ɪɴᴠᴇꜱᴛɪɢᴀᴛɪɴɢ ᴛʜᴇ ʀᴏʟᴇ ᴏꜰ ɪɴᴛʀᴏɴꜱ ɪɴ ꜱᴀᴄᴄʜᴀʀᴏᴍʏᴄᴇꜱ ᴄᴇʀᴇᴠɪꜱɪᴀᴇ

Candidate: Nour-Zaynab Bazzi
Supervisor: Dr. Mojca Mattiazzi Usaj

ABSTRACT

Endocytosis is a highly conserved cellular process required to internalize external nutrients and membrane components into the cell. A genome-wide live-cell real-time fluorescence microscopy screen was previously done to identify genetic factors required for proper spatial and temporal dynamics of early endocytic events using budding yeast as a model organism. This screen identified a few hundred genes involved in different bioprocesses for their potential to affect endocytic patch formation at the plasma membrane. Among these, genes involved in splicing constituted the most enriched bioprocess. Splicing is a process that removes non-protein coding nucleotide sequences called introns from nascent mRNA strands. Considering the energetic burden that introns pose on the host cell, it becomes interesting to think about their biological function in organisms like budding yeast, where alternative splicing is rare. Existing studies demonstrate that introns may regulate the cellular response to starvation by causing inefficient splicing. In this thesis, I investigated the effect of intron disruption on the dynamics of endocytic patch formation in both control and glucose starvation conditions. I further investigated the broader impact of intron disruption on cell growth and survival. My findings suggest that depending on their unique characteristics, different introns vary in their effects on distinct phenotypes, which could be influenced by nutrient availability.