Tousled-like kinases phosphorylate Asf1 to promote histone supply during DNA replication

TY - JOUR

T1 - Tousled-like kinases phosphorylate Asf1 to promote histone supply during DNA replication

AU - Kamalyukova, Ilnaz M

AU - Young, Clifford

AU - Strømme, Caroline B

AU - Menard, Patrice

AU - Jasencakova, Zusana

AU - Mejlvang, Jakob

AU - Ask, Katrine

AU - Ploug, Michael

AU - Nielsen, Michael L

AU - Jensen, Ole N

AU - Groth, Anja

PY - 2014/3/6

Y1 - 2014/3/6

N2 - During DNA replication, nucleosomes are rapidly assembled on newly synthesized DNA to restore chromatin organization. Asf1, a key histone H3-H4 chaperone required for this process, is phosphorylated by Tousled-like kinases (TLKs). Here, we identify TLK phosphorylation sites by mass spectrometry and dissect how phosphorylation has an impact on human Asf1 function. The divergent C-terminal tail of Asf1a is phosphorylated at several sites, and this is required for timely progression through S phase. Consistent with this, biochemical analysis of wild-type and phospho-mimetic Asf1a shows that phosphorylation enhances binding to histones and the downstream chaperones CAF-1 and HIRA. Moreover, we find that TLK phosphorylation of Asf1a is induced in cells experiencing deficiency of new histones and that TLK interaction with Asf1a involves its histone-binding pocket. We thus propose that TLK signalling promotes histone supply in S phase by targeting histone-free Asf1 and stimulating its ability to shuttle histones to sites of chromatin assembly.

AB - During DNA replication, nucleosomes are rapidly assembled on newly synthesized DNA to restore chromatin organization. Asf1, a key histone H3-H4 chaperone required for this process, is phosphorylated by Tousled-like kinases (TLKs). Here, we identify TLK phosphorylation sites by mass spectrometry and dissect how phosphorylation has an impact on human Asf1 function. The divergent C-terminal tail of Asf1a is phosphorylated at several sites, and this is required for timely progression through S phase. Consistent with this, biochemical analysis of wild-type and phospho-mimetic Asf1a shows that phosphorylation enhances binding to histones and the downstream chaperones CAF-1 and HIRA. Moreover, we find that TLK phosphorylation of Asf1a is induced in cells experiencing deficiency of new histones and that TLK interaction with Asf1a involves its histone-binding pocket. We thus propose that TLK signalling promotes histone supply in S phase by targeting histone-free Asf1 and stimulating its ability to shuttle histones to sites of chromatin assembly.

U2 - 10.1038/ncomms4394

DO - 10.1038/ncomms4394

M3 - Journal article

C2 - 24598821

SN - 2041-1723

VL - 5

SP - 3394

JO - Nature Communications

JF - Nature Communications

ER -