Irving, Carol;
(1997)
Characterisation of the receptor tyrosine kinase, Sek-1, during vertebrate embryogenesis.
Doctoral thesis (Ph.D), UCL (University College London).
Preview |
Text
Characterisation_of_the_recept.pdf Download (14MB) | Preview |
Abstract
During segmentation of the vertebrate hindbrain expression of a number of genes is precisely restricted within the rhombomeres. One such gene is Sek-1, a member of the Eph subfamily of receptor tyrosine kinases, originally identified through its striking segmental expression pattern in both the rhombomeres and the presomitic mesoderm in the mouse. I raised antibodies against mouse Sek-1 protein that are specific for a protein of 110 KDa, and cross-react with a protein of identical size in chick, zebrafish and Xenopus. I used the anti-Sek antibodies to carry out a spatio-temporal analysis of the protein in comparison to the gene transcript. Cross-reactivity of the antibodies allowed a comparison of Sek-1 protein expression between species, revealing a high level of conservation of expression, but with some differences. Sek-1 RNA is detected in the presomitic mesoderm in two stripes immediately caudal to the latest somite formed, corresponding to rostral somitomeres. I found that Sek-1 protein is also expressed here, but expression persists in the newly formed somites, becoming apically localised in the epithelium. In the rhombomeres, Sek-1 protein and RNA expression domains arise in pre- r3 and pre-r5 in narrow stripes that broaden. Expression initially occurs in fuzzy domains that sharpen as the rhombomere boundaries form. I propose that the establishment and maintainance of the rhombomere segments may involve both a dynamic regulation of r3/r5 identity and the restriction of cell movement across rhombomere boundaries. I also carried out experiments to attempt to interfere with the function of Sek-1 in the hindbrain using transgenic approaches. I designed constructs for the ectopic expression of Sek-1 cDNA specifically in r4, and for the expression of a truncated form of Sek-1 in r3/5 in a dominant negative strategy to specifically inactivate Sek-1 in the hindbrain.
| Type: | Thesis (Doctoral) |
|---|---|
| Qualification: | Ph.D |
| Title: | Characterisation of the receptor tyrosine kinase, Sek-1, during vertebrate embryogenesis |
| Open access status: | An open access version is available from UCL Discovery |
| Language: | English |
| Additional information: | Thesis digitised by ProQuest. ProQuest thesis, added to during UCL |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10101148 |
Archive Staff Only
 |
View Item |
