571V Poster Online - Virtual Posters
Wednesday April 06, 4:00 PM - 7:00 PM

Authors:
Risa Takenaka ^1,2; Harmit Malik ^1,3

Affiliations:
1) Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA; 2) Graduate Program in Molecular and Cellular Biology, University of Washington, Seattle, WA; 3) Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA

Keywords:
n. other (histone expression); a. core promoters and general transcription factors

Eukaryotic genomes are packaged into chromatin, which is composed of histone-containing nucleosomes. Insufficient histone levels result in poor packaging and promiscuous transcription, whereas excess histone levels impede transcription and other essential cellular processes. Therefore, an optimal histone-to-genome ratio is critical to maintain cellular functions and organismal fitness. In Drosophila, the abnormal oocyte (abo) gene encodes a repressor of core histones. abo is a maternal-effect lethal gene first isolated by Larry Sandler. abo homozygous-mutant females produce fewer offspring relative to their heterozygous sisters. This defect can be attributed to an overproduction of histones, which disrupt the maternal-to-zygotic transition during embryogenesis. Despite abo’s important function in histone regulation, abo-mutant adults show no other morphological phenotypes. Therefore, the Drosophila abo is an intriguing model for studying novel aspects of tissue-specific vulnerabilities to histone overexpression. To this end, I have generated a precise, CRISPR/Cas9-mediated knockout of abo flies to accurately interpret the in-vivo consequences of histone overexpression. Using this abo-knockout fly, I will measure transcriptomic consequences of histone overexpression to potentially explain why different tissues and developmental stages might vary in their responses to histone overexpression.