Tadr Is an axonal histidine transporter required for visual neurotransmission in Drosophila

  1. Yongchao Han
  2. Lei Peng
  3. Tao Wang  Is a corresponding author
  1. National Institute of Biological Sciences, Beijing, China

Abstract

Neurotransmitters are generated by de novo synthesis and are essential for sustained, high-frequency synaptic transmission. Histamine, a monoamine neurotransmitter, is synthesized through decarboxylation of histidine by Histidine decarboxylase (Hdc). However, little is known about how histidine is presented to Hdc as a precursor. Here, we identified a specific histidine transporter, TADR (Torn And Diminished Rhabdomeres), which is required for visual transmission in Drosophila. Both TADR and Hdc localized to neuronal terminals, and mutations in tadr reduced levels of histamine, thus disrupting visual synaptic transmission and phototaxis behavior. These results demonstrate that a specific amino acid transporter provides precursors for monoamine neurotransmitters, providing the first genetic evidence that a histidine amino acid transporter plays a critical role in synaptic transmission. These results suggest that TADR-dependent local de novo synthesis of histamine is required for synaptic transmission.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file.

Article and author information

Author details

  1. Yongchao Han

    National Institute of Biological Sciences, Beijing, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1965-0161
  2. Lei Peng

    National Institute of Biological Sciences, Beijing, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Tao Wang

    National Institute of Biological Sciences, Beijing, Beijing, China
    For correspondence
    wangtao1006@nibs.ac.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2395-3483

Funding

National Natural Science Foundation of China (81870693)

  • Tao Wang

National Natural Science Foundation of China (81670891)

  • Tao Wang

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: The animal work for generating the antisera was conducted following the National Guidelines for Housing and Care of Laboratory Animals in China, and performed in accordance with institutional regulations after approval by the IACUC at NIBS (Reference# NIBS2016R0001).

Copyright

© 2022, Han et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Yongchao Han
  2. Lei Peng
  3. Tao Wang
(2022)
Tadr Is an axonal histidine transporter required for visual neurotransmission in Drosophila
eLife 11:e75821.
https://doi.org/10.7554/eLife.75821

Share this article

https://doi.org/10.7554/eLife.75821

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