Nhu Phan
University of Gothenburg, Gothenburg, Sweden
Title: Lipid imaging of invertebrate model systems by secondary ion mass spectrometry
Biography
Biography: Nhu Phan
Abstract
Drosophila melanogaster and C. elegans (flies and worms, respectively) are common biological model systems, which have relatively simple anatomy and behavior but possess highly conserved molecular and cellular processes compared to humans. We have applied time of flight secondary ion mass spectrometry (ToF-SIMS) to study lipid structural effects of stimulant drug methylphenidate on the fly brain, and to investigate the 3D chemical anatomy of C. elegans. Different distributions of various biomolecules, particularly fatty acids, eye pigment, diacylglycerides, phospholipids have been found across the fly brain. Lipid structures, particularly diacylglycerides (DAG), phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositiol (PI), are shown to dramatically alter following the administration of methylphenidate. For C. elegans, the entire worm and worm sections were imaged using 3 dimensional (3D) and 2 dimensional (2D) approaches, respectively. Significant changes in the chemical distribution were observed along the depth of the worm. In addition, correlation between 2D and 3D ion images showed different molecular structures across the worm, possible localization of the nerve ring, the cuticle, and the fluid containing space inside the worm. In addtion, we successfully used tandem MS on ToF-SIMS with a high energy 40 keV Ar4000+ gas cluster primary ion beam (GCIB) to elucidate the structures of molecular lipids in the fly brain and the worm. ToF-SIMS imaging shows great potential to elucidate chemical distributions in small invertebrate systems in relation to endogenous and exogenous effects.