Shadow enhancer explained

Shadow enhancers are groups of two or more enhancers that control the same target gene and drive overlapping spatiotemporal expression patterns.^{[1] [2] [3]} Shadow enhancers are found in a wide range of organisms, from insects to plants to mammals, particularly in association with developmental genes.^{[4] [5] [6] [7]} While seemingly redundant, the individual enhancers of a shadow enhancer group have been shown to be critical for proper gene expression in the face of both environmental and genetic perturbations. Such perturbations may exacerbate fluctuations in upstream regulators.^{[1] [8] [9]}

Notes and References

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2. Hong. Joung-Woo. Hendrix. David A.. Levine. Michael S.. 2008-09-05. Shadow Enhancers as a Source of Evolutionary Novelty. Science. en. 321. 5894. 1314. 10.1126/science.1160631. 0036-8075. 4257485. 18772429. 2008Sci...321.1314H.
3. Barolo. Scott. 2012. Shadow enhancers: Frequently asked questions about distributed cis-regulatory information and enhancer redundancy. BioEssays. en. 34. 2. 135–141. 10.1002/bies.201100121. 1521-1878. 3517143. 22083793.
4. Cannavò. Enrico. Khoueiry. Pierre. Garfield. David A.. Geeleher. Paul. Zichner. Thomas. Gustafson. E. Hilary. Ciglar. Lucia. Korbel. Jan O.. Furlong. Eileen E.M.. Eileen Furlong. January 2016. Shadow Enhancers Are Pervasive Features of Developmental Regulatory Networks. Current Biology. 26. 1. 38–51. 10.1016/j.cub.2015.11.034. 0960-9822. 4712172. 26687625.
5. Osterwalder. Marco. Barozzi. Iros. Tissières. Virginie. Fukuda-Yuzawa. Yoko. Mannion. Brandon J.. Afzal. Sarah Y.. Lee. Elizabeth A.. Zhu. Yiwen. Plajzer-Frick. Ingrid. Pickle. Catherine S.. Kato. Momoe. February 2018. Enhancer redundancy provides phenotypic robustness in mammalian development. Nature. en. 554. 7691. 239–243. 10.1038/nature25461. 1476-4687. 5808607. 29420474. 2018Natur.554..239O.
6. Garnett. Aaron T.. Square. Tyler A.. Medeiros. Daniel M.. 2012-11-15. BMP, Wnt and FGF signals are integrated through evolutionarily conserved enhancers to achieve robust expression of Pax3 and Zic genes at the zebrafish neural plate border. Development. 139. 22. 4220–4231. 10.1242/dev.081497. 0950-1991. 4074300. 23034628.
7. 1999-12-01. Redundant Enhancers Mediate Transcriptional Repression of AGAMOUS by APETALA2. Developmental Biology. en. 216. 1. 260–264. 10.1006/dbio.1999.9504. 0012-1606. free. Bomblies. Kirsten. Dagenais. Nicole. Weigel. Detlef. 10588876.
8. Cheung. David. Ma. Jun. October 2015. Probing the impact of temperature on molecular events in a developmental system. Scientific Reports. en. 5. 1. 13124. 10.1038/srep13124. 2045-2322. 4541335. 26286011. 2015NatSR...513124C.
9. Chen. Jun. Nolte. Viola. Schlötterer. Christian. 2015-02-26. Gibson. Greg. Temperature Stress Mediates Decanalization and Dominance of Gene Expression in Drosophila melanogaster. PLOS Genetics. en. 11. 2. e1004883. 10.1371/journal.pgen.1004883. 1553-7404. 4342254. 25719753 . free .