KLF/Sps are a family of transcription factors that contain three carboxyl-terminal (C-terminal) C2H2-type zinc finger structural motifs that bind to the GC-rich regions in DNA and regulate various cellular functions, such as proliferation, differentiation, and apoptosis, as well as the development and homeostasis of several types of tissue. The C-terminal end binds to the promoter and enhancer regions of a gene. Each KLF also has a unique amino-terminal (N-terminal) end that acts as the functional domain that allows it to bind specifically to a certain partner. KLFs share the similar function of transcription regulation via the recruitment of regulatory proteins. These transcription factors have a conserved structural homology between mammalian species, which allow for similar function due to similar protein interaction motifs at the N-terminal domains. The C-terminal end is also highly conserved with both the first and second zinc finger have 25 amino acids, while the third has 23 amino acids. Each of the three zinc fingers recognize three unique base pairs for their DNA-binding sites, which together make the general form NCR CRC CCN (where N is any base and R is a purine). There is some evidence that positively-charged amino acids within the three zinc fingers may contribute towards localizing the protein in the Nucleus. The N-terminal end allows for the binding of various coactivators, corepressors, and modifiers. All family members share the zinc finger signature KLF-DBD of codice_1 and use a 9aaTAD.