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. 2012;8(3):e1002591.
doi: 10.1371/journal.pgen.1002591. Epub 2012 Mar 8.

The silkworm coming of age--early

René Feyereisen  1 , Marek Jindra
Affiliations

The silkworm coming of age--early

René Feyereisen et al. PLoS Genet. 2012.
No abstract available

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Development of the silkworm without juvenile hormones (JHs).
Maintenance of larval characters before the larval-pupal and pupal-adult molts is the classical status quo role of JH. This JH effect is carried out through its receptor Met and the transcription factor Kr-h1. The mod mutants studied by Daimon et al. lack a P450 enzyme (epoxidase) and cannot make functional JH, yet they do not enter metamorphosis until after two larval molts, producing precocious pupae instead of the normal fourth larval instar. This unexpected result suggests that the early larval instars might be insensitive to the lack of JH. Illustration: Martina Hajduskova.
See this image and copyright information in PMC

References

    1. Goodman WG, Cusson M. The juvenile hormones. In: Gilbert LI, editor. Insect endocrinology. Amsterdam: Elsevier; 2012. pp. 310–365.
    1. Nijhout HF. A threshold size for metamorphosis in the tobacco hornworm, Manduca sexta (L.). Biological Bulletin. 1975;149:214–225. - PubMed
    1. Callier V, Nijhout HF. Control of body size by oxygen supply reveals size-dependent and size-independent mechanisms of molting and metamorphosis. Proc Natl Acad Sci U S A. 2011;108:14664–14669. - PMC - PubMed
    1. Daimon T, Kozaki T, Niwa R, Kobayashi I, Furuta K, et al. Precocious metamorphosis in the juvenile hormone-deficient mutant of the silkworm, Bombyx mori. PLoS Genet. 2012;8:e1002486. doi: 10.1371/journal.pgen.1002486. - DOI - PMC - PubMed
    1. Helvig C, Koener JF, Unnithan GC, Feyereisen R. CYP15A1, the cytochrome P450 that catalyzes epoxidation of methyl farnesoate to Juvenile Hormone III in cockroach corpora allata. Proc Natl Acad Sci U S A. 2004;101:4024–4029. - PMC - PubMed