Protamines – histones in disguise

All DNA from yeast to mammals is occupied by histones (H2A, H2B, H3, and H4) and folded into chromatin. Well, not entirely…. Certain types of DNA such as sperm DNA play by their own rules and are actually compacted by proteins other than histones! Most of the paternal DNA in human sperms is compacted with the help of protamines (protamine P1 and P2).  I would still count them as histone-like proteins as protamines are also small (5-8 kDa in [...]

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