The role of Filippi’s glands in the silk moths cocoon construction

0549900 - BC 2022 RIV CH eng J - Journal Article
Sehadová, Hana - Závodská, Radka - Rouhová, Lenka - Žurovec, Michal - Šauman, Ivo
The role of Filippi’s glands in the silk moths cocoon construction.
International Journal of Molecular Sciences. Roč. 22, č. 24 (2021), č. článku 13523. E-ISSN 1422-0067
R&D Projects: GA MŠMT(CZ) EF16_013/0001775; GA MŠMT(CZ) LM2018129
Grant - others:Interreg Bayern Tschechische Republik(AT) Ziel ETZ2021-2022, no. 331
Institutional support: RVO:60077344
Keywords : Filippi’s glands * Saturniidae * cocoon structure
OECD category: Entomology
Impact factor: 6.208, year: 2021
Method of publishing: Open access
https://www.mdpi.com/1422-0067/22/24/13523/pdf

Filippi’s glands (FGs), formerly also called Lyonet’s glands, are accessory secretory structures of the labial (silk) glands of lepidopteran caterpillars, which were implicated to play an important role in the maturation of the silk material and the construction of the cocoon. In our previous study, we have identified several species of giant silk moths that completely lack the FGs. Interestingly, the absence of FGs in these species correlates with the construction of a loose cocoon architecture. We investigated the functions of FGs by their surgical extirpation in the last instar larvae of the silkworm, Bombyx mori. We found that the absence of FGs altered the structure of the resulting cocoon, in which the different layers of silk were separated. In further experiments, we found no effects of the absence of FGs on larval cocoon formation behavior or on changes in cocoon mass or lipid content. Differential proteomic analysis revealed no significant contribution of structural proteins from FGs to silk cocoon material, but we identified several low abundance proteins that may play a role in posttranslational modifications of some silk proteins. Proteomic analysis also revealed a difference in phosphorylation of the N-terminal sequence of fibroin-heavy chain molecule. Thus, FGs appear to affect silk stickiness during spinning by regulating posttranslational modifications. This could also explain the link that exists between the absence of these glands and the formation of loose cocoons in some giant silk moth species.
Permanent Link: http://hdl.handle.net/11104/0327017