second high mobility group (HMG)-box found in Arabidopsis thaliana high mobility group B protein 6 (HMGB6) and similar proteins
HMGB6, also called nucleosome/chromatin assembly factor group D 06 (or D 6), WRKY transcription factor 53 (WRKY53), or WRKY DNA-binding protein 53, is a master regulator of age-induced leaf senescence. It acts in a complex transcription factor signaling network regulating senescence specific gene expression; hydrogen peroxide might be involved in signal transduction. The subfamily also includes Arabidopsis thaliana HMGB13 (also known as nucleosome/chromatin assembly factor group D 13). Both HMGB6 and HMGB13 contain three HMG-box domains. This model corresponds to the second one.