Disappearance of fat body proteins during soldier differentiation in the neotropical termite Heterotermes tenuis (Isoptera: Rhinotermitidae)

Termites are social insects with well-defined castes: workers, soldiers and reproductives. The soldier is a terminal stage and originates from either larvae or workers after two molting processes that include an intermediate presoldier instar. The present study followed the occurrence and morphologi...

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Detalles Bibliográficos
Autores: Laranjo, Lara Teixeira [UNESP], Costa-Leonardo, Ana Maria [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/128676
Acceso en línea:http://link.springer.com/article/10.1007%2Fs00435-014-0241-8
http://hdl.handle.net/11449/128676
Access Level:acceso abierto
Palabra clave:Adipocytes
Urocytes
Caste differentiation
Subterranean termite
Descripción
Sumario:Termites are social insects with well-defined castes: workers, soldiers and reproductives. The soldier is a terminal stage and originates from either larvae or workers after two molting processes that include an intermediate presoldier instar. The present study followed the occurrence and morphological changes of the fat body during the soldier ontogeny in the neotropical termite Heterotermes tenuis. Workers and soldiers collected in the field and presoldiers obtained in laboratory were fixed in FAA fixative and embedded in resin for light microscopy. The histological sections were submitted to histochemical tests for protein and urate detection. The fat body in all the individuals showed only two cellular types: adipocytes and urocytes. The adipocytes of presoldiers displayed some lipid droplets, and a large amount of acidophilic granules interpreted as proteins because they were strongly stained by xylidine Ponceau. In soldiers, the fat body was deprived from proteins and showed a higher quantity of urocytes with many urate spherocrystals compared with those present in workers and presoldiers. The results were consistent with metamorphosis process and with the possibility of presoldiers being at the beginning of molting stage. The occurrence of many protein granules suggests uptake and consumption of protein storage during the whole development of the presoldiers into soldiers. The dynamic transformations of the fat body enable the individuals of different phenotypes to accomplish their role in the termite colony.