Table 2.
Line | Artificial chromosomes | Heterochromatin | Euchromatin | |||
Alpha-satellite | Size estimate* | H3 TrimK9/K27 | HP1α | H3DimK4 | †CENP-A | |
17-E29 | D17Z1 | 1-3 Mb | - | (-) | + | + |
17-D34 | D17Z1 | 1-3 Mb | - | (-) | + | + |
17-B12 | D17Z1 | 3-10 Mb | + | + | + | + |
17-C20‡ | D17Z1 | 3-10 Mb | + | + | + | + |
X-4 | DXZ1 | 10-20 Mb | + | ND | + | ND |
X-5 | DXZ1 | 10-20 Mb | + | ND | + | ND |
Host controls | ||||||
17 cen | + | + | - | + | ||
X cen | + | ND | - | + |
Summary of results obtained by immunofluorescence staining on metaphase chromosomes containing artificial chromosomes using antibodies to either heterochromatin (H3TrimK9/K27; HP1α) or euchromatin (H3DimK4) components (Figures 1-3). + positive staining; - signal not detectable; (-) weak staining comparable to general arm staining; ND, not done. *Comparison of alpha satellite signal intensities (using FISH analyses) on the artificial chromosomes with those of the relevant host centromere regions was used to estimate artificial chromosome sizes. †CENP-A stains uniformly on artificial chromosomes and at a level comparable to the host staining level [12]. Controls, staining pattern at either host 17 or X centromere regions overlapping with D17Z1 or DXZ1 probes (respectively). ‡17-C20 contains mitotically unstable artificial chromosomes (Table 1).