Date of Award
Fall 12-2014
Degree Type
Masters Thesis
Degree Name
Master of Science (MS)
Department
Biological Sciences
Committee Chair
Sandra Leal
Committee Chair Department
Biological Sciences
Committee Member 2
Hao Xu
Committee Member 2 Department
Biological Sciences
Committee Member 3
Janis O'Donnell
Abstract
From a genetic and allelic modifier screen, we report that the Drosophila melanogaster T-box transcription factor midline (mid), a homolog to the human TBX20 gene, interacts with dFOXO within the insulin receptor (InR) and the c-Jun-N-terminal kinase (JNK) signaling pathways to regulate interommatidial bristle (IOB) formation. Previous studies have identified mid’s role in cell fate specification of sensory organ precursor cells in conjunction with the Notch-Delta signaling pathway (Das et al., 2013). The Notch, InR, and JNK signaling pathways regulate dFOXO activity under conditions of stress. Thus, we determined the effects of oxidative stress and metabolic stress by exposing mid-RNAi flies to paraquat and starvation conditions, respectively. We found that oxidative stress suppressed the mid-RNAi phenotype while starvation had no significant effect. We next assayed Mid and H15, a paralog of Mid, via Western blot analysis and report that Mid exhibits a nucleocytoplasmic distribution pattern that is altered within the mid-RNAi mutant while H15 was found exclusively within the cytoplasmic fraction. This opens the possibility that Mid and/or H15 may regulate cytoplasmic targets upstream of dFOXO. The evidence suggests that Mid utilizes the InR, JNK, and Notch signaling pathways to regulate cell fate specification, differentiation, and survival during third instar larval development.
Copyright
2014, Qichuan Chen
Recommended Citation
Chen, Qichuan, "The Drosophila T-box Transcription Factor Midline Functions within the Insulin/AKT and c-Jun-N-terminal Kinase Signaling Pathways to Regulate Interomatidial Bristle Formation and Cell Survival" (2014). Master's Theses. 76.
https://aquila.usm.edu/masters_theses/76