TY - JOUR
T1 - Pygidial glands of Harpalus pensylvanicus (Coleoptera: Carabidae) contain resilin-rich structures
AU - Rork, Adam M.
AU - Mikó, István
AU - Renner, Tanya
N1 - Funding Information:
We thank Sulav Paudel, Asifa Hameed, Po-An Lin, Ching-Wen Tan, and Maria Perezsandi for thoughtful discussion and assistance with dissections. We also thank Andy Deans for constructive feedback, as well as Jonah Ulmer, Chloe Drummond, and Kylie Bocklund for thoughtful discussions on staining. Finally, we thank Missy Hazen and John Cantolina for their help with CLSM and Olympus BX61 imaging (Penn State Microscopy and Cytometry Facility - University Park, PA). This work was supported by the National Science Foundation (DEB 1556931/1762760 to Tanya Renner).
Publisher Copyright:
© 2019 The Authors
PY - 2019/3
Y1 - 2019/3
N2 - The pygidial gland system is a key innovation in adephagan beetles, producing, storing, and spraying defensive chemical compounds. As the source of defensive chemical production and storage, the pygidial gland system experiences severe chemical stress which challenges the integrity of the entire gland system. Here, we utilize autofluorescence-based confocal laser scanning microscopy to examine the morphology of pygidial gland secretory lobes and collecting ductules in a common Pennsylvanian harpaline species, Harpalus pensylvanicus. The glandular units are composed of type-III exocrine cells which empty into resilin-rich ductules, which themselves lead into a larger resilin-rich collecting duct, and ultimately the pygidial reservoir pump. We also utilize histological staining with toluidine blue and brightfield imaging to provide additional support for the presence of resilin in the collecting duct, as toluidine blue has been shown to stain resilin without metachromasia. We hypothesize that the high resilin content of the collecting ducts might be a widespread key evolutionary adaptation to prevent damage caused by physical and chemical stress generated in pump-containing insect exocrine gland systems.
AB - The pygidial gland system is a key innovation in adephagan beetles, producing, storing, and spraying defensive chemical compounds. As the source of defensive chemical production and storage, the pygidial gland system experiences severe chemical stress which challenges the integrity of the entire gland system. Here, we utilize autofluorescence-based confocal laser scanning microscopy to examine the morphology of pygidial gland secretory lobes and collecting ductules in a common Pennsylvanian harpaline species, Harpalus pensylvanicus. The glandular units are composed of type-III exocrine cells which empty into resilin-rich ductules, which themselves lead into a larger resilin-rich collecting duct, and ultimately the pygidial reservoir pump. We also utilize histological staining with toluidine blue and brightfield imaging to provide additional support for the presence of resilin in the collecting duct, as toluidine blue has been shown to stain resilin without metachromasia. We hypothesize that the high resilin content of the collecting ducts might be a widespread key evolutionary adaptation to prevent damage caused by physical and chemical stress generated in pump-containing insect exocrine gland systems.
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U2 - 10.1016/j.asd.2018.12.004
DO - 10.1016/j.asd.2018.12.004
M3 - Article
C2 - 30703537
AN - SCOPUS:85061692920
SN - 1467-8039
VL - 49
SP - 19
EP - 25
JO - Arthropod Structure and Development
JF - Arthropod Structure and Development
ER -