Under the Magnifying Glass: The Ups and Downs of RDNA Copy Number

Overview

Journal Semin Cell Dev Biol

Specialties Cell Biology
Reproductive Medicine

Date 2022 May 20

PMID 35595601

Authors

Selina M Kindelay

Keith A Maggert

Affiliations

Soon will be listed here.

Abstract

The ribosomal DNA (rDNA) in Drosophila is found as two additive clusters of individual 35 S cistrons. The multiplicity of rDNA is essential to assure proper translational demands, but the nature of the tandem arrays expose them to copy number variation within and between populations. Here, we discuss means by which a cell responds to insufficient rDNA copy number, including a historical view of rDNA magnification whose mechanism was inferred some 35 years ago. Recent work has revealed that multiple conditions may also result in rDNA loss, in response to which rDNA magnification may have evolved. We discuss potential models for the mechanism of magnification, and evaluate possible consequences of rDNA copy number variation.

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