The mushroom bodies of crabs: the hemiellipsoid body.

AVISAHG SHKEDY; JULIETA SZTARKER; FRANCISCO JAVIER MAZA; FERNANDO LOCATELLI; A. DELORENZI

Mar del Plata

Congreso; XXX Reunión Anual de la Sociedad Argentina de Investigación en Neurociencias,; 2015

SAN

The hemiellipsoid body (HB) is a neuropil located in the lateralprotocerebrum of crustaceans. HB is a multi-sensorial integration center wheresome memory and learning data processing are proposed to take place. Tworelated structures, mushroom bodies (MB) in insects and pallium in vertebratesappear to share a common origin (Tomer et al 2010). MB is a higher orderintegration center involved in cross-sensory integration and memory formation.HB has been scarcely studied in true crabs, Brachyura crustaceans, like Neohelice granulata, where severalmemory processes have been profusely studied. Golgi staining show that, likethe MB in insects, the HB globulli cells project to a tract that is subdividedinto lobes and claw cells are present (Strausfeld 2015). This neuropil lacks ofcalyces, a common feature in aquatic arthropods. We used immunohistochemistrymethods to explore the expression patterns of neuronal markers previouslydescribed in both HB and MB. To explore their function, in vivo assays were made by applying Calcium Green (see poster Mazaet al.). Results reveal the expected patterns for allatostatine, synapsin andCAMKII (Harzsch et al. 2012). CAMKII and Calcium green stain facilitate the detectionof the globulli cells cluster and allow visualization of its tracts leading tothe HB. These findings match the morphological patterns described for the HBand MB in other arthropods and further support the common origin of bothstructures.