title: Sericin Composition in the Silk of Antheraea yamamai.
abstract: The silks produced by caterpillars consist of fibroin proteins that form two core filaments, and sericin proteins that seal filaments into a fiber and conglutinate fibers in the cocoon. Sericin genes are well-known in Bombyx mori (Bombycidae) but have received little attention in other insects. This paper shows that Antheraea yamamai (Saturniidae) contains five sericin genes very different from the three sericin genes of B. mori. In spite of differences, all known sericins are characterized by short exons 1 and 2 (out of 3-12 exons), expression in the middle silk gland section, presence of repeats with high contents of Ser and charged amino acid residues, and secretion as a sticky silk component soluble in hot water. The B. mori sericins represent tentative phylogenetic lineages (I) BmSer1 and orthologs in Saturniidae, (II) BmSer2, and (III) BmSer3 and related sericins of Saturniidae and of the pyralid Galleria mellonella. The lineage (IV) seems to be limited to Saturniidae. Concerted evolution of the sericin genes was apparently associated with gene amplifications as well as gene loses. Differences in the silk fiber morphology indicate that the cocktail of sericins linking the filaments and coating the fiber is modified during spinning. Silks are composite biomaterials of conserved function in spite of great diversity of their composition.
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.|Faculty of Science, University of South Bohemia , Branišovská 1760, 370 05 České Budějovice, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Zurovec
authors.affiliation: National Institute of Agrobiological Sciences Tsukuba , Ibaraki 305-8634, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Yonemura
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kludkiewicz
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: František
authors.initials: F
authors.lastname: Sehnal
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.|Faculty of Science, University of South Bohemia , Branišovská 1760, 370 05 České Budějovice, Czech Republic.
authors.forename: Dalibor
authors.initials: D
authors.lastname: Kodrik
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: Ligia Cota
authors.initials: LC
authors.lastname: Vieira
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Kucerova
authors.affiliation: Institute of Molecular Genetics ASCR , Vídeňská 1083, 142 20 Praha 4, Czech Republic.
authors.forename: Hynek
authors.initials: H
authors.lastname: Strnad
authors.affiliation: Faculty of Science, University of South Bohemia , Branišovská 1760, 370 05 České Budějovice, Czech Republic.
authors.forename: Peter
authors.initials: P
authors.lastname: Konik
authors.affiliation: Entomological Institute, Biology Centre ASCR , Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Sehadova
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019476:Insect Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009036:Moths / Q000378:metabolism*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D047030:Sericins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D047011:Silk / Q000737:chemistry*
chemical_list: D019476:Insect Proteins; D047030:Sericins; D047011:Silk