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Published on: September 13, 2022
DNA interference-mediated screening of maternal factors in the chordate Oikopleura dioica
Tatsuya Omotezako1, Masaki Matsuo1, Takeshi A Onuma1
1Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
Abstract:
The maternal contribution to the oocyte cytoplasm plays an important role during embryogenesis because it is involved in early cell fate specification and embryonic axis establishment. However, screening projects targeting maternal factors have only been conducted in a limited number of animal models, such as nematodes, fruit flies, and zebrafish, while few maternal genes have been analysed because of difficulties encountered in inhibiting gene products already expressed in the ovaries. Therefore, simple and efficient methods for large-scale maternal screening are necessary. The appendicularian Oikopleura dioica is a planktonic tunicate member of the chordates. Gonadal microinjection and a novel gene knockdown method, DNA interference (DNAi), have been developed for use in this animal with the aim of inhibiting gene functions during oogenesis within the gonad. In this study, we adapted these methods for large-scale maternal factor screening, and observed malformation phenotypes related to some maternal factors. Approximately 2000 (56.9%) ovary-enriched gene products were screened, of which the knockdown of seven encoding genes resulted in various abnormalities during embryonic development. Most of these were related to microtubules and cell adhesion-related proteins. We conclude that DNAi is a potentially powerful screening tool for the identification of novel maternal factors in chordates.
Insights
Researchers screened maternal factors in Oikopleura dioica using DNA interference (DNAi) to identify genes crucial for embryonic development. This method revealed novel maternal genes involved in microtubules and cell adhesion, highlighting DNAi
Area of Science:
- Developmental Biology
- Genetics
- Chordate Embryogenesis
Background:
- Maternal factors in oocyte cytoplasm are vital for early embryogenesis, influencing cell fate and axis establishment.
- Previous screening for maternal factors has been limited to a few model organisms due to challenges in inhibiting pre-expressed genes.
- Efficient large-scale screening methods for maternal factors are needed.
Purpose of the Study:
- To adapt and utilize DNA interference (DNAi) for large-scale maternal factor screening in the chordate Oikopleura dioica.
- To identify novel maternal genes and their roles in embryonic development within a chordate model.
Main Methods:
- Utilized Oikopleura dioica, a planktonic tunicate chordate.
- Employed gonadal microinjection and a novel DNA interference (DNAi) gene knockdown technique.
- Screened approximately 2000 ovary-enriched gene products for developmental abnormalities.
Main Results:
- Successful adaptation of DNAi for large-scale maternal screening in Oikopleura dioica.
- Identified seven genes whose knockdown resulted in embryonic developmental abnormalities.
- Discovered that many identified maternal factors are associated with microtubules and cell adhesion.
Conclusions:
- DNA interference (DNAi) is a powerful and efficient tool for screening maternal factors in chordates.
- The study identified novel maternal genes critical for embryonic development, particularly those involved in cytoskeletal organization and cell-cell interactions.
- Oikopleura dioica serves as a valuable model for studying maternal effects in chordate embryogenesis.
