Lepidopteran silk is a complex assembly of proteins produced by a pair of highly specialized labial glands called silk glands. Silk composition has been examined only in a handful of species. Here we report on the analysis of silk gland-specific transcriptomes from three developmental stages of the greater wax moth, Galleria mellonella, combined with proteomics, Edman microsequencing and northern blot analysis. In addition to the genes known earlier, we identified twenty seven candidate cDNAs predicted to encode secretory proteins, which may represent novel silk components. Eight were verified by proteomic analysis or microsequencing, and several others were confirmed by similarity with known silk genes and their expression patterns. Our results revealed that most candidates encode abundant secreted proteins produced by middle silk glands including ten sericins, two seroins, one or more mucins, and several sequences without apparent similarity to known proteins. We did not detect any novel PSG-specific protein, confirming that there are only three fibroin subunits. Our data not only show that the number of sericin genes in the greater wax moth is higher than in other species thus far examined, but also the total content of soluble proteins in silk is twice as high in G. mellonella than in B. mori or A. yamamai. Our data will serve as a foundation for future identification and evolutionary analysis of silk proteins in the Lepidoptera.
- MeSH
- fylogeneze MeSH
- glykoproteiny chemie genetika metabolismus MeSH
- hedvábí genetika metabolismus MeSH
- hmyzí proteiny chemie genetika metabolismus MeSH
- larva genetika růst a vývoj metabolismus MeSH
- muciny chemie genetika metabolismus MeSH
- můry genetika růst a vývoj metabolismus MeSH
- proteom * MeSH
- sekvence aminokyselin MeSH
- sekvence nukleotidů MeSH
- sekvenční seřazení MeSH
- sericiny chemie genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Adipokinetic hormones (Akhs) are small peptides (8-10 amino acid [aa] residues long) found in insects that regulate metabolic responses to stress by stimulating catabolic reactions and mobilizing energy stores. We employed Transcription activator-like effector nuclease (TALEN) mutagenesis and isolated an Akh(1) mutant carrying a small deletion in the gene that resulted in a truncated peptide; the second aa (Leu) was missing from the functional octapeptide. This null Dmel/Akh mutant is suitable to study Akh function without any effect on the C-terminal associated peptide encoded by the same gene. The mutant flies were fully viable and compared to the control flies, had significantly low levels of hemolymph saccharides including trehalose and were resistant to starvation. These characteristics are similar to those obtained from the flies carrying targeted ablation of Akh-expressing neurons (reported earlier). We also found that the Akh(1) mutants are slightly heavy and had a slow metabolic rate. Furthermore, we showed that the ectopic expression of Dmel∖Akh reverses the Akh(1) phenotype and restores the wild-type characteristics. Our results confirmed that Akh is an important regulator of metabolic homeostasis in Drosophila.
- MeSH
- Drosophila melanogaster genetika metabolismus MeSH
- energetický metabolismus MeSH
- hemolymfa chemie MeSH
- hmyzí hormony genetika metabolismus MeSH
- homeostáza MeSH
- kyselina pyrrolidonkarboxylová analogy a deriváty metabolismus MeSH
- molekulární sekvence - údaje MeSH
- mutageneze MeSH
- oligopeptidy genetika metabolismus MeSH
- potravinová deprivace MeSH
- sekvence aminokyselin MeSH
- sekvence nukleotidů MeSH
- tělesná hmotnost MeSH
- trehalosa metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH