A system for the controlled clustering of gene regulatory proteins at specific target genomic loci, comprising: a first structure comprising; (i) a first segment having a Cas-based genomic targeting protein fused or attached to one or more first sequences, each first sequence including at least one sequence selected from the group consisting of a light-sensitive receptor, a chemical-sensitive receptor, and a light-sensitive oligomerization protein; or (ii) a first segment having a Cas-based genomic targeting protein fused or attached to one or more genes encoding at least one protein sensitive to at least one wavelength of light and a second segment fused to the first segment, the second segment having at least one sequence selected from the group consisting of a low complexity sequence, an intrinsically disordered protein region, a synthetic or natural nucleic acid binding domain, and at least one repeatable sequence, wherein the repeatable sequence comprises a linker fused to at least one additional gene encoding at least one protein sensitive to at least one wavelength of light; and a second structure comprising a second sequence selected from the group consisting of a cognate partner of the light-sensitive receptor protein, a cognate partner of the chemical-sensitive protein, and a dimerization domain complementary to a dimerization module, the second sequence being fused to at least one transcriptional regulatory protein having a full length or truncated low complexity or intrinsically disordered protein region, wherein the protein system is configured for targeted condensation at the specific target genomic loci by exposing the protein system to at least one predetermined wavelength of light, a chemical to which the chemical-sensitive receptor is sensitive, or a combination thereof. a first structure comprising; (i) a first segment having a Cas-based genomic targeting protein fused or attached to one or more first sequences, each first sequence including at least one sequence selected from the group consisting of a light-sensitive receptor, a chemical-sensitive receptor, and a light-sensitive oligomerization protein; or (ii) a first segment having a Cas-based genomic targeting protein fused or attached to one or more genes encoding at least one protein sensitive to at least one wavelength of light and a second segment fused to the first segment, the second segment having at least one sequence selected from the group consisting of a low complexity sequence, an intrinsically disordered protein region, a synthetic or natural nucleic acid binding domain, and at least one repeatable sequence, wherein the repeatable sequence comprises a linker fused to at least one additional gene encoding at least one protein sensitive to at least one wavelength of light; and (i) a first segment having a Cas-based genomic targeting protein fused or attached to one or more first sequences, each first sequence including at least one sequence selected from the group consisting of a light-sensitive receptor, a chemical-sensitive receptor, and a light-sensitive oligomerization protein; or (ii) a first segment having a Cas-based genomic targeting protein fused or attached to one or more genes encoding at least one protein sensitive to at least one wavelength of light and a second segment fused to the first segment, the second segment having at least one sequence selected from the group consisting of a low complexity sequence, an intrinsically disordered protein region, a synthetic or natural nucleic acid binding domain, and at least one repeatable sequence, wherein the repeatable sequence comprises a linker fused to at least one additional gene encoding at least one protein sensitive to at least one wavelength of light; and a second structure comprising a second sequence selected from the group consisting of a cognate partner of the light-sensitive receptor protein, a cognate partner of the chemical-sensitive protein, and a dimerization domain complementary to a dimerization module, the second sequence being fused to at least one transcriptional regulatory protein having a full length or truncated low complexity or intrinsically disordered protein region, wherein the protein system is configured for targeted condensation at the specific target genomic loci by exposing the protein system to at least one predetermined wavelength of light, a chemical to which the chemical-sensitive receptor is sensitive, or a combination thereof.