EXPRESSION OF TSF 1 ( TRANSFERRIN 1 ) AND TSF 2 ( TRANSFERRIN 2) IN DROSOPHILA MELANOGASTER EXPOSED TO X-RAYS AND THERAPEUTIC RADIATION

Ionizing radiation is known to trigger a wide range of genetic and epigenetic modifications that disrupt cellular equilibrium and activate stress response pathways. This study aimed to evaluate the transcriptional behavior of two iron metabolism–associated genes, Transferrin 1 (TSF1) and Transferrin 2 (TSF2), in Drosophila melanogaster subjected to X-ray and low-dose CT room radiation. These transferrin genes are central to maintaining iron balance and epithelial stability, making them valuable candidates for assessing molecular alterations induced by radiation exposure. Adult flies were exposed to radiation for 7 and 14 days, after which total RNA was extracted and analyzed using semi- quantitative RT-PCR, with GAPDH serving as an internal control for normalization. The results revealed a consistent and significant elevation in TSF1 expression under both radiation types. For instance, expression levels increased from control values of 67.77 ± 1.84 to 80.14 ± 1.00 at day 7 and further to 85.97 ± 1.43 by day 14 under X-ray exposure. A similar trend was observed in CT room–exposed flies, where expression rose to 80.20 ± 0.72 at day 7 and 86.28 ± 1.85 at day 14. This persistent upregulation suggests that TSF1 plays a protective role by enhancing iron sequestration and transport, thereby reducing the generation of reactive oxygen species (ROS) and limiting oxidative injury. In contrast, TSF2 demonstrated a biphasic expression profile. An initial increase was recorded at 7 days post-exposure (72.23 ± 2.39 following X-rays), but expression declined sharply at 14 days, particularly in CT-exposed flies (57.76 ± 1.94) relative to control levels (61.96 ± 1.14). In Conclusion, This pattern indicates an early, short-lived adaptive response followed by suppression, possibly reflecting tissue vulnerability and compromised epithelial barrier function under chronic radiation stress.