euchromatic region of the chromosome Y q arm. On chromosome 9, both repeats are part of a 2.7-kb higher-order repeat unit. These results and the Southern blot analysis on partial digests of total DNA, suggest that the linkage between the two repetitive DNA sequences is a constant feature throughout the genome. Furthermore, Southern blot analysis of HpaII-digested and MspI-digested DNA from different human tissues and tumor cell lines indicates that the investigated heterochromatic blocks appear to be subjected to changes in their methylation pattern.
KW - human/hamster hybrids
KW - in situ hybridization
KW - methylation
KW - Recombinant DNA
KW - repetitive DNA sequences
KW - β-satellite sequences
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U2 - 10.1016/0378-1119(93)90128-P
DO - 10.1016/0378-1119(93)90128-P
M3 - Article
C2 - 8428662
AN - SCOPUS:0027518492
VL - 123
SP - 227
EP - 234
JO - Gene
JF - Gene
SN - 0378-1119
IS - 2
ER -