The role of chromosomal HMGB proteins in plants

Proteins belonging to the chromosomal HMGA and HMGB families have been identified in a broad range of plant species. In this article, we describe the family of HMGB proteins, which, in plants, are more diversified than in other eukaryotes. There are differences between various plant HMGB proteins regarding several properties including expression pattern, DNA– and chromatin–interactions, posttranslational modifications, subcellular localisation, and interaction with other proteins, suggesting that plants have a broad repertoire of these architectural chromosomal proteins. Recent results in the Arabidopsis model system indicate that the HMGB proteins have (partially) specialised functions and are required for proper development. In addition, they are involved in plant tolerance to different stress conditions.