Prothoracicotropic hormone (PTTH) controls the synthesis of ecdysteroids (molting hormones) by the insect prothoracic gland and thereby plays a critical role in insect growth, molting, and metamorphosis. PTTH has been purified, and cDNA clones obtained, from only one insect, the silkmoth Bombyx mon. Recently, a partial amino acid sequence was obtained for-a putative PTTH from the tobacco hornworm, Manduca sexta, and the data suggested an unexpected homology to a vertebrate retinoid binding protein rather than to the Bombyx PTTH. In this study, a monoclonal antibody against the Bombyx PTTH was added to in vitro assays that assess the ability of partially purified Manduca PTTH to stimulate prothoracic gland ecdysteroid and protein synthesis. The results indicate that Bombyx and Manduca PTTHs are indeed members of the same protein family that have likely diverged in the PTTH receptor-binding region.

Download full-text PDF

Source
http://dx.doi.org/10.1006/gcen.1996.0066DOI Listing

Publication Analysis

Top Keywords

bombyx manduca
8
prothoracic gland
8
bombyx ptth
8
ptth
7
bombyx
5
manduca prothoracicotropic
4
prothoracicotropic hormones
4
hormones immunologic
4
immunologic test
4
test relatedness
4

Similar Publications

The prophenoloxidase (PPO) activation and Toll antimicrobial peptide synthesis pathways are two critical immune responses in the insect immune system. The activation of these pathways is mediated by the cascade of serine proteases, which is negatively regulated by serpins. In this study, we identified a typical serpin, BmSerpin-4, in silkworms, whose expression was dramatically up-regulated in the fat body and hemocytes after bacterial infections.

View Article and Find Full Text PDF

Prostaglandins (PGs) mediates the immune response of insects to multiple stimuli. Mammalian cyclooxygenase (COXs) is a key enzyme in the synthesis of PGs, and peroxinectin (Pxt) may have similar functions in some sequenced insect genomes. As a representative of Lepidoptera, the silkworm also contains PGs, but its synthetic pathway is not clear.

View Article and Find Full Text PDF

Functional annotation of insecta transcriptomes: A cautionary tale from Lepidoptera.

Insect Biochem Mol Biol

February 2024

Department of Biology, Tufts University, 200 Boston Ave, Medford, MA, 02155, USA. Electronic address:

Functional annotation is a critical step in the analysis of genomic data, as it provides insight into the function of individual genes and the pathways in which they participate. Currently, there is no consensus on the best computational approach for assigning functional annotation. This study compares three functional annotation methods (BLAST, eggNOG-Mapper, and InterProScan) in their ability to assign Gene Ontology terms in two species of Insecta with differing levels of annotation, Bombyx mori and Manduca sexta.

View Article and Find Full Text PDF

In this study, cocoons and degummed silk samples of Bombyx mori and twenty Saturniidae species of the genera Actias, Attacus, Argema, Antheraea, Caligula, Callosamia, Cricula, Epiphora, Hyalophora, Loepa, Samia and Saturnia are studied to gain an insight into their morphology, chemical composition and physical structure. For this purpose, silk samples are characterized by optical microscopy and FTIR spectroscopy in attenuated total reflection mode (ATR-FTIR spectroscopy). Furthermore, degummed silk samples are analyzed for their amino acid (AA) composition by GC-FID.

View Article and Find Full Text PDF

Insect growth is interrupted by molts, during which the insect develops a new exoskeleton. The exoskeleton confers protection and undergoes shedding between each developmental stage through an evolutionarily conserved and ordered sequence of behaviors, collectively referred to as ecdysis. Ecdysis is triggered by Ecdysis triggering hormone (ETH) synthesized and secreted from peripheral Inka cells on the tracheal surface and plays a vital role in the orchestration of ecdysis in insects and possibly in other arthropod species.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!