Transcription of genes is controlled by a highly tuned machinery regulated by transcription factors, histone modifications and chromatin remodelers. CHD3, as a member of the chromatin remodelers, has an important role in modifying the dynamics of the chromatin structure. As a part of the NuRD complex, it has a repressive effect on transcription, while when functioning alone it is associated with transcriptional activation, as it was described for its interaction with the transcription factor c-Myb. Another player in these processes linked to both transcriptional repression and chromatin is the SUMO network, whereby SUMO conjugation and deconjugation are tuning and controlling many interactions in the transcription system. The main objective of the project was to study the function of CHD3 in a SUMO network context. This thesis followed up some preliminary findings of the interaction of CHD3 with different proteins in the SUMO pathway, and to achieve a better understanding, we decided to investigate those interactions in more detail and how they can affect transcription. As described previously, the transcription factor c-Myb can be posttranslationally modified by SUMO isoforms and has a reported interaction with CHD3. First, we confirmed and mapped CHD3 interactions by GST pulldown analysis. Then, we performed reporter assays to study the implication of those interactions in transcription. We concluded that CHD3 has an important role in linking the SUMO network to both chromatin remodeling and transcription. We suggest a unifying model that combines these interaction events as part of a single mechanism that may guide future research in these matters.