embryonic/larval mushroom body [FBbt_00011929]

embryonic/larval mushroom body

ID: FBbt_00011929

Mushroom body (MB) of the larva. It only has two lobes, medial and vertical, in contrast to the adult MB, which has five lobes (Lee et al., 1999). Both lobes are composed of gamma neurons, which are the only Kenyon cells (KCs) present in the newly hatched first instar (Kunz et al., 2012). MB neuroblasts continue to produce new KCs throughout the larval stages (Lee et al., 1999). These new KCs form layers in the larval MB peduncle and lobes, with four distinguishable layers present in the third instar (Kurusu et al., 2002). Three types of KCs can be identified in these layers: embryonic-born gamma type (surface layer), larval-born gamma type (outer and inner layers) and larval-born alpha'/beta' type (core layer) neurons (Kurusu et al., 2002). During the pupal stage, alpha/beta KCs are produced and the larval MB is remodeled into the adult MB (Lee et al., 1999).

The four layers in the pedunculus and lobes were identified by staining with a FasII antibody. The surface layer is partially FasII-negative, the outer and inner layers are FasII-positive and the core is FasII-negative (Selcho et al., 2009; Kurusu et al., 2002).