Current Affiliation Organization 【 display / non-display 】

Current Affiliation Organization 【 display / non-display 】

University 【 display / non-display 】

University 【 display / non-display 】

Graduate School 【 display / non-display 】

Graduate School 【 display / non-display 】

Academic degree 【 display / non-display 】

Academic degree 【 display / non-display 】

External Career 【 display / non-display 】

External Career 【 display / non-display 】

display all >>

Affiliated academic organizations 【 display / non-display 】

Affiliated academic organizations 【 display / non-display 】

display all >>

Research Interests 【 display / non-display 】

Research Interests 【 display / non-display 】

display all >>

Research Areas 【 display / non-display 】

Research Areas 【 display / non-display 】

display all >>

Research Theme 【 display / non-display 】

Research Theme 【 display / non-display 】

• Comparative morphology of integumentary structures in tunicate

• Algal symbiosis in marine invertebrates

• Tunic morphology and functions

• Ascidian-cyanobacteria symbiosis system

Published Papers 【 display / non-display 】

Published Papers 【 display / non-display 】

• Dynamic Physical Distortions of Butterfly Pupal Wings: Potential Mechanical Signals from Eyespot Organizers for Color Pattern Determination

  Yugo Nakazato, Euichi Hirose, Joji M. Otaki

  Biology ( MDPI AG )  15 ( 11 ) 856 - 856   2026.05

  Type of publication: Research paper (scientific journal)

  　View Summary

  Butterfly wing color patterns are determined in pupal wing tissues, in which the prospective eyespot focus functions as a developmental organizer. Here, we investigated the microscopic structures of pupal wing tissues containing an eyespot organizer in line with the physical distortion hypothesis. Histochemical staining revealed that the pupal cuticle and epidermis were wavy and thin at 6 h but smooth and thick at 12 h postpupation. The eyespot organizer was associated with the thickest cuticle layer, called the cuticle focal spot. Transmission election microscopy (TEM) revealed that the intervening space (IVS) between the cuticle layer and the cellular apical end was wide at 6 h but narrow at 12 h postpupation. The spatial relationship between cuticle thickness and IVS width was indicative of mechanical buckling of the region adjacent to the cuticle focal spot. Live in vivo imaging revealed that the IVS at and near the eyespot organizer trapped orange fluorescent protein (OFP) injected into hemolymph. Dynamic distortions of the pupal wing epidermis and cuticular surface were detected in live individuals over time. These results suggest that physical distortions of the wing tissue induced by differential cuticle synthesis and subsequent buckling may function as mechanical morphogenic signals from eyespot organizers.

  • Access this article

    DOI

• Pre-fertilization Egg Coat Dynamics in Phallusia philippinensis (Tunicata, Ascidiacea).

  Kana Hanazaki, Noburu Sensui, Keita Kinjo, Madoka Sano, Takumi T. Shito, Euichi Hirose, Takako Saito

  Developmental Biology ( Elsevier BV )  536   95 - 106   2026.05 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

  • Access this article

    DOI

• Diversity of Exumbrellar Surface in Jellyfish with Remarks on the Optical Property of a Microvillar Array

  Jun Nishikawa, Daisuke Sakai, Hiroshi Kakiuchida, Euichi Hirose

  Zoological Science ( Zoological Society of Japan )  43 ( 3 ) 288 - 299   2026.04 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

  • Access this article

    DOI

• Genomic and transcriptomic resources for the tropical ascidian Phallusia philippinensis

  Shunsuke O Miyasaka, Takumi T Shito, Noburu Sensui, Euichi Hirose, Kotaro Oka, Kohji Hotta

  G3: Genes, Genomes, Genetics ( Oxford University Press (OUP) )    2026.03 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

  　View Summary

  Abstract Due to remarkably stereotyped development and small numbers of cells, ascidian embryos are invaluable as models for investigating the principles of chordate development at single-cell resolution. Established model species of ascidians, such as Ciona spp. and Phallusia mammillata, are primarily distributed in temperate waters, and natural populations become scarce in the summer due to rising water temperatures. However, Phallusia philippinensis is a tropical/subtropical species that is closely related to P. mammillata and shares the feature of highly transparent embryos, which facilitates live imaging and optical analyses. Its accessibility in warmwater habitats makes P. philippinensis a promising alternative model for imaging-based analyses, particularly in tropical regions or during the summer. We present comprehensive genomic transcriptomic resources that have been resolved according to the developmental stage for P. philippinensis. The assembled genome spans 150.2 Mb and comprises 407 contigs with an N50 of 909 kb and a GC content of 42.0%. Transcriptomes from 5 organs and 9 distinct embryonic stages were used to construct a gene model, which revealed 20,928 genes with a high BUSCO completeness score of 88.6%. Functional annotations were assigned to 16,507 genes using the UniProt and RefSeq databases. We integrated these resources into a new constructed genomic browser, which can be used easily by all researchers. These new resources are immediately applicable to comparative developmental studies of gene expression and regulation in ascidian embryos and will comprehensively cover the off-season of reproduction for model ascidians.

  • Access this article

    DOI

• Gnathiid male adults attract female larvae but are ignored by male larvae

  Yuhei Ohtake, Euichi Hirose

  Plankton and Benthos Research ( The Plankton Society of Japan/The Japanese Association of Benthology )  21 ( 1 ) 1 - 6   2026.03 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

  • Access this article

    DOI

display all >>

Other Papers 【 display / non-display 】

Other Papers 【 display / non-display 】

• Innate immunity in the edible ascidian Halocynthia roretzi developing soft tunic syndrome

  柳田哲矢, 仲山慶, 澤田知夫, 本庄美穂, 村上祥子, 飯田貴次, 広瀬裕一, 北村真一

  日本寄生虫学会大会プログラム・抄録集   92nd   2023

   

  J-GLOBAL

• What are the benefits in the ascidian-Prochloron symbiosis?

  その他の著者

  Endocytobiosis and Cell Research ( その他の出版社 )  15   51 - 62   2004

   

• Colonial allorecognition, hemolytic rejection, and viviparity in botryllid ascidians.

  E. Hirose

  Zoological Science ( 日本動物学会 )    2003.03

   

• Recent advances in molecular biology on pigmentation of the medaka, Oryzias latipes.

  J. Matsumoto, H. Ono, and E. Hirose

  The Fish Biology Journal MEDAKA ( The Fish Biology Journal MEDAKA )    1996.11

   

• Allorecognition in compound ascidians.

  Y. Saito, E. Hirose, H. Watanabe

  International Journal of Developmental Biology ( International Journal of Developmental Biology )    1994.05

   

display all >>

Academic Awards 【 display / non-display 】

Academic Awards 【 display / non-display 】

• Zoological Science Award

  2016.11.17   Zoological Society of Japan   Fine structure of the integumentary cuticles and alimentary tissue of pycnophyid kinorhynchs Pycnophyes oshoroensis and Kinorhynchus yushini (Kinorhyncha, Homalorhagida)

  Winner: Euichi Hirose, Hiroshi Yamasaki

Grant-in-Aid for Scientific Research 【 display / non-display 】

Grant-in-Aid for Scientific Research 【 display / non-display 】

• Comprehensive analysis of optical properties and evolutionary and diversification processes in the body surface of gelatinous zooplankton

  Grant-in-Aid for Scientific Research(B)

  Project Year: 2023.04  -  2028.03 

  Direct: 11,300,000 (YEN)  Overheads: 14,690,000 (YEN)  Total: 3,390,000 (YEN)

• Comprehensive analysis of optical properties in the body surface of gelatinous zoolankton and their evolutionary and diversification processes

  Grant-in-Aid for Scientific Research(B)

  Project Year: 2023.04  -  2028.03 

  Direct: 11,300,000 (YEN)  Overheads: 14,690,000 (YEN)  Total: 3,390,000 (YEN)

• The pathogenic flagellate Azumiobodo hoyamushi versus host ascidian immune system

  Grant-in-Aid for Scientific Research(B)

  Project Year: 2023.04  -  2026.03 

  Direct: 14,000,000 (YEN)  Overheads: 18,200,000 (YEN)  Total: 4,200,000 (YEN)

• The pathogenic flagellate Azumiobodo hoyamushi versus host ascidian immune system

  Grant-in-Aid for Scientific Research(B)

  Project Year: 2023.04  -  2026.03 

  Direct: 14,000,000 (YEN)  Overheads: 18,200,000 (YEN)  Total: 4,200,000 (YEN)

• Does nano-structures on the body surface decrease adhesive/friction forces?

  Grant-in-Aid for Scientific Research(C)

  Project Year: 2021.04  -  2024.03 

  Direct: 3,200,000 (YEN)  Overheads: 4,160,000 (YEN)  Total: 960,000 (YEN)

display all >>

Other External funds 【 display / non-display 】

Other External funds 【 display / non-display 】

• Project Year: 2010  -  2010 

  Direct: 0 (YEN)  Overheads: 0 (YEN)  Total: 0 (YEN)

• Project Year: 2007  -  2007 

  Direct: 0 (YEN)  Overheads: 0 (YEN)  Total: 0 (YEN)

• Project Year: 1992  -  1992 

  Direct: 0 (YEN)  Overheads: 0 (YEN)  Total: 0 (YEN)

SDGs 【 display / non-display 】

SDGs 【 display / non-display 】

Social Activity 【 display / non-display 】

Social Activity 【 display / non-display 】

• 2023.09