How stage identity is established in insects: the role of the Metamorphic Gene Network

Chafino, Silvia; Franch-Marro, Xavier

doi:10.1016/j.cois.2020.10.002

Cited by 40 publications

(44 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Degeneration of the larval muscles was observed in the "propupal" and "pupal" stages of Frankliniella fusca and Haplothrips verbasci [35]. As stated above, the overall developmental expression profiles of Kr-h1 and br in thrips (Fig 3B) are similar to that of holometabolous species rather than that of hemimetabolous species [7,30]: the expression of br is maintained in the nymphal stage in Hemimetabola, whereas br is specifically expressed at larva-pupa transition of Holometabola and thrips. In this study, we showed that the transcript level of E93 increased as those of Kr-h1 and br decreased in the "propupal" stage of thrips (Fig 3B).…”

Section: Possible Regulatory Mechanism Of E93 Transcription In Thripssupporting

confidence: 53%

“…The regulatory mechanism of E93 transcription was first elucidated in B. germanica, T. castaneum, D. melanogaster, and B. mori [7,15,24,26,30]. E93 has also been characterized in other species including paraneopteran brown planthopper Nilaparvata lugens [33] and common bed bug Cimex lectularius [34].…”

Section: Possible Regulatory Mechanism Of E93 Transcription In Thripsmentioning

confidence: 99%

“…Recently, expression analyses of E93 revealed that the differential expression of E93 is involved in sexual dimorphic development in the strepsipteran Xenos vesparum [27] as well as in the mealybug Planococcus kraunhiae [28]. The regulatory interaction among Met, Kr-h1, and E93 is considered as the center of JH signaling, and called as 'Met-Kr-h1-E93 (MEKRE93) pathway' [7,29], or 'Metamorphic Gene Network' [26,30], which is thought to exist both in hemimetabolous and holometabolous species.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Characterization of E93 in neometabolous thrips Frankliniella occidentalis and Haplothrips brevitubus

et al. 2021

View full text Add to dashboard Cite

Insect metamorphosis into an adult occurs after the juvenile hormone (JH) titer decreases at the end of the juvenile stage. This generally coincides with decreased transcript levels of JH-response transcription factors Krüppel homolog 1 (Kr-h1) and broad (br), and increased transcript levels of the adult specifier E93. Thrips (Thysanoptera) develop through inactive and non-feeding stages referred to as “propupa” and “pupa”, and this type of distinctive metamorphosis is called neometaboly. To understand the mechanisms of hormonal regulation in thrips metamorphosis, we previously analyzed the transcript levels of Kr-h1 and br in two thrips species, Frankliniella occidentalis (Thripidae) and Haplothrips brevitubus (Phlaeothripidae). In both species, the transcript levels of Kr-h1 and br decreased in the “propupal” and “pupal” stages, and their transcription was upregulated by exogenous JH mimic treatment. Here we analyzed the developmental profiles of E93 in these two thrips species. Quantitative RT-PCR revealed that E93 expression started to increase at the end of the larval stage in F. occidentalis and in the “propupal” stage of H. brevitubus, as Kr-h1 and br mRNA levels decreased. Treatment with an exogenous JH mimic at the onset of metamorphosis prevented pupal-adult transition and caused repression of E93. These results indicated that E93 is involved in adult differentiation after JH titer decreases at the end of the larval stage of thrips. By comparing the expression profiles of Kr-h1, br, and E93 among insect species, we propose that the “propupal” and “pupal” stages of thrips have some similarities with the holometabolous prepupal and pupal stages, respectively.

show abstract

Section: Possible Regulatory Mechanism Of E93 Transcription In Thripssupporting

confidence: 53%

Section: Possible Regulatory Mechanism Of E93 Transcription In Thripsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of E93 in neometabolous thrips Frankliniella occidentalis and Haplothrips brevitubus

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Another endocrine organ in insects, the corpus allatum (plural: corpora allata (CA)), is also innervated with certain neurons. The CA are crucial organs for the biosynthesis and secretion of the sesquiterpenoid hormone named juvenile hormone (JH), which plays essential roles in a wide variety of aspects of insect development and physiology, including the larval‐to‐adult transition, oogenesis, epithelial morphogenesis, neuronal development, diapause, behavior, and longevity (Martín et al., 2021; Riddiford, 2020). Previous studies had suggested that neuronal inputs to the CA are essential for regulating JH biosynthesis and/or secretion, thereby regulating the biological events.…”

Section: Introductionmentioning

confidence: 99%

A population of neurons that produce hugin and express the diuretic hormone 44 receptor gene projects to the corpora allata in Drosophila melanogaster

et al. 2021

View full text Add to dashboard Cite

The corpora allata (CA) are essential endocrine organs that biosynthesize and secrete the sesquiterpenoid hormone, namely juvenile hormone (JH), to regulate a wide variety of developmental and physiological events in insects. CA are directly innervated with neurons in many insect species, implying the innervations to be important for regulating JH biosynthesis. Although this is also true for the model organism Drosophila melanogaster, neurotransmitters produced in the CA‐projecting neurons are yet to be identified. In this study on D. melanogaster, we aimed to demonstrate that a subset of neurons producing the neuropeptide hugin, the invertebrate counterpart of the vertebrate neuromedin U, directly projects to the adult CA. A synaptic vesicle marker in the hugin neurons was observed at their axon termini located on the CA, which were immunolabeled with a newly‐generated antibody to the JH biosynthesis enzyme JH acid O‐methyltransferase. We also found the CA‐projecting hugin neurons to likely express a gene encoding the specific receptor for diuretic hormone 44 (Dh44). Moreover, our data suggest that the CA‐projecting hugin neurons have synaptic connections with the upstream neurons producing Dh44. Unexpectedly, the inhibition of CA‐projecting hugin neurons did not significantly alter the expression levels of the JH‐inducible gene Krüppel‐homolog 1, which implies that the CA‐projecting neurons are not involved in JH biosynthesis but rather in other known biological processes. This is the first study to identify a specific neurotransmitter of the CA‐projecting neurons in D. melanogaster, and to anatomically characterize a neuronal pathway of the CA‐projecting neurons and their upstream neurons.

show abstract

“…Another endocrine organ in insects, the corpus allatum (plural: corpora allata (CA)), is also innervated with certain neurons. The CA are crucial organs for the biosynthesis and secretion of the sesquiterpenoid hormone named juvenile hormone (JH), which plays essential roles in a wide variety of aspects of insect development and physiology, including the larval-to-adult transition, oogenesis, epithelial morphogenesis, neuronal development, diapause, behavior, and longevity (Martín et al, 2021; Riddiford, 2020). Previous studies had suggested that neuronal inputs to the CA are essential for regulating JH biosynthesis and/or secretion, thereby regulating the biological events.…”

Section: Introductionmentioning

confidence: 99%

A population of neurons that produce hugin and express thediuretic hormone 44 receptorgene projects to the corpora allata inDrosophila melanogaster

Mizuno

Imura

Kurogi

et al. 2021

Preprint

View full text Add to dashboard Cite

The corpora allata (CA) are essential endocrine organs that biosynthesize and secrete the sesquiterpenoid hormone, namely juvenile hormone (JH), to regulate a wide variety of developmental and physiological events in insects. Previous studies had demonstrated that the CA are directly innervated with neurons in many insect species, implying the innervations to be important for regulating JH biosynthesis in response to internal physiology and external environments. While this is also true for the model organism, Drosophila melanogaster, which neurotransmitters are produced in the CA-projecting neurons are yet to be clarified. In this study on D. melanogaster, we aimed to demonstrate that a subset of neurons producing the neuropeptide hugin, the invertebrate counterpart of the vertebrate neuromedin U, directly projects to the adult CA. A synaptic vesicle marker in the hugin neurons was observed at their axon termini located on the CA, which were immunolabeled with a newly-generated antibody to the JH biosynthesis enzyme JH acid O-methyltransferase (JHAMT). We also found the CA-projecting hugin neurons to likely express a gene encoding the specific receptor for diuretic hormone 44 (Dh44). Moreover, our data suggested that the CA-projecting hugin neurons have synaptic connections with the upstream neurons producing Dh44. To the best of our knowledge, this is the first study to identify a specific neurotransmitter of the CA-projecting neurons in D. melanogaster, and to anatomically characterize a neuronal pathway of the CA-projecting neurons and their upstream neurons.

show abstract

How stage identity is established in insects: the role of the Metamorphic Gene Network

Cited by 40 publications

References 71 publications

Characterization of E93 in neometabolous thrips Frankliniella occidentalis and Haplothrips brevitubus

Characterization of E93 in neometabolous thrips Frankliniella occidentalis and Haplothrips brevitubus

A population of neurons that produce hugin and express the diuretic hormone 44 receptor gene projects to the corpora allata in Drosophila melanogaster

A population of neurons that produce hugin and express thediuretic hormone 44 receptorgene projects to the corpora allata inDrosophila melanogaster

Contact Info

Product

Resources

About