What is Endoreduplication?
What is Endoreduplication?
Select an option to attempt
Correct Answer: Option A
Explanation
HAT (Hypoxanthine-Aminopterin-Thymidine) selection in hybridoma production: Aminopterin is a folate antagonist that blocks dihydrofolate reductase (DHFR), inhibiting the de novo nucleotide synthesis pathway (purines;). Cells must then rely entirely on the salvage pathway (HGPRT for purines; thymidine kinase for pyrimidines) using the supplied hypoxanthine and thymidine. Unfused myeloma cells lack HGPRT (a selection trait of the parental myeloma cell line) and CANNOT use the salvage pathway → they die. Unfused spleen B cells have HGPRT but are mortal → die after a few divisions. Only hybridomas (fused myeloma + B cell) have both immortality and HGPRT → survive in HAT.