TAIL DEVELOPMENT: Tail termination
Hox genes. These delineate tail regions and determine the number of somites that are formed for each species. The Hox genes that are expressed right at the end of the tail act to terminate tail growth. Thus, over-express all Hox13 paralogs (that is, each gene in the A, B, C and D cluster) at the posterior end of the mouse or chick embryo and the tail is terminated prematurely. Against this, knock out these genes, and tail structures grow bigger and there are more of them. The tail elongates. There are several reasons for this knockout causing a longer tail - apoptosis in the PSM is interfered with, as are other signaling cascades which limit tail growth. Conversely, with the Hox13 paralogs in place, the termination signals are maintained as is apoptosis in the PSM.
The authors sum up this long and complex section of the paper as follows:-
Hox13 paralogs. The vertebrae are bigger and of a slightly different shape. And two extra vertebrae (asterisks) form in the tail. Because the Hox13
Originally posted by link at OP
Originally posted by link at OP
The authors sum up this long and complex section of the paper as follows:-
Originally posted by link at OP
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