Exon junction complexes regulate osteoclast-induced bone resorption by influencing the NFATc1 m6A distribution through the “shield effect”

Abstract

	•METTL14 controls osteoclast-mediated bone resorption by means of the methylation (4249 A) of the NFATc1 gene during osteoclast differentiation.
	•Exon junction complexes (EJCs) protect the remaining methylation sites of the NFATc1 gene (located in the inner exon fragment of 50–200 nt) from hypermethylation and degradation.
	•The “shield effect” disappears when the exon fragment is extended to 300 nt. Downstream, YTHDF2 induced the degradation of hypermethylation NFATc1 transcripts without site restriction.

Keywords

exon junction complexes / m6A distribution characteristics / osteoclast / osteoporosis / shield effect

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2025 The Author(s). Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.