The mushroom bodies of crabs: the hemiellipsoid body.

AVISHAG SHKEDY; JULIETA SZTARKER; FRANCISCO J. MAZA; FERNANDO LOCATELLI; JOSÉ CLEMENTE; ALEJANDRO DELORENZI

Mar del Plata

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

Sociedad Argentina de Investigación en Neurociencias

The hemiellipsoid body (HB) is a neuropil located in the lateral protocerebrum of crustaceans. HB is a multi-sensorial integration center where some memory and learning data processing are proposed to take place. Two related structures, mushroom bodies(MB) in insects and pallium in vertebrates appear to share a common origin (Tomer et al 2010). MB is a higher order integration center involved in cross-sensory integration and memory formation. HB has been scarcely studied in true crabs, Brachyura crustaceans, like Neohelice granulata, where several memory processes have been profusely studied. Golgi staining show that, like the MB in insects, the HB globulli cells project to a tract that is subdivided into lobes and claw cells are present (Strausfeld 2015). This neuropil lacks of calyces, a common feature in aquatic arthropods. We used immunohistochemistry methods to explore the expression patterns of neuronal markers previously described in both HB and MB. To explore their function, in vivo assays were made by applying Calcium Green (see poster Maza et al.). Results reveal the expected patterns for allatostatine,synapsin and CAMKII (Harzsch et al. 2012). CAMKII and Calcium green stain facilitate the detection of the globulli cells cluster and allow visualization of its tracts leading to the HB. These findings match the morphological patterns described for the HB and MB in other arthropods and further support the common origin of both structures.