ArticleZoological letters2021
D-Tryptophan enhances the reproductive organ-specific expression of the amino acid transporter homolog Dr-SLC38A9 involved in the sexual induction of planarian Dugesia ryukyuensis.
Article in Zoological letters, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers, 1 of them a synthesis that pooled it.
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Who cites it
4 citing papers in PubMed, 1 synthesis or guideline pooled it, 6 citations in OpenAlex.
- Biological function of d-tryptophan: a bibliometric analysis and review.Frontiers in microbiology · 2024Pooled it
- Identification of an innexin required for termination of the asexual state in planarian reproductive switching.PLoS genetics · 2025Article
- Article
- Gut microbiota-driven regulation of queen bee ovarian metabolism.Microbiology spectrum · 2023Article
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6 authors at 4 institutions in 1 country.
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Abstract
backgroundMany animals switch between asexual and sexual reproduction in nature. We previously established a system for the sexual induction of planarian Dugesia ryukyuensis by feeding asexual planarians with minced sexual planarians. We identified DL-tryptophan (Trp) as one of the sex-inducing substances. DL-Trp can induce ovarian development, the first and essential step of sexual induction. D-Trp must act as a principal bioactive compound in terms of ovarian development, because the ovary-inducing activity of D-Trp was 500 times more potent than that of L-Trp. However, how Trp controls sexual induction is still unknown.
resultsIn this study, qRT-PCR analyses suggested that the putative amino acid transporter gene Dr-SLC38A9 is highly expressed in sexual worms, especially in the yolk glands. In situ hybridization analyses showed that Dr-SLC38A9 is expressed in the ovarian primordia of asexual worms and in the mature ovaries, testes, and yolk glands of sexual worms. In addition, Dr-SLC38A9 RNA interference during sexual induction resulted in the suppression of the development of reproductive organs. These results suggest that Dr-SLC38A9 is involved in the development of these organs. Moreover, we demonstrated that the reproductive organ-specific expression of Dr-SLC38A9 is enhanced by the addition of D-Trp.
conclusionWe propose that D-Trp activates the expression of Dr-SLC38A9 to promote sexual induction in the planarian D. ryukyuensis.
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