Ladder-like amplification of the type I interferon gene cluster in the human osteosarcoma cell line MG63.
The organization of the type I interferon (IFN) gene cluster (9p21.3) was studied in a human osteosarcoma cell line (MG63). Array comparative genomic hybridization (aCGH) showed an amplification of approximately 6-fold which ended at both ends of the gene cluster with a deletion that extended throughout the 9p21.3 band. Spectral karyotyping (SKY) combined with fluorescence in-situ hybridization (FISH) identified an arrangement of the gene cluster in a ladder-like array of 5-7 'bands' spanning a single chromosome termed the 'IFN chromosome'. Chromosome painting revealed that the IFN chromosome is derived from components of chromosomes 4, 8 and 9. Labelling with centromeric probes demonstrated a ladder-like amplification of centromeric 4 and 9 sequences that co-localized with each other and a similar banding pattern of chromosome 4, as well as alternating with the IFN gene clusters. In contrast, centromere 8 was not detected on the IFN chromosome. One of the amplified centromeric 9 bands was identified as the functional centromere based on its location at the chromosome constriction and immunolocalization of the CENP-C protein. A model is presented for the generation of the IFN chromosome that involves breakage-fusion-bridge events.
Marella
Narasimharao V
NV
Department of Biological Sciences, University at Buffalo, State University of New York, Buffalo, NY 14260, USA.
Zeitz
Michael J
MJ
Malyavantham
Kishore S
KS
Pliss
Artem
A
Matsui
Sei-ichi
S
Goetze
Sandra
S
Bode
Juergen
J
Raska
Ivan
I
Berezney
Ronald
R
D045744:Cell Line, Tumor; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics; D020223:Chromosome Painting; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D055028:Comparative Genomic Hybridization; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007370:Interferon Type I / Q000235:genetics*; D007621:Karyotyping; D005810:Multigene Family / Q000235:genetics*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*
D002868:Chromosomal Proteins, Non-Histone; D007370:Interferon Type I; C060905:centromere protein C