Methylation induced premeiotically

In molecular biology, methylation induced premeiotically (MIP) is a process by which cytosines within repeated DNA sequences are "de novo" methylated prior to the sexual cycle. This process was first described in the ascomycete "Ascobolus immersens". MIP is dependent upon the gene "masc1" which encodes a cytosine methyltransferase-like protein.
At least one major function of the process appears to be genome defense. Related functions have been found in other fungi, including "Neurospora" and "Aspergillus" species.