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Almost all galaxies along the Hubble sequence host a Compact Massive Object in their center,in the form of either a supermassive black hole(SMBH)or a very dense stellar cluster(commonly referred to as Nuclear Star Cluster,NSC).The actual relation among SMBHs and NSCs is poorly known,but it is clear that the possibility that they co-exist in the same nucleus depends on the host mass: galaxies with mass below 1010 M⊙ generally host a NSC,while heavier galaxies,with masses above 1011 M⊙,seem to contain only a central SMBH; NSCs and SMBHs co-exist only for intermediate values of the host mass.A possible scenario for the formation of a NSC is the so-called “migratory dry-merger” scenario,in which globular clusters(GCs)decay toward the center of the host galaxy by dynamical friction and merge,to form a very massive stellar cluster.Within this framework,a possible explanation for the lack of NSCs in high-mass galaxies is the destruction of the incoming GCs caused by the intense tidal field of the central SMBH,suppressing the formation of the NSC.In this talk,I show preliminary results of high-resolution direct N-body simulations,performed using HiGPUs,which investigate the effects of a central SMBH on a single “typical” GC orbiting around it.By consistently varying either the mass of the SMBH and the mass of the host galaxy,I derived an upper limit to the mass of the central SMBH,and thus to the mass of the host,above which the formation of a NSC is impossible in the migratory model.