A zinc-finger fusion protein refines Gal4-defined neural circuits

Abstract

The analysis of behavior requires that the underlying neuronal circuits are identified and genetically isolated. In several major model species—most notably Drosophila—neurogeneticists identify and isolate neural circuits with a binary heterologous expression-control system: Gal4–UASG. One limitation of Gal4–UASG is that expression patterns are often too broad to map circuits precisely. To help refine the range of Gal4 lines, we developed an intersectional genetic AND operator. Interoperable with Gal4, the new system’s key component is a fusion protein in which the DNA-binding domain of Gal4 has been replaced with a zinc finger domain with a different DNA-binding specificity. In combination with its cognate binding site (UASZ) the zinc-finger-replaced Gal4 (‘Zal1’) was functional as a standalone transcription factor. Zal1 transgenes also refined Gal4 expression ranges when combined with UASGZ, a hybrid upstream activation sequence. In this way, combining Gal4 and Zal1 drivers captured restricted cell sets compared with single drivers and improved genetic fidelity. This intersectional genetic AND operation presumably derives from the action of a heterodimeric transcription factor: Gal4-Zal1. Configurations of Zal1–UASZ and Zal1-Gal4-UASGZ are versatile tools for defining, refining, and manipulating targeted neural expression patterns with precision.Electronic supplementary materialThe online version of this article (10.1186/s13041-018-0390-7) contains supplementary material, which is available to authorized users.

Serotonergic control of feeding microstructure in Drosophila

“…We used flies expressing CsChrimson in the Trh-Gal4 line, representing almost 80% of serotonergic cells ( Alekseyenko et al, 2010 ; Raghu et al, 2018 ) ( Figure 2B ), and assayed them in two conditions–fed and food-deprived. Fed flies had access to food ad libitum and approached the food in a normal hunger state.…”

Synthesis and characterization of polymeric composites with Cascabela thevetia incorporated zinc nanoparticles: Food packaging applications

“…The short life cycle at normal room temperature and the ease of maintaining them in the lab has resulted in using Drosophila widely as an in vivo model. In addition, they also offer many transgenic tools to study gene regulations and other genetic effects 62,63 . The current study used wild‐type D. melanogaster flies to evaluate the novel ZnNP's toxic impact using survival climbing assays (Figure 7).…”

“…In addition, they also offer many transgenic tools to study gene regulations and other genetic effects. 62,63 The current study used wild-type D. melanogaster flies to evaluate the novel ZnNP's toxic impact using survival climbing assays (Figure 7).…”

Anatomy and Neural Pathways Modulating Distinct Locomotor Behaviors in Drosophila Larva

“…For example, one study has implicated visual opsins in proprioception [ 134 ] and another implicated the gustatory role of chemoreceptors in wing mediated odor detection [ 135 ], indicating that multimodal cue-induced sensory behaviors may be regulated at multiple layers. Others have used refined intersectional genetic tools such as split-Gal4 [ 136 ] or zinc finger-based intersection methods [ 137 ], trans-synaptic labelling methods, activity depended GRASP and imaging methods for dissection of neural circuits [ 116 , 138 , 139 , 140 , 141 ], and fast optogenetic actuators such as crimson [ 18 ] and GtACR1 [ 17 ], to study the necessity and sufficiency of a single neuron to single muscle pathway. By these approaches, understanding which neural pathways control specific parts of behaviors may not be far away.…”