baySeq considered the variance in the three biological replicates when estimating the likelihood, and assigned genes into the model that best described their cell cycle expression profile.
Cells that have a stable modal chromosome number and are not highly aneuploid, such as the human myeloid leukaemia K562 cells, (Chen, 1985) make the best candidates for cell cycle phase separation by centrifugal elutriation and it was possible to obtain G1, S and G2 fractions that were 85% pure (Supplementary Figure 2).
Remarkably, studies correlating pRb loss with adherens junction disruption have been largely unnoticed, and while pRb has been best characterized as a cell cycle regulator and its participation in developmental processes is still the subject of intense research, no molecular mechanism has been proposed to account for the correlation between pRb loss and adherens junction abnormalities.
Since mitotic cells account for only a tiny fraction of a freely cycling cell population (mitosis lasts 1 hour out of a 24 hour cell cycle), the best way to examine the mechanics of mitosis without the potential side-effects of inhibitors is to simply observe cells dividing.
This signal was best observed in upregulation and cell cycle gene sets (Figure 6Cand E), yet subtle enrichment in transgenic promoters could also be detected in specific downregulation (Figure 6B) and specific upregulation, where the FREAC2 motif ranked among the top 15 PWMs (Table S4).
Xenopus and Drosophila, two of the best-studied models for embryonic cell cycle regulation, are hardly representative of all metazoan.
The best-known Skp2 substrate is cell cycle inhibitor p27, which is targeted by Skp2SCF for ubiquitination and degradation when threonine 187, located at the C-terminal end of p27, is phosphorylated [16]– [16].
In mammals, D-type cyclins bound to Cdk4 or Cdk6 are best characterized for their functions during cell cycle progression, but several reports have shown additional roles, in particular the regulation of multiple transcription factors by direct binding [50].
The best characterized partners of pRB in cell cycle regulation belong to the E2F family of transcription factors.
