DNA packaging in eukaryotes is a tightly regulated mechanism involving a number of different proteins. Among them is HMGN1, a member of the intrinsically disordered high mobility group proteins. HMGN1 is modulated by its posttranslational modifications (PTMs), mainly lysine acetylations and serine phosphorylations. Understanding the specific influence of PTMs on the biological function of HMGN1 is a challenge, because of the difficulties of accessing homogeneous site-specifically modified HMGN1 variants. Here we present our synthetic approach to accessing HMGN1 variants bearing site-specific fluorophores, and PTMs in the nucleosome binding domain and nuclear localization signal. We investigated several semi-synthetic strategies and native chemical ligation sites for their feasibility, synthetic accessibility and efficiency. The site-specifically modified HMGN1 variants will be used to investigate the effect of the PTMs on the binding of HMGN1 to nucleosomes, the localization of HMGN1 in the cell, and conformational changes. PTM crosstalk, in which the effects of multiple PTMs interact, will be explored as well. Understanding how PTMs influence the behavior of HMGN1 in DNA packaging has the potential to provide insights into how this fundamental cellular process is regulated.