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

aziz F: c.ll crd. cdtd 0t H4 Gene tansctibtlon
lhese cel types contain detedable levels ot HiNF M, -P and -O when aclively
prolilorating. Tho resuis show that th€ magnitude of mutaliona ofiects lor
each oi lhe mutants is very similff in each cell type (Fig. 28). Thus, lhe relaljve
imporlanco ol lranscrlplional recogni on molils and cognate fadors in these
hree prolileratng cell types is quantitritively similar, rcgatdlsss ot difterences
in th€ expression of lissLro-sp€cllic and cell growlh r€laled PhenotyPic
aboltshment ol specitrc H4-slls llfscognltion motrs is dominanlover
€ltecis on ih9 pulative spatiat gllgnmenls ol H4 iranscrlptlon laclofs
we tested a set ot lhree additional H4.site ll promoler mulants ocN-
12, FAM-14 and FAM-15) by gel shitt assays. Mutarn TCN-12 contains $ree
nuclgotid€ subslitltions al spscific posilio.s in site ll, which do .ot affecl
blnding or the thfee H4-site ll bndifg proieins (F,9. 26). However, FAIV-14
conra ns an additiona precise delelion ol nt-80, which resulls n abolishmentof
HiNF P/84-TF2 bi.dng bur has no eilect on eilher HiNF M/lBF.2 or HiNF-M
(Fig 26). FAMr 5 contalns an additional short deletion in the distal terminus ol
H4-Siie ll which abrogales H|NF-M/|FF-2 binding, but does not allecl HiNF
P/H4'TFz or HiNF-D (Fig. 26). rhus, thess prolein/DNA interaction sludies
iunhe. delne rhe blnding sits rsquir€ments ol HiNF-M/lRF-z and HNF-P/84'
TF2, and 6how thar FAMr4 and FAl\,4-15 reprssent iactoFspecilic promoier
nulants wilh alle€d spacing ol laclors binding at sne ll
Funclional analvsis ol the FAM-14 promoler shows thal lra.scriptjonal
adivity ol rh€ FAM-I4ICAT construcl is approximately equivalent lo thal ot
€onsrucls TM-3/CAT and TCNj2/CAT, This rcsllt indicates lhal abfogation
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