Date of Award
2009
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Biology
Abstract
Identification of genes that are possibly stimulators or inhibitors in limb regeneration in vertebrates is important in understanding the regeneration mechanism and the cause of regeneration failure in non-regenerative structures. It is proposed that the development of the immune system of adult anurans modifies the capacity of limb regeneration. This modulation is mainly due to the participation of variety of immune cells in the response to inflammation caused by amputation. The influence of cytokines and their modulators including S uppressors o f C ytokine S ignaling (SOCS) proteins is critical in determining the nature of tissue response to injury and the degree of tolerance of new cells forming regenerating structures. The South African clawed frog, Xenopus laevis , has a complete limb regenerative capacity at early developmental stages that is gradually decreased in the adult as the immune system matures. This study reports a successful isolation of a full-length X. laevis SOCS1 cDNA for the first time, and a full-length SOCS3 cDNA. An analysis of the temporal expression indicated an expression for both genes at the stage when the formation of a limb bud starts. The comparison of the expression of SOCS1 and SOCS3 in regenerative blastemas and non-regenerative pseudoblastemas showed an induction of both genes within one-day post amputation with a higher expression of SOCS3. The expression was maintained though five days with a higher expression in non-regenerative pseudoblastemas. Using whole mount in situ hybridization, it was determined that the induced expression was in mesodermal cells. Data of amputated limb cultures postulated that the induced expression is a local response. Beryllium, which is known to repress regenerative capacity, showed a suppressed expression of the patterning gene, Shh, in correlation with an induction of SOCS1 and SOCS3 in beryllium-treated blastema. In conclusion, this study addresses the role of SOCS1 and SOCS3 in the limb regeneration.
Recommended Citation
Abu-Niaaj, Lubna Fawzi, "Analysis Of The Expression Of Selected Suppressors Of Cytokine Signaling, Socs1 And Socs3, Genes In Response To Limb Amputation In Xenopus Laevis" (2009). All-Inclusive List of Electronic Theses and Dissertations. 1864.
https://scholars.indianastate.edu/etds/1864