Scaffolding proteins play a central role in many regulatory cellular networks, where signalling proteins trigger different, and even orthogonal biological pathways. Such biological regulatory networks can be duplicated by multiplexer/demultiplexer logic operations. We present the use of libraries of Mg2+-dependent DNAzyme subunits as computational moduli for the construction of 2:1 and 4:1 multiplexers and a 1:2 demultiplexer. In the presence of the appropriate inputs, and the presence or absence of selector units, the guided assembly of the DNAzyme subunits to form active Mg 2+-dependent DNAzyme proceeds. The formation of the active DNAzyme nanostructures is controlled by the energetics associated with the resulting duplexes between the inputs/selectors and the DNAzyme subunits. The library subunits are designed in such a way that, in the presence of the appropriate inputs/selectors, the inputs are knocked-down or triggered-on to yield the respective multiplexer/demultiplexer operations. Fluorescence is used as the readout for the outputs of the logic operations. The DNAzyme-based multiplexer/demultiplexer systems present biomolecular assemblies for data compression and decompression.