Page 1 \ ?^p 6r.1 CELL CYCLE CONTROL OF HUMAN H4 ...

Aziz F: C.tl C1lcte Cotu.t ot H1 C4n6 r6Mbn@
ot the HiNF-P/H4 TF2 interaclion silh H4.Sit6 I rogelher with lhe @ncominanl
ahe,alion of the spacing belr€en the M-box and the TATA-box, does ^ot havg
a signilicant eff€cl on H4 promotff activity (Fig, 29). The simjlarili€s in lhs
.esulls lor lhe liNF P/H4TF-2 mutani promolers GT-g and FAIV-14 (Figs. 28,
29) co oborate tiie conclLrson lhat H|NF-P/H4TF-2 do€s not contribute
siqnilicanty lo lhe level of H4 gene transcription when othef Sts ll taclors
rcmair capable oi binding. lvor€over, lh€ ditf€r€nce in spacing ol lho lV- and
TATA-box berween $ese consructs, which could alter possible inreradlons ot
HiNF.M wirh TATA bjnding protein TFtt-O, does nor significanily afiect rh8
olncome ol lhe resulls.
h c$mrasr, the FAM-15/oA1 conslrlcr is expressed ai a 3 lold r€duced
l€v€l rolative lo the wiidtype TM-3/CAT consl.ucl. Th€ lhrce lold reduction in
report€r gene expression obtained wth both INSJo/oAT and FAMn5/CAT
(Figs.3 and 4), whch each repr€s6nl H|NF-M/|BF-2 mltant prornol€rs,
supponsour modelin which th€ HiNF,M/laF-2 inle.acion wilh H4-sire llplays
a key roie in determining lhe level ol H4 transcriplion. In addition, the otfocts
obsetued with the rNs-10 and FAM-15 promoters are quantirively simjlar,
ahhough lhese conslrucrs diller in the spacing wilhin Sile ll and between Siles
I and ll which @dd change sparial intoracrions betwee. F_omorer ladors srill
Taken togelher, ihe s milaril ss n resuts lor GT-g versus FAIV- 1 4 and
INS-10 v€rsus FAlv 15 in three d fier€.r c6l typ€s ars cons slenl wirh th€
concept that difierences in th€ spalial alignmenis oi histone H4 gen€
129