Rationally subdividing the fly nervous system with versatile expression reagents

Abstract

The ability to image and manipulate specific cell populations in Drosophila enables the investigation of how neural circuits develop and coordinate appropriate motor behaviors. Gal4 lines give genetic access to many types of neurons, but the expression patterns of these reagents are often complex. Here, we present the generation and expression patterns of LexA lines based on the vesicular neurotransmitter transporters and Hox transcription factors. Intersections between these LexA lines and existing Gal4 collections provide a strategy for rationally subdividing complex expression patterns based on neurotransmitter or segmental identity.

Keywords:

• Vesicular neurotransmitter transporters
• Hox genes
• neural circuit mapping
• expression patterns
• homologous recombination
• P-element replacement
• Drosophila

Acknowledgements

Jon-Michael Knapp, Phuong Chung, Karen Hibbard, and Shingo Yoshikawa made significant and excellent technical contributions to this work. The author thanks Sean Eddy and Elena Rivas for analyzing the results of whole genome sequencing, members of the Janelia FlyCore for assistance with fly wrangling, and Gudrhun Irke and colleagues for immunohistochemistry on some of the knock-in expression patterns. Steffi Hampel made some of the attP insertion constructs, and Andrew Seeds made the LexA enhancer trap starting line. Chris Potter donated the GAL80 P-element enhancer trap line. Khashayar Mozaffari, UCSB, confirmed the complementation testing of the VNT lines. Stocks obtained from the Bloomington Drosophila Stock Center (NIH P40OD018537) were used in this study. Members of the Ganetzky lab, Simpson lab, and many members of the fly community provided feedback during the evolution of this project. Many of the reagents described here have already been widely distributed and we are grateful for feedback about their utility.

Disclosure statement

The authors report no declaration of interest.

Funding

This work was supported by Helen Hay Whitney Post-doctoral fellowship, a L’Oreal Women in Science award, and Howard Hughes Medical Institute funds to JHS as a Janelia Group Leader.

Dedication

My first constructs to target neurons based on the neurotransmitter they produce were designed and build when I was a post-doctoral fellow with Dr. Barry Ganetzky at the University of Wisconsin, Madison between 2001 and 2006. Ling Ling Ho and I injected them to make transgenic flies at the microscope near Barry’s fly pushing station. Much of what I know the art of genetics was learned by asking Barry casual questions while we were sitting back-to-back, and much of what I love about doing research science myself and appreciating what the animal and its mutant phenotypes can tell us follows Barry’s example. I also promise to always use the word ‘comprise’ very carefully. On the occasion of his retirement, I am glad to have the chance to say thanks.