Developmental genes

The best examples of pleiotropy have been provided by developmental biologists. Two examples illustrate the pleiotropic action of developmental genes. Sonic hedgehog participates in the formation of the different cell types that form the neural tube, in limb development and in somitogenesis, a process by which mesodermic cells aggregate to form bones and muscles. 

This pleiotropic action of developmental genes is easily explained by the fact that the proteins encoded by these genes are components of pathways and networks, which have been repeatedly used during evolution for the construction of organisms. 

In general, the differences in expression and structure of HI variants strongly suggests that variants of linker histones have important roles in chromatin architecture, and might be essential players in the epigenetic control of developmental gene expression. Future studies will be necessary to identify factors that target, modify, and mobilize different linker histones. 

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Sandelin, A., Bailey, P., Bruce, S., et al. (2004) Arrays of ultraconserved non-coding regions span the loci of key developmental genes in vertebrate genomes. BMC Genomics. 5,99. 

McCarty, D.R. et al., The Viviparous-1 developmental gene of maize encodes a novel transcriptional activator. Cell, 66, 895, 1991. 

Schoppmeier, M. and Damen, W.G. (2001) Double-stranded RNA interference in the spider Cupiennius salei the role of Distal-less is evolutionarily conserved in arthropod appendage formation. Developmental Genes and Evolution 21 1, 76-82. 

Friedrich, G. and Soriano, P. (1991) Promoter traps in embryonic stem cells a genetic screen to identify and mutate developmental genes in mice. Genes Dev. 5, 1513-1523. 

The makeup of an insect nose peripheral structures and developmental genes... 

M. Singler and D. Kaiser (1995). Ectopic production of guanosine penta- and tetraphosphate can initiate early developmental gene expression in Myxococcus xanthus. Genes Dev., 9, 1633-1644. 

The Drosophila characteristics that allowed the discovery of the first developmental genes are the so-called homeotic mutations which... 

CapeUo E, Voskuhl RR, McFarltmd HE, Refine CS (1997) Multiple sclerosis re-expression of a developmental gene in chronic lesions correlates with lemyeUnation. Ann Neurol 41 797-805... 

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Boulay, J.L., Dennefeld, C., and Alberga, A. (1987). The Drosophila developmental gene snail encodes a protein with nucleic acid binding fingers. Nature 350 395-398. 

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