HOX gene

Jones, F. S., Prediger, E. A., Bittner, D. A., DeRobertis, E. M., and Edelman, G. M. (1992b). Cell adhesion molecules as targets for Hox genes neural cell adhesion molecule promoter activity is modulated by cotransfection with Hox-2.5 and -2.4. Proc. Natl. Acad. Sci. USA 89 2086-2090. 

McMahon The subject hasn t arisen in our discussion, but we should mention homeobox (Hox) genes here. The current model of the profound role that these play is that they regulate sizes and structures. It is a powerful argument that the reason that our radius and ulna are a different size from our humerus is because of the Hox genes that somehow intrinsically control that system. In the absence of the Hox genes, what you get is the formation of the initial anlages but a failure of growth of those structures. 

Raff Is the connection between the Hox genes and the cell cycle still a mystery ... 

McMahon Actually, I think it is even worse than that. The connection between the Hox genes and what is going on in those primordia in any sense is unknown. I can t understand why this is the case the model, formulated by Denis Dubole, has been out there for some time. It is a persuasive model, but we don t even know whether the Hox genes are actually expressed within the cartilage cells and have cell autonomous effects, or whether they are outside the cartilage. 

Rehner In bithorax mutants the haltere disc grows just like a wing disc it is an obvious example where a Hox gene determines organ size. The mechanism is not understood. 

Greer, J. M., Puetz, J., Thomas, K. R. and Capecchi, M. R. (2000), Maintenance of functional equivalence during paralogous Hox gene evolution , Nature (London), 403, 661 -665. 

In Drosophila, the two-MBT-repeat protein Scm is a core component in the PRC1 complex, and is essential for the repression of Hox genes [53]. 

J. Dubrulle, M. J. McGrew, and O. Pourquie, FGF signaling controls somite boundary position and regulates segmentation clock control of spatiotemporal Hox gene activation. Cell 106,219— 232 (2001). 

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