Editing Histone (section)

=== Link between cell-cycle control and synthesis ===
Nuclear protein Ataxia-Telangiectasia (NPAT), also known as nuclear protein coactivator of histone transcription, is a transcription factor which activates histone gene transcription on chromosomes 1 and 6 of human cells. NPAT is also a substrate of cyclin E-Cdk2, which is required for the transition between G1 phase and S phase. NPAT activates histone gene expression only after it has been phosphorylated by the G1/S-Cdk cyclin E-Cdk2 in early S phase.<ref>{{cite journal | vauthors = Zhao J, Kennedy BK, Lawrence BD, Barbie DA, Matera AG, Fletcher JA, Harlow E | title = NPAT links cyclin E-Cdk2 to the regulation of replication-dependent histone gene transcription | journal = Genes & Development | volume = 14 | issue = 18 | pages = 2283–97 | date = September 2000 | pmid = 10995386 | pmc = 316937 | doi = 10.1101/GAD.827700 }}</ref> This shows an important regulatory link between cell-cycle control and histone synthesis.