About the Authors

Yoshihiko Kuwana

Affiliation Silk Materials Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan

Hideki Sezutsu

Affiliation Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan

Ken-ichi Nakajima

Affiliation Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan

Yasushi Tamada

Affiliations Silk Materials Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan, Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano, Japan

Katsura Kojima

kojikei@affrc.go.jp

Affiliation Silk Materials Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: YK HS YT KK. Performed the experiments: YK HS KN YT KK. Analyzed the data: YK HS KN YT KK. Contributed reagents/materials/analysis tools: YK HS KN YT KK. Wrote the paper: YK HS KN YT KK.