SET8 is degraded via PCNA-coupled CRL4(CDT2) ubiquitylation in S phase and after UV irradiation

Abstract

Degradation of the histone H4 methyltransferase SET8, which regulates chromosome compaction and genomic integrity, is regulated by the CRL4(CDT2) ubiquitin ligase to facilitate DNA replication and repair.

Cyclin F suppresses B-Myb activity to promote cell cycle checkpoint control

“…Cellular fractionation. This was performed as described previously 42 . In brief, cells were lysed in CSK buffer (0.5% Triton X-100, 10 mM Pipes, pH 6.8, 300 mM sucrose, 100 mM NaCl and 1.5 mM MgCl 2 ).…”

“…Cells were grown on coverslips and treated as indicated in the figure legends. The coverslips were fixed and stained as described previously 42 . Briefly, the coverslips were fixed in 4% formaldehyde following 2 min of preextraction in Triton buffer (0.5% Triton X-100 in 20 mM Hepes, pH 7.4, 50 mM NaCl, 3 mM MgCl and 300 mM sucrose), permeabilized in 0.3% Triton X-100/PBS, blocked in 3% bovine serum albumin and incubated with phospho-H2AX-S139 (1:1,000; JBW103, Millipore) and H3S10-p (1:500, Millipore) antibodies, as indicated.…”

“…Quantitative PCR was performed as described previously 42 . In brief, RNA was purified from U2OS cells using the RNeasy kit (Qiagen).…”

A Novel Function of CRL4Cdt2

“…Cdt2 also participates in the UV-induced degradation of Cdt1, p21 (41,43), and Set8 (40). This UV-induced degradation occurs in all cell cycle phases.…”

“…Set8 plays a central role in condensation of chromosomes in G 2 /M, and its presence in S phase cells can lead to re-replication (40).…”