Functions as transcription regulator in the hedgehog (Hh) pathway (PubMed:18455992, PubMed:26565916). Functions as transcriptional activator (PubMed:9557682, PubMed:19878745, PubMed:24311597). May also function as transcriptional repressor (By similarity). Requires STK36 for full transcriptional activator activity. Required for normal embryonic development (PubMed:15994174, PubMed:20685856). Involved in the smoothened (SHH) signaling pathway. Involved in the smoothened (SHH) signaling pathway. Involved in the smoothened (SHH) signaling pathway. Involved in the smoothened (SHH) signaling pathway. Acts as a transcriptional activator in T-cell leukemia virus type 1 (HTLV-1)-infected cells in a Tax-dependent manner. Binds to the DNA sequence 5'-GAACCACCCA-3' which is part of the Tax-responsive element (TRE-2S) regulatory element that augments the Tax-dependent enhancer of HTLV-1 (PubMed:9557682). (Microbial infection) Acts as a transcriptional activators in T-cell leukemia virus type 1 (HTLV-1)-infected cells in a Tax-dependent manner. Binds to the DNA sequence 5'-GAACCACCCA-3' which is part of the Tax-responsive element (TRE-2S) regulatory element that augments the Tax-dependent enhancer of HTLV-1 (PubMed:9557682). (Microbial infection) Acts as a transcriptional activators in T-cell leukemia virus type 1 (HTLV-1)-infected cells in a Tax-dependent manner. Binds to the DNA sequence 5'-GAACCACCCA-3' which is part of the Tax-responsive element (TRE-2S) regulatory element that augments the Tax-dependent enhancer of HTLV-1 (PubMed:9557682). (Microbial infection) Acts as a transcriptional activators in T-cell leukemia virus type 1 (HTLV-1)-infected cells in a Tax-dependent manner. Binds to the DNA sequence 5'-GAACCACCCA-3' which is part of the Tax-responsive element (TRE-2S) regulatory element that augments the Tax-dependent enhancer of HTLV-1 (PubMed:9557682). Acts as a transcriptional repressor. Interaction with ZIC1 and ZIC2 (By similarity). Interacts with STK36 (PubMed:10806483). Interacts with SUFU; this inhibits transcriptional activation mediated by GLI2 (PubMed:24311597). Interacts (via C-terminal internal region) with FOXC1 (via N-terminus); this interaction is direct and increases GLI2 DNA-binding and transcriptional activity through a smoothened (SMO)-independent Hedgehog (Hh) signaling pathway (PubMed:26565916). STK36 promotes translocation to the nucleus. In keratinocytes, it is sequestered in the cytoplasm by SUFU. In the absence of SUFU, it translocates to the nucleus. Expressed in breast cancers (at protein level) (PubMed:26565916). Isoform 1 and isoform 4 are expressed in HTLV-1-infected T-cell lines (at protein level) (PubMed:9557682). Isoform 1 and isoform 2 are strongly expressed in HTLV-1-infected T-cell lines (PubMed:9557682). Isoform 3 and isoform 4 are weakly expressed in HTLV-1-infected T-cell lines (PubMed:9557682). The N-terminal domain confers transcriptional repressor activity, while the C-terminal domain mediates transcriptional activation. Phosphorylated in vitro by ULK3. Phosphorylated by DYRK2; this inhibits GLI2 transcription factor activity and promotes proteasomal degradation of GLI2. Acetylation at Lys-757 inhibits Hh target gene expression, probably by impeding entry into chromatin thus preventing promoter occupancy. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the GLI C2H2-type zinc-finger protein family.