PUBLICATION
Characterization of two novel ammonia transporters, Hiat1a and Hiat1b, in the teleost model system Danio rerio
- Authors
- Zhouyao, H., Zimmer, A.M., Fehsenfeld, S., Liebenstein, T., Richter, D.O., Begemann, G., Eck, P., Perry, S.F., Weihrauch, D.
- ID
- ZDB-PUB-220921-22
- Date
- 2022
- Source
- The Journal of experimental biology 225(20): (Journal)
- Registered Authors
- Begemann, Gerrit, Perry, Steve F.
- Keywords
- Excretion, In situ hybridization, Morpholino, SIET, Zebrafish larvae
- MeSH Terms
-
- Ammonia/metabolism
- Animals
- Cation Transport Proteins*/metabolism
- Larva/metabolism
- Methylamines/metabolism
- Morpholinos
- Nitrogen/metabolism
- Zebrafish*/genetics
- Zebrafish*/metabolism
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism
- PubMed
- 36124551 Full text @ J. Exp. Biol.
Citation
Zhouyao, H., Zimmer, A.M., Fehsenfeld, S., Liebenstein, T., Richter, D.O., Begemann, G., Eck, P., Perry, S.F., Weihrauch, D. (2022) Characterization of two novel ammonia transporters, Hiat1a and Hiat1b, in the teleost model system Danio rerio. The Journal of experimental biology. 225(20):.
Abstract
Ammonia excretion in fish excretory epithelia is a complex interplay of multiple membrane transport proteins and mechanisms. Using the model system of zebrafish (Danio rerio) larvae, here we identified three paralogues of a novel ammonia transporter, hippocampus abundant transcript 1 (DrHIAT1), found also in most vertebrates. When functionally expressed in Xenopus laevis oocytes, DrHiat1a and DrHiat1b promoted methylamine uptake in a competitive manner with ammonia. In situ hybridization experiments showed that both transporters were expressed as early as the 4-cell stage in zebrafish embryos and could be identified in most tissues four days post fertilization. Larvae experiencing morpholino-mediated knockdown of DrHiat1b exhibited significantly lower whole body ammonia excretion rates compared to control larvae. Markedly decreased site-specific total ammonia excretion of up to 85% was observed in both the pharyngeal region (site of developing gills) and the yolk sac (region shown to have the highest NH4+ flux). This study is the first to identify especially DrHiat1b as an important contributor to ammonia excretion in larval zebrafish. Being evolutionarily conserved, these proteins are likely involved in multiple other general ammonia-handling mechanisms, making them worthy candidates for future studies on nitrogen regulation in fishes and across the animal kingdom.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping