Chromatin anchor protein which binds to methylated lysine residues on histone H3, thereby recruiting heterochromatin to the nuclear periphery, especially in embryonic cells, with a lesser role in differentiated cells (PubMed:26607792, PubMed:31118512). May be required for the correct positioning of chromatin and nucleoli in embryos (PubMed:26607792). Interacts with mono-, di- and tri-methylated 'Lys-9' residues on histone H3. Weakly interacts with methylated 'Lys-37' residues on histone H3. Expressed at all developmental stages from embryogenesis to adulthood. Evenly expressed in most tissues during the L1 stage of larval development, however, expression is weak in the intestine and high in muscle. Reduced anchoring of heterochromatin to the nuclear periphery which is exacerbated on an mrg-1 mutant background and is partially blocked by RNAi-mediated knockdown of cbp-1 or atf-8 (PubMed:26607792, PubMed:31118512). Altered nucleolar localization with nucleoli positioned away from the nuclear periphery (PubMed:26607792). When exposed to hlh-1, a transcription factor that induces muscle differentiation, 25% of embryos continue to develop and the embryonic cells do not transdifferentiate into muscle-like cells like their wild-type counterparts (PubMed:26607792).