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

A21z F: C.tl Cvcte Cdtat at H4 Gqe tu$cti rid
rh€ e{e.t ro whlch h4 promorers are activ€. B€caus8 the lNs 10 promol€r
rcpresents a specilic H|NF-M/|FF-2 r€cogniton site mulart, the obserued
dec.ease in reporler gen€ exprssson wnh lhe INS-1o/CAT conshuct
sugg€sls that HiNF-r\4/ BF-z is importani ior hlgh level H4 gene lfanscription
However, fte efect observed wilh lh€ INS-10 promoter is several-told less
than rhat obrain€d wilh lh€ Mc-7 promotor. This indicales that addi onal site ll
laciors contribute to lulacrlviry of rh€ H4 promoter. w€ nole that th€ lwo
inseruons in Sito ll embod ed by mltant INS-10 pol€ aly may aliecl the
spaiial alignmenr ol orher histone gene promoter lactols interacting wilh Sites I
and ll. Additional M.box muhnts werc assayed to excrude this contoundidg
lactor lor a deiinltiv€ conclusion (see b6low).
absence of a statisll€lly signilica effecl on ranscription lor mllant
su8-11 suggests rhat the role ot HiNF-o, simjlar to HiNF-P/H4TF-2, in
mBdiaring high levels ol hisron€ H4 gene kanscripion is limited. The rosults
obtained wllh the INS-10 and SUB.11 promoter mulants suggests that dist nct
types ol natural soquence varialion b€tween human H4 genes hav€ dili€rent
ettecls on H4 gene lranscdption.
Slmllarllles in muratonal stlacls on H4 genetranscnptlon in dlstlncl
prollt€rating csu lypes dlsprayrng dliterent cell gfowlh and tissuesp6cnic
phenotyprc properties
The MC-7, GT€, rNS-10 and SUBnI muranl CAT construcG wers also
analyzed in FOS 17/2.8 osteosarcoma c€lls and normal diploid calvadal
osreoblasrs (FoB) ro assess smilarres in mulalional efiects on H4 gsn€
rranscriprion in diiieient cell rypes. similar to HeLa s3 ceruical carcinoma cells,
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