Embedding Adult Drosophila Heads in Paraffin: Preparing Tissue for Histology

Abstract

Source: Sunderhaus, E. R., Kretzschmar, D. Mass Histology to Quantify Neurodegeneration in Drosophila .J. Vis. Exp. (2016).

This video describes how to embed Drosophila heads in paraffin using the collar method, a technique that prepares fly heads for serial sectioning. Paraffin sections are used for histological examinations of the brain's anatomy and for the assessment of neurodegeneration. The featured protocol demonstrates how multiple flies can be processed in one preparation, thereby increasing time-efficiency and minimizing experimental artifacts.

Protocol

This protocol is an excerpt from Sunderhaus and Kretzschmar, Mass Histology to Quantify Neurodegeneration in Drosophila, J. Vis. Exp. (2016). 1. Fixing the Head on Collars and Embedding in Paraffin NOTE: All of the steps in the fixation process should be done in a fume hood. Methylbenzoate, while not posing a health risk, has a highly distinct odor, whic…

Representative Results

Figure 1: Paraffin Serial Sections. A) Using the collar method, experimental and control flies can be processed as one sample by threading them onto one collar. Eyeless sine oculis flies are inserted for orientation (arrows). B) Schematic showing the orientation of the fly heads in the collar. C) In this image, sections from different fly heads are oriented …

Materials

Collar	Genesee Scientific	TS 48-100	We are using custom made collars that are made from one piece of metal instead of layers as the ones by Genesee.
Rubber ice cube tray for embedding	Household store		The size can be made-to-fit by glueing in additional walls
Crystallizing dish	Fisher Scientific Company	08-762-3
Ether	Fisher Scientific Company	E138-1
Ethanol	Decon Laboratories Inc.	2701
Choloroform	Fisher Scientific Company	C298-500
Glacial Acetic Acid	Fisher Scientific Company	A38-212
Methylbenzoate	Fisher Scientific Company	M205-500	Distinct Odor – Use in fume hood!
Low Melting Point Paraffin Wax	Fisher Scientific Company	T565	Make sure to keep extra melted in a 65 °C waterbath