Submitted to: University of Missouri Life Sciences Week
Publication Type: Abstract only
Publication Acceptance Date: 3/5/2004
Publication Date: 4/8/2004
Citation: Habibi, J., Shelby, K., Puttler, B. 2004. Ultrastructure of the teratocytes of the endoparasitic braconid wasp microctonus aethiopoides [abstract]. University of Missouri Life Sciences Week. Available from: http://lsrdb.missouri.edu/cgi-bin/searchsortlsrdb.cgi. Interpretive Summary:
Technical Abstract: The braconid Microctonus aethiopoides is a koinobiont endoparasitoid of alfalfa weevil adults. After oviposition and subsequent egg maturation large trophic cells called teratocytes dissociate from the serosal membrane and are released into the host hemocoel where over a period of weeks they grow to enormous size--visible to the naked eye. Teratocytes accumulate host hemocoelic metabolites which are believed to be consumed by the parasitoid larva. We have undertaken ultrastructural and fluorescent studies of these gargantuan and complex cells utilizing TEM and confocal microscopy. Parasitized adults were dissected in medium, the teratocytes were collected, fixed, embedded and cut into one micrometer sections. Sections were stained with various specific fluorescent dyes for plasma membrane, Golgi, nuclei, lysosomes, mitochondria and endoplasmic reticulum. Analysis of fluorescent images showed that these cells do not have condensed nuclei. ER was abundant around the nuclear envelope. Lysosomes were positioned around the periphery of the nucleus and Golgi apparatus was significantly enlarged, being located around the nuclear envelope. TEM reveals the presence of dense, long microvilli over the entire plasma membrane, and closely associated mitochondria and rough endoplasmic reticulum, indicating both high levels of nutrient uptake, and protein synthesis.