Asynchronous Replication, Mono-Allelic Expression, and Long Range Cis-Effects of ASAR6
Figure 2
Coordinated asynchronous replication timing on chromosome 6.
A) Schematic representation of the ReTiSH assay. PBLs were exposed to BrdU during the entire length of S phase (14 hours) or only during late S phase (6 hours). The ReTiSH assay can distinguish between alleles that replicate early (E) and late (L) in S phase. B–G) Mitotic spreads were hybridized with three different FISH probes. First, each ReTiSH assay included a centromeric probe to chromosome 6. Arrows mark the centromeric signals in each panel. Each assay also included BAC probes representing asynchronously replicating loci on chromosome 6. The insets in each panel show the two chromosome 6 s aligned at their centromeres. B and C) ReTiSH assay using an ASAR6 BAC (RP11-374I15; green) plus a FUT9 BAC (RP11-75N19; red). The ASAR6 and FUT9 BACs show hybridization signals to the same chromosome 6 at the 6 hour time point. D and E) ReTiSH assay using an ASAR6 BAC (RP11-374I15; green) plus a BAC (RP11-150A6; red) containing the olfactory receptor genes OR14J1, OR5V1, OR12D3 and OR12D2. The ASAR6 BAC and the OR BAC show hybridization signals to the same chromosome 6 s at the 6 hour time point. F and G) ReTiSH assay using an HLA BAC (RP11-166F24; red) plus a ME1 BAC (RP11-703G14; green). HLA and ME1 show hybridization signals on the opposite chromosome 6 s at the 6 hour time point, indicating that HLA and ME1 display trans coordination of asynchronous replication.