Discovery Finds Plants Rely on CLASSY Gene Family to Diversify their Epigenomes

A team at the Salk Institute (Salk) has shown a gene family that regulates parts of the genome that are turned off in a tissue-specific manner.

The CLASSY gene family (CLSY 1–4) essentially controls where the genome is marked by DNA methylation, the addition of methyl chemical groups to the DNA acting like tags saying, "turn off." The research team found that CLSY genes were expressed differently depending on plant tissue type. Using Arabidopsis, the Salk team discovered that the CLASSY gene family (CLSY 1–4) acts at different locations depending on the tissue, revealing how diverse patterns of methylation are generated during plant development. For example, all four CLSY genes were expressed in flower buds, while CLSY3 was strongly expressed in ovules and CLSY1 was expressed in leaf and rosette tissues.

The research team compared plants with mutant CLSY genes against wild-type plants and found that depending on the tissue, different combinations of CLSY family members, or even individual CLSY proteins, controlled small RNA and DNA methylation patterns at thousands of sites throughout the genome. The research results show the role of CLSY genes in shaping the tissues' epigenetic landscape.

For more details, read the article in Salk News.