Gene Pairing is Advantages for Developmental Pattern Formation

Discovery seen as important for genome engineering and transcriptional research studying early embryonic development.

Gene expression is an inherently stochastic, variable process; however, organismal development and homeostasis require cells to coordinate the spatiotemporal expression of large sets of genes. In metazoans, pairs of co-expressed genes often reside in the same chromosomal neighbourhood, with gene pairs representing 10 to 50% of all genes, depending on the species. Because shared upstream regulators can ensure correlated gene expression, the selective advantage of maintaining adjacent gene pairs remains unknown. By using two linked zebrafish segmentation clock genes and combining single-cell transcript counting, genetic engineering, real-time imaging and computational modelling, the Özbudak lab showed that gene pairing boosts correlated transcription and provides phenotypic robustness for the formation of developmental patterns. Their results demonstrate that the prevention of gene pairing disrupts oscillations and segmentation, and the linkage of paired genes is essential for the development of the body axis in zebrafish embryos. Gene pairing may be similarly advantageous in other organisms, and these findings could lead to the engineering of precise synthetic clocks in embryos and organoids.

The study was published Dec. 23, 2020, in Nature.