Protamines are small, arginine-rich, nuclear proteins that replace histones late in the haploid phase of spermatogenesis and are believed essential for sperm head condensation and DNA stabilization. Mice, humans, and certain fish have 2 or more different protamines, whereas the sperm of bull, boar, rat, rabbit, guinea pig, and ram have one form of protamine. The 2 human protamines are denoted PRM1 and PRM2.

When mixed with insulin, protamines slow down the onset and duration of insulin action (see NPH insulin).

See also

• Protamine sulfate

プロタミン | protaminy

Proteins